I hate SWR.

[The Golden Boy]

Last night I had a show and my SWR SM-900 went into thermal shutdown. Again.

The SM-900 was SWR's "flagship" model. It's very powerful, it's got plenty of headroom, a very controllable EQ, it's light, and it sounds awesome. It's a phenomenally great sounding amp. But it has a habit of "blowing up." It's not like I'm pushing it really hard (bass at 12:00, pre around 11:00, master vol at 9:00) and it's well within it's impedance range (an SWR 2x15 cab in bridged mode). I had issues when I first got the amp, little QC things like mystery screws rattling around in the chassis, improperly wired DI, bad fuse well, bad LED/cold solder joint... So I figured it was just another of it's quirks that needed to be fixed up. I had it in to the authorized tech's shop far too many times- what it came down to (for the overheating problem) is that the air isn't flowing like it should. It's mounted in an SKB rack, as it's designed to be used in a rack, and it would always overheat- sometimes blowing output fuses, sometimes just going into thermal shutdown. In any case, it was a $1200+ amp, and it was completely and totally unreliable.

The amp is designed to passively draw air in the back, force it through the heat sinks towards a grill on the side of the amp. That design doesn't take into account of being used in the confines of a rack case. The wall of the rack is less than an inch from the wall of the amp, and the rack entirely encloses the amp. What that means is that the hot air that is removed from the amp chassis gets recirculated into the amp because most of that hot air stays within the rack. Also keep in mind nothing actively forces or pulls air in or out of the amp chassis- there's a fan in the center of the amp that blows it TOWARDS the grill. As the hot air does go out the heat sinks- because the rack wall is so close there's resistance to the air exiting the chassis and a lot of the hot air doesn't make it out of the chassis and keeps getting heated again.

The tech suggested that I get a fan to either blow air into or remove air from the rack. So I got a fan from Radio Shack and mounted it onto the upper rack rail in the back. It removes the hot air that builds up in the rack. It's done well in the past 5 years or so. The amp has never overheated, blew a fuse or even run hot since then. I used the amp a lot, it was used several times a week for rehearsal, gigged every few weeks until last year. For the past year it sees use about once a week and gigged about once a month.

Last night in the middle of the set, probably an hour and a half in- it just stopped in the middle of a song. I still had power to my power supply, but the amp LEDs were off... As soon as I touched the rack handles I knew what had happened again. It was my first show with this band, and not only was I embarrassed, but absolutely livid that it would happen again. As awesome as this amp could be, I ****ing hate it.

The SWR SM-900. Notice the covered SWR logo- because of their 'awesome' "customer service" I refuse to leave those logos visible and do any sort of advertising for them:

http://images.lilypix.com/albums/userpics/10038/normal_rackface.jpg

The "guts" of the amp- the long black rectangles are the heat sinks- the fan is just to the right of the heat sinks. The air should be drawn from the vent in the back (at the top of the pic) and then through the heat sinks towards the vent off to the left of the heat sinks. Yeah- That'll work.

http://images.lilypix.com/albums/userpics/10038/normal_SWRguts.jpg

And here's the back of the rack, showing the fan I installed into the rack- it's noisy but until yesterday, it did a wonderful job of removing hot air from the rack and keeping the amp cool. Notice the packages of fuses taped to the wall of the rack- just in case.

http://images.lilypix.com/albums/userpics/10038/normal_rackback.jpg

[The Golden Boy]

I should also note the EQ in the first picture is pretty close to how I was running it last night- I had both parametrics engaged and with a little less low end and a the low mids pulled back because I was using the Thunderbird- a bassy, low middy instrument.

[Fuchsaudio]

Looks to me like a fan could be added on the rear of the amp chassis. An opening should be made in the rack side (add a fan grille) so the amp can blow it's heat out the side of the rack. I had a PS-400 for many years, and as long as I kept it cool, it was happy. One night I used one channel to run the bands monitor system, when the power amp we used had died, and it worked like a champ. Decent amp, but like to breathe.

[John Phillips]

Stops Working Regularly.

Nice sounding amps, when they work. I wouldn't advise anyone to buy one.

Personally I would have ditched it years ago, no matter how good it sounded. I don't like gear that has to be babied in order to run reliably. Designing a rack unit with its main cooling outlet on the side is just asking for trouble.

[The Golden Boy]

A Fender PS-400? A friend had a PS-300 that he was going to fix up for me, until he figured out that it was the 50lb OT that was trashed. I've heard they're supposed to be some really cool amps after tweaking the EQ. The 300 was heavy... I think it ran a 6v6 as a rectifier tube...

I've thought about cutting a hole in the rack wall, or at least drilling holes into it. I just don't want to compromise the "integrity" of the protection of the case itself. Now that I think about it, it sounds pretty stupid. When do I ever leave my stuff in the rain? :messedup

Do you think it'd make more sense to pull air through rather than forcing air in?

[John Phillips]

Do you think it'd make more sense to pull air through rather than forcing air in?It doesn't make any difference if there are no other outlets - if you force more air in through the back as Andy say, it has to go somewhere, and out through the heatsink should be the only path, so it will increase cooling. It may actually help to deliberately block the gap around the end of the heatsink (and along the top) to make sure hot air cannot bypass the exit vent and return round to the inlet end. In fact, is there room between the end of the heatsink and the side of the case to get another fan in there, so you could do both? It does sound like forced cooling is the only solution for these amps.

I would avoid cutting a hole in the flightcase, it shouldn't be necessary. You can make cooling air go a very complex path and still work OK if it's well thought out - check out a Peavey Classic 50 :).

[Witek]

Go to any computer geek store and invest yourself in a water cooling system. That should cool things up a bit.

Or you know, go buy another amp :P

[The Golden Boy]

I haven't gotten around to looking at it yet- I did let the cooling fan run for the rest of the show, and of course the amp fired right back up, so it was just a matter of going into thermal protect shutdown.

My guess is that the fan inside the amp failed. I've run it for much longer running 4 ohms in bridged mode as well as running 4 ohm cabs on each side. It hasn't run this hot since installing the external fan.
It doesn't make any difference if there are no other outlets - if you force more air in through the back as Andy say, it has to go somewhere, and out through the heatsink should be the only path, so it will increase cooling. It may actually help to deliberately block the gap around the end of the heatsink (and along the top) to make sure hot air cannot bypass the exit vent and return round to the inlet end. In fact, is there room between the end of the heatsink and the side of the case to get another fan in there, so you could do both? It does sound like forced cooling is the only solution for these amps.

I would avoid cutting a hole in the flightcase, it shouldn't be necessary. You can make cooling air go a very complex path and still work OK if it's well thought out - check out a Peavey Classic 50 :).

If you'll notice in the middle pic the tech put plastic pieces between the fan and the heatsink to attempt to make sure the air is getting into the heatsink.

I'll check to see the actual room between the heatsink and the chassis wall. I'm not adverse to adding yet another fan, but I'm not drilling holes in the amp- anything beyond the price of a fan isn't worth it. I've said for years "when I get the money..." that this amp is getting replaced- this might just be the kick in the ass I need.

[Tone_Terrific]

Too much stuff in the rack, unfortunate air design-
-remove it from the rack.
-build a nice little wooden case for it with side air exit...problem should be gone

[The Golden Boy]

The power supply, on top, takes up less than half the space of the amp, the tuner, directly above the amp, is about a quarter of the size of the amp (from front to back).

Any radiant heat from the top lid of the amp has air to circulate. Although I'm not any kind of authority on using racks, I've seen people running Mesa Boogie Bass 400+ amps in racks that fit the amp (same amount of rack spaces as the amp) with no ill effects. In that case, you're talking about an amp running like 12 6L6s...

[John Phillips]

Yes, but tubes don't suffer from thermal runaway like transistors do. You can overheat a tube amp, but it won't shut itself down by overloading the trip or blowing the fuse like that - in fact, it could be worse because nothing will happen until some component or other simply fails with the heat. I assume that the Mesa is designed to be cooled purely from the back, though (too long since I saw one, I can't remember).

It comes down to poor design with the SWR. No rack unit should be designed with a critical cooling vent anywhere other than on the back or front, because it must be assumed that it will be mounted in a rack! I suspect the cooling is inadequate for the power that amp dissipates anyway - the whole thing looks like some components, heatsinks and a fan just thrown in a case, not properly designed with an effective ventilation path.

[ChickenLover]

That's a bad design regarding the fan...you're right that the fan should pull air over the heat sinks and out of the chassis. The fan should be at the 'exit'...just like almost every other exhaust fan you'll see. Had they mounted the fan on the side of the chassis (at the other end of the heat sinks) and designed it such that the air flow went over the heat sinks it would have been better.

It surprises me that these amp makers get so 'cute' with the cooling. Even when using amps from different mfrs. you have to be careful because one might front-to-back, another back-to-front,, and another front-to-side, or any combination you can think of.

[Stormin]

SWR's are NOTORIOUS for thermal shutdown problems. Some models suffer more than others from this. You can do a search over at www.TalkBass.com (http://www.TalkBass.com) to get some ideas from others on how to solve the cooling issues.

That said, I have a Bass 350 that I love. It's one of the worse designs for the thermal shutdown problem. My solution - just don't rack it. I simplified my rig to just the head and a small non-rack tuner. I know it sucks to accept this, but you can either work around the amp as it is or trade it in on an Eden WT-800.

YMMV,

Stormin!

[m3g]

Like many have said before, you gotta let that sucker breathe. I used to use an SM900 with my former band and never had any problems as long as the head was not in a rack.

[BJF]

Hi,

The fan mounted at the back of your rack won't do much if any difference as it would cool maybe what's on top.

Ah, isn't that sad seeing economics department at work?

Now, that amp shuts down is better than that it blows up. Likely the amp was designed to run at less than full power and with good ventilation.

Is this a Mos Fet head or bipolar?
Might be a hrd question to answer unless your a tech, while it also might say in the productfile.

Bipolar transistors can go into thermal rundown andthis is something you calculate on- OK so maybe the whitefrock guys hide behind a table when flipping the power switch to a 300W monster- something you'd need when competing volumewise with 75W distorted guitar amps but still a monster.

Likely you have a secure system that saves the precious power trannies. It is common parctice to use the least amount of heatsink and a fan to decrease thermal resisttans.

Ok so if it is a bipolar you might ask your tech to change the trannies for MJ150023/MJE15024 to increase distance to thermal shutdown.

Solid state is solid aslong as you don't do design on the brink of maximum.

For bass, you'd actually need 'clean' power and if you'd want that to sound like bass from the 70's you may just overdrive it use flatwouonds and wear a moustache.

Not that wearing a moustache approaches any wimp status considering LEMMY.........


My advice is to have a qualified tech have a look at your unit to see the realms of what can be done and considere someting higher powered.

Yikes to my memory when my bassist got an Ampeg 400 transistor power it went so clear while also to the point I'd feel exhausted as the power just sucked all air outof my lungs while it still was clean and stable.

I would recommend you check out the Ampeg's but for the sake of your guitarist's and fellow mucisians be modest on volume.
If you want to get a headace on a constant status blast the EBS, which is just as gruesome but more hightech than the Ampeg.

Yes I have worked their servicedepartment and they hold high power. I have also repaired quite a few SWR's

On the argument solid state versus tubes you may figure why they have tubes in missile silos
but shere power to cut basstracks............

Carry on gentlemen
BJ


Affiliations
www.bjfelectronics.com (http://www.bjfelectronics.com)
www.mpamp.com (http://www.mpamp.com)

[Gas-man]

Quick suggestion for a cheap, reliable, very good sounding bass head is the Behringer 300 watter.

I played one on Saturday through a 8x8 cab and it sounded great.

The heads are like 200 bucks.

[BJF]

Hi,

As a service technician I' d be tempted to say cheap is not reliable. At anythingabove cheap somethings are reliable others not and it comes down to what the economoics department has to say about what parts to use and the application- sometimes just higher wattage is just the key.

Yes I saw the videos from the Behringer plant and would be tempted to say more power to Udo, but at the same trime this is the same kind of gear that was offered in the 70's but adapted to 90's
As a musician I have seen things sounding good only to die the next moment- fine except you have two more hours of the show.

Fine Raw Power to the people and get the funk out!!!
Affiliations
BJF Electronics
Sweden
www.bjfelectronics.com
www.mpamp.com

[Gas-man]

Hi,

As a service technician I' d be tempted to say cheap is not reliable. At anythingabove cheap somethings are reliable others not and it comes down to what the economoics department has to say about what parts to use and the application- sometimes just higher wattage is just the key.

Yes I saw the videos from the Behringer plant and would be tempted to say more power to Udo, but at the same trime this is the same kind of gear that was offered in the 70's but adapted to 90's
As a musician I have seen things sounding good only to die the next moment- fine except you have two more hours of the show.

Fine Raw Power to the people and get the funk out!!!
Affiliations
BJF Electronics
Sweden
www.bjfelectronics.com (http://www.bjfelectronics.com)
www.mpamp.com (http://www.mpamp.com)

True enough.

But we didn't have China in the 1970's.

My experience with Chinese musical equipment in the lat 5 years has been excellent.

The prices you can get high quality gear for is just nuts these days.

I could never buy a cool fuzz/octave pedal for 30 bucks when I was a kid. Boss pedals cost $100 in 1984--which is the equivalent of at least $150 in today's dollars. Now every snot-nosed punk can score a ton of very usuable stuff for next to nothing and enjoy it.

[John Phillips]

Quick suggestion for a cheap, reliable, very good sounding bass head is the Behringer 300 watter.
Reliable? Those things break all the time. Total junk. I couldn't tell you what they sound like since all the ones I've come across have been dead...

All Behringer gear is crap. I won't even work on it... I don't want to be blamed when it breaks again.

[jay42]

Could try a 6 space rack with two open slots above it. There should be 1 space fan modules to keep air moving by it or at it...doesn't mean there are, but there should be.

[aeolian]

The bass player in my band shelved his SWR and got an Eden. He loves the sound of the SWR for small gigs, but it was shutting down constantly. Last year at a big festival was the last straw for him.

Many years ago when I worked at Dolby, a guy there had a RedHead go out on him so we opened it up. Nobody could believe how chintzy the innards of that amp were. Great sound, but really marginal excecution. Everyone starting thinking up ways to improve it. More ps storage, better output devices (as recommended above), better thermal management.

The pics above are amazing. With all that has been learned in thermal management of 2U PA amps in the last several years, you'd think it would be obvious.

[BJF]

True enough.

But we didn't have China in the 1970's.

My experience with Chinese musical equipment in the lat 5 years has been excellent.

The prices you can get high quality gear for is just nuts these days.

I could never buy a cool fuzz/octave pedal for 30 bucks when I was a kid. Boss pedals cost $100 in 1984--which is the equivalent of at least $150 in today's dollars. Now every snot-nosed punk can score a ton of very usuable stuff for next to nothing and enjoy it.

Hi

Yes we did.

Punk never dies

Have fun
BJ

[Gas-man]

Hi

Yes we did.

Punk never dies

Have fun
BJ


Perhaps in Sweden.

:p

[Gas-man]

Reliable? Those things break all the time. Total junk. I couldn't tell you what they sound like since all the ones I've come across have been dead...

All Behringer gear is crap. I won't even work on it... I don't want to be blamed when it breaks again.


Hehehe...must be a Scottish thang.

I'm sure it's hard to get the haggis out of any amp.

:BEER

[BJF]

Perhaps in Sweden.

:p

Hi,
True

Not sure about anywhareelse back then though.

HAve great fun and punk rules :BOUNCE

BJ

Affiliations
www.mpamp.com
bjfelectronics.com

[conundrum]

Perhaps in Sweden.

:p

Punk Refused to die in Sweden.



See what I did there.:dude

[Gas-man]

What is this "punk" you speak of?

Perhaps if you sent me a Honey Bee I could try out this exotic new music and report back?

[macmax77]

What about Hartke?Or Mesa?

[musicofanatic5]

While I often find myself in disagreement with this fella's declamitory statements, I am right with him when he says, "All Behringer gear is crap." I have a friend who is sound reinforcement department manager at a GC who's mantra is "Friends don't let friends buy Behringer".
There is nothing I hate worse than showing up for a gig and the backline bass amp is SWR or Eden. It seems to have some sort of eq curve built in that favors the snarkey boinka-boinka modern bassist sound. I hate that.
________
hash (http://trichomes.org/hashish/full-melt-hash)

[jay42]

re:SWR, Eden...get a QSC PLX series power amp and find a tube preamp you like. Tons more power for reasonable bucks. Rider friendly.

[SvenHock]

I had one of those SM-900's a few years ago. That thing would shut down on me racked or unracked. One of the best sounding bass amps I ever had but was worthless because of the reliability issue.

[drbob1]

Isn't the SWR preamp basically the same as the Groove Tubes one? If that's the sound you're looking for, I agree: buy the preamp and run it thru any of the reasonably cheap, bulletproof power amps that are out there. Carry a Powerblock as a spare (makes a killer little bass amp, esp at 150w into 8 ohms).

[Fuchsaudio]

Bob: The SWR folks made the Groove Tubes preamps. You are right. Adding that preamp to a good power amp (Crown, QSC, etc.) would be a decent combination. Amazingly, despite the QC issues, SWR eventually got bought by Fender, so go figure. Their little combos are made in India or Malaysia, just horribly made stuff. Makes me happy I'm not in the service mainstream anymore. I guess I was lucky my SWR-400 lasted almost 20 years with little more than a tube replacement and making sure it could breathe.

[zekmoe]

I'm no fan of the SWR electronics. I think the cabs are good though. But their head gear SOUNDS terrible IMHO. Thin, and without overtones. Equivilantly priced Ampeg or Thunderfunk gear kills it.

[Denyle_Guitars]

Looks like a lot of SWR haters here. It's unfortunate but it sounds like it's somewhat justified. It's too bad some of their larger amps have issues but I wouldn't own one for the simple reason that I'd rather have a SVT or a Thunderfunk or Eden or...you get the idea. OTOH, If it wasn't for Steve Rabe, I doubt we'd have the amp choices we have now.

I do have an original redhead combo that sounds and works great and I've never had a single issue with the amp.
It's also worth mentioning that the original baby blue combo is one of the nicest sounding small bass amps I've ever heard.

[The Golden Boy]

So this evening after rehearsal (bass player for this project used one of my Seymour heads), I had a chance to open up the amp. Yeah. Well, the internal fan is working, but... A cap broke off of the right side of the power section. Me, not being an electronics 'jeanious' have no idea what was actually going on with the amp. When I tested it in stereo mode, the left channel worked, but the right didn't. I was running a 4 ohm load in bridged mode- so the amp was "seeing" 2 ohms- perfectly acceptable and within the amp's recommended impedance range. However, half the power section wasn't working- so the amp was working harder than if it were just pushing a 4 ohm load per side.

It shouldn't be a big fix, but still...

[The Golden Boy]

It comes down to poor design with the SWR. No rack unit should be designed with a critical cooling vent anywhere other than on the back or front, because it must be assumed that it will be mounted in a rack! I suspect the cooling is inadequate for the power that amp dissipates anyway - the whole thing looks like some components, heatsinks and a fan just thrown in a case, not properly designed with an effective ventilation path.
That's a bad design regarding the fan...you're right that the fan should pull air over the heat sinks and out of the chassis. The fan should be at the 'exit'...just like almost every other exhaust fan you'll see. Had they mounted the fan on the side of the chassis (at the other end of the heat sinks) and designed it such that the air flow went over the heat sinks it would have been better.

It surprises me that these amp makers get so 'cute' with the cooling. Even when using amps from different mfrs. you have to be careful because one might front-to-back, another back-to-front,, and another front-to-side, or any combination you can think of.
SWR's are NOTORIOUS for thermal shutdown problems. Some models suffer more than others from this. You can do a search over at www.TalkBass.com (http://www.TalkBass.com) to get some ideas from others on how to solve the cooling issues.

The bass player in my band shelved his SWR and got an Eden. He loves the sound of the SWR for small gigs, but it was shutting down constantly. Last year at a big festival was the last straw for him.

Many years ago when I worked at Dolby, a guy there had a RedHead go out on him so we opened it up. Nobody could believe how chintzy the innards of that amp were. Great sound, but really marginal excecution. Everyone starting thinking up ways to improve it. More ps storage, better output devices (as recommended above), better thermal management.

The pics above are amazing. With all that has been learned in thermal management of 2U PA amps in the last several years, you'd think it would be obvious.
I had one of those SM-900's a few years ago. That thing would shut down on me racked or unracked. One of the best sounding bass amps I ever had but was worthless because of the reliability issue.
Looks like a lot of SWR haters here.
There are a lot of people with similar bad experiences with SWR gear. What's strange to me, is that when I was looking into buying a new amp (and even after I had had problems with the 2 SWR heads I had) I had only heard of positive things about SWR stuff. I'd owned 2 SWR cabs before and I was more than pleased with them, I've still got them and think the world of them. But everyone that I knew that used or had used SWR gear had nothing but good things to say. I did a lot of looking into things before I bought my first SWR head.

A few years afterwards, when I found TalkBass, when I mentioned my problems, I got piled on like I had no idea what I was doing, how the amp was being connected, what cables I was using, how I was EQing the amp, how much volume I was pushing... I've got a little bit of experience in running SS bass amps, and had never "blown" an amp before the SWR amps. As I understand the GK amps are pretty fragile about impedance mismatch and being pushed too hard (as they're passively cooled) and the only problems I had with my two Seymour Duncan amps were age related (a prior owner had done some serious "modification" to one and it was "fragile" in the physical sense, the other one was starting to get "saggy") and one instance of a piece of clothing getting sucked into the fan and blowing the fuse...

Since posting about my problems I started seeing more and more issues about this- from people I know, people on online forums and the Harmony Central reviews. (man, it's funny seeing my review- it's frickin' word for word my initial post..."the two flagship model SWR amplifiers I have owned (Bass 750 and SM-900) have not only been duds, but have been the most unreliable excuses for bass amplification I have experienced." There's a few bad reviews in there, but prior to me getting the amp, it looks like there were 2 glowing reviews)

[The Golden Boy]

Yes, but tubes don't suffer from thermal runaway like transistors do. You can overheat a tube amp, but it won't shut itself down by overloading the trip or blowing the fuse like that - in fact, it could be worse because nothing will happen until some component or other simply fails with the heat. I assume that the Mesa is designed to be cooled purely from the back, though (too long since I saw one, I can't remember).

Hey John,

The Mesa Bass 400+ has a fan on the side that blows onto the amp- the cover is a vented steel cover with an open back. The cover, more or less provides protection for the tubes but allows for air flow. I should have had pictures when I had that one for "tryouts" a few months ago.


Hi,

The fan mounted at the back of your rack won't do much if any difference as it would cool maybe what's on top.

Now, that amp shuts down is better than that it blows up. Likely the amp was designed to run at less than full power and with good ventilation.

Solid state is solid aslong as you don't do design on the brink of maximum.

For bass, you'd actually need 'clean' power and if you'd want that to sound like bass from the 70's you may just overdrive it use flatwouonds and wear a moustache.

Not that wearing a moustache approaches any wimp status considering LEMMY.........


My advice is to have a qualified tech have a look at your unit to see the realms of what can be done and considere someting higher powered.

Yikes to my memory when my bassist got an Ampeg 400 transistor power it went so clear while also to the point I'd feel exhausted as the power just sucked all air outof my lungs while it still was clean and stable.

I would recommend you check out the Ampeg's but for the sake of your guitarist's and fellow mucisians be modest on volume.
If you want to get a headace on a constant status blast the EBS, which is just as gruesome but more hightech than the Ampeg.


Hey BJ,

The idea of the external fan is to remove the hot air from the rack- even if the internal fan was removing hot air from the amp chassis, the hot air filled the rack, only hot air can be drawn back into the amp. I don't really have a need for bowel movement inducing volume, just clean headroom. When I intially got the amp I was running 2 cabs, one could handle considerably less volume than the other, so I needed a "stereo" amp- this fit the bill, headroom and 2 seperate output sections.
What about Hartke?Or Mesa?
Oddly enough, I just had both a Mesa Bass 400+ and a Hartke 7000 for an extended "tryout" period. Both were great heads, but neither gave me the tone I was looking for.

Here you can see the Hartke, and on the back see that each section side has a vent for cooling to work in conjunction with the fan...

http://images.lilypix.com/albums/userpics/10038/normal_Hartface.jpg

http://images.lilypix.com/albums/userpics/10038/normal_hartback.JPG

[TeleVision]

I guess I was lucky my SWR-400 lasted almost 20 years with little more than a tube replacement and making sure it could breathe.

I have had an SM-400 for about 12 years and, ditto, no problems at all. Maybe I was just lucky and got a good one, but I also always left space above it in the rack. Tonally, though, I have never loved it. I used to run it's power section with an Ampeg SVP-Pro pre and I really liked that, but I had to Ampegs and on each one the input jack failed and when I opened them up to repair/replace, found I could not manage the fact that they were sealed units mounted to the PC board. So I went back to the SWR preamp section which is not as bad as I remembered.

But as with some of the other posters here, I would prefer an Ampeg.

[Fuchsaudio]

I have had an SM-400 for about 12 years and, ditto, no problems at all. Maybe I was just lucky and got a good one, but I also always left space above it in the rack. Tonally, though, I have never loved it. I used to run it's power section with an Ampeg SVP-Pro pre and I really liked that, but I had to Ampegs and on each one the input jack failed and when I opened them up to repair/replace, found I could not manage the fact that they were sealed units mounted to the PC board. So I went back to the SWR preamp section which is not as bad as I remembered.

But as with some of the other posters here, I would prefer an Ampeg.

I've heard this before. Although I never measured it, Larry Hartke ( a local friend of mine), insists it's frequency response is "like a mountain range". I used it for years with the 4x10 SWR cabs, an Alembic bass, and liked the tone with it fairly flat. Never struck me as bad tones. I later tweaked mine to add a subsonic filter (Steve Rabe was always thrilled he had no low end limits in the amp), as I never liked the cone flap. I also added power supply capacitance, as I felt it was too low for the wattage it put out.

I later switched to a separate power amp and preamp, and only then realized how much more tone I could get from a rig.

I always knew I needed strings when I started raising the treble to compensate.

The Hartke heads are reputedly the "largest selling bass amp of it's kind ever..." according to Larry. More than SVT, more than SWR, Eden, etc. Average build quality, but the fan points out the back and they run fairly cool for the wattage. Cannot beat the price/wattage/ratio.

Maybe someone will make a real "boutique bass amp someday...."...lol:RoCkIn

[drbob1]

I mostly use the GT preamp to record and consistently get great tone (at least the bass players I've worked with seem happy). For actual bass use, I plug it into a Mesa 2:90 set on "modern" for good attack, and run that into a JBL Cabaret cab with an E130 or two (good for 105 dB/watt so the equivalent of 700+ watts of modern power if I add it up right). Sounds good to me...

[aeolian]

Hartke is #1? The base bass amp around here is typically a GK. RB400 or one of the larger ones.

[The Golden Boy]

Maybe someone will make a real "boutique bass amp someday...."...lol:RoCkIn

Glockenklang...

http://www.glockenklang.de/en/products/products_bass.htm

http://reviews.harmony-central.com/reviews/Bass+Amp/brand/Glockenklang

[Valtiel]

I too have had the pleasure of having my beloved SM-900 shut down on me during a gig. Thank god I had a backup. It turned out to be a bad PC preamp board though which I got fixed. I never had any problems with it BUT I drilled holes in the side of my SKB rack next to the vent AND had an external fan going at all time. The amp still ran very hot but never shut down on me. I eventually sold it and got a Mesa M-pulse 600 which blows it out of the water.

[Jon]

Can anyone recommend a good bass amp for someone just starting out gigging on bass? Most of the bass players I know are using 300w+ rigs but I don't want to spend big money when it's not my main instrument. However. most of the cheaper bass amps (usually combos) are relatively low powered and we don't have bass bins with our PA so main volume needs to come from the backline. What is the minimum wattage of bass amp that is useable for small to medium pub gigs?

[The Golden Boy]

Personally, I think 300w SS is perfect for that.

Speaker wise- I always say 10s for volume, 15s for tone. If you're looking to project, score a used GK 800 RB and run it through a quality 4x10. Add a single 15 later on.

I personally prefer the sound of 15s.

[The Golden Boy]

I eventually sold it and got a Mesa M-pulse 600 which blows it out of the water.

When those M-Pulse heads came out- I couldn't be peeled away from them at the Mars Music. Even with out the graphic EQ, the thing sounded boner inducingly awesome. I've never seen anyone playing them out, though. I like the concept of the Mesa Big Block- as well as the huge ****er they have now.

A lot of what I used to consider essential, isn't anymore. I really needed a head that could run 2 cabs on seperate volumes- now my main cab is a 2x15 and I've never had call to run any more than that. EvAr.

[aeolian]

Can anyone recommend a good bass amp for someone just starting out gigging on bass? Most of the bass players I know are using 300w+ rigs but I don't want to spend big money when it's not my main instrument. However. most of the cheaper bass amps (usually combos) are relatively low powered and we don't have bass bins with our PA so main volume needs to come from the backline. What is the minimum wattage of bass amp that is useable for small to medium pub gigs?
Try a GK RB400. 250W You can get used one's pretty cheap, and they're indestructible. I've run one so hot you couldn't comfortably touch it and it still kept going.

[Fuchsaudio]

Try a GK RB400. 250W You can get used one's pretty cheap, and they're indestructible. I've run one so hot you couldn't comfortably touch it and it still kept going.

Cannot agree at all. I fixed more 400-RB's and 200's when I did service than any other bass amp. At the time SWR wasn't as big as it became, so I cannot compare, but I never repaired an amp that died as badly as GK's did. Many of the GK's actually had components flame out and burn the PC boards, to the point where we had to get new power amp boards from GK, as the old ones were no longer fixable. Maybe they eventually figured it out, but back then they were not happy about improper loading or getting too hot.

The Mesas are okay, the Harktes are decent, heck even a Behringer, but man GK, nah....

[ChickenLover]

Thought I'd share this here, I'm not a bass player though.

Bass player from a previous band used to use a 1x15" cabinet with a 2x10" w/horn cabinet on top of that. But his little 'secret' for getting it to sound best was using different impedance cabs. IIRC, the 2x10 w/horn was 4 ohm and the 1x15" was 8 ohm but I'm not sure...I think he said it was too boomy with the 1x15" at 4 ohm. He had a great tone.

[The Golden Boy]

back then they were not happy about improper loading or getting too hot.



That's the knock on the GKs that I've heard the most- that they're more sensitive to running an improper load. The "bass" channel handles a 4 ohm load and the "high" channel only handles an 8 ohm load- if you overload either channel, the amp doesn't like it and it will go. I attribute that to being passively cooled. If it's run like it's supposed to be run, it'll run warm, but there's nothing forcing air over the cooling fins or internal components. I think the 1001 has that addressed.

[agreatheight]

There are 4 pages of responses here, but I'll drop in my .02!

I've been playing SWR for years, never had a problem (Bass 350). I always leave the space above my amp empty - I think this pretty much solves any problem (I do this with EVERY hot running rack item I own, better safe than sorry). If that doesn't cut it, leave two empty and install a bank of cooling fans to blow/suck the heat out. It'll for sure take care of it.

Peace.

[John Phillips]

Personally, I think 300w SS is perfect for that.

Speaker wise- I always say 10s for volume, 15s for tone. If you're looking to project, score a used GK 800 RB and run it through a quality 4x10. Add a single 15 later on.

I personally prefer the sound of 15s.
That's funny, that's the exact opposite of what I've found...

For years I always thought I prefered 15s over 10s - I liked the depth. To be fair, that sound suited the bass player in my band too. Now I've started playing bass again myself, and tried a lot of different rigs in various practice rooms, I've found (somewhat to my surprise) that I sound closer to how I want through 10s... it's not just a tone thing, it's more 'speed', or 'punch' - the 10s really deliver in the low mids and sound much tighter, whereas 15s sound deeper but looser and more hollow, and can get blurry when driven hard.

The 15s are definitely more sensitive and louder. This isn't too surpriseing when you look at the figures for individual speakers. Even adding four 10s together doesn't get you back the same efficiency as one 15 in a properly-designed cab that doesn't restrict it too much. (My old Marshall cab with a 15" Celestion Sidewinder was WAY louder than the Trace Elliot 4x10" I've got now.)

But, I do agree that about 300W solid-state is about right - at least through a 4x10". The best little set-up I've tried so far was an Ampeg B1-RE through their 4x10"+horn. Even if I was running it with the limiter light on most of the time ;).

I like the look of the new Mesas, too... one would go nicely with my Trem-o-verb :).

[Funky Chicken]

Wow, am I in the minority here.

I bought an SWR Studio 220 in the spring of 1992 and proceeded to gig the living crap out of it for 12 or so years. Never quit once. Original 12AX7. Never even blew a fuse. I preferred the lower wattage because I was feeding a PA and I wanted to hit the preamp section hard.

I also have a mid '70s GK 400B that has been dragged around the US and used as a bass head and a slave to power monitors on occasion. I bought it used for $240 in 1979 and have done NOTHING to it. I'm not a fan of their recent stuff either, but they used to really put them together.

[The Golden Boy]

That's funny, that's the exact opposite of what I've found...

For years I always thought I prefered 15s over 10s - I liked the depth. To be fair, that sound suited the bass player in my band too. Now I've started playing bass again myself, and tried a lot of different rigs in various practice rooms, I've found (somewhat to my surprise) that I sound closer to how I want through 10s... it's not just a tone thing, it's more 'speed', or 'punch' - the 10s really deliver in the low mids and sound much tighter, whereas 15s sound deeper but looser and more hollow, and can get blurry when driven hard.

The 15s are definitely more sensitive and louder. This isn't too surpriseing when you look at the figures for individual speakers. Even adding four 10s together doesn't get you back the same efficiency as one 15 in a properly-designed cab that doesn't restrict it too much. (My old Marshall cab with a 15" Celestion Sidewinder was WAY louder than the Trace Elliot 4x10" I've got now.)

But, I do agree that about 300W solid-state is about right - at least through a 4x10". The best little set-up I've tried so far was an Ampeg B1-RE through their 4x10"+horn. Even if I was running it with the limiter light on most of the time ;).

I like the look of the new Mesas, too... one would go nicely with my Trem-o-verb :).

Here's the thinking behind my theory...

A good 4x10 will safely handle roughly twice the power that a good single 15 cab can safely handle (as I've unfortunately learned from experience). There's more speaker space available, and more magnets per surface area. If the amp is EQ'd for a good stage mix (heavy on the mids), those frequencies are better suited for 10s, and the "immediacy" of the 10s coupled with the "standout" EQing, make the 4x10 a better "live" cab for a lot of people.

While it's nice to have the punch of 10s, I prefer to be eveloped by the depth of 15s. They're still quick enough to be distinct, but not as punchy as a 10 or 12 (although I'd like to play with a 4x12 that's designed for bass and can handle the power and low end), and not as flubby as an 18.

Do you think some of the apparent "loudness" is a result of efficiency, frequency spectrum or impedance load?

[PB+J]

I hate SWR stuff--I've never been able to get a sound I like out of it. There's some kind of horrible styrofoam midrange thing going on that just irks me.
I had a redhead, a working man's 12, a workingmans ten, and a goliath II jr. cab--hated them all, and I kept trying really hard to like them

They work well for many people though, so it''s probably me and not the gear

[jokerjkny]

(...)
It comes down to poor design with the SWR. No rack unit should be designed with a critical cooling vent anywhere other than on the back or front, because it must be assumed that it will be mounted in a rack! I suspect the cooling is inadequate for the power that amp dissipates anyway - the whole thing looks like some components, heatsinks and a fan just thrown in a case, not properly designed with an effective ventilation path.

i dunno if steve rabe is known for making poor designs. rather, i'm thinking its shoddy parts and manufacturer of the company he left behind.

heck, i dont blame him for leaving with the crap that SWR's pumping out these days. plastic faceplate on the mini'mo and mo'bass? cmon...

heck, the website's even down. :rolleyes:

[jokerjkny]

Wow, am I in the minority here.

I bought an SWR Studio 220 in the spring of 1992 and proceeded to gig the living crap out of it for 12 or so years. Never quit once. Original 12AX7. Never even blew a fuse. I preferred the lower wattage because I was feeding a PA and I wanted to hit the preamp section hard.
(...)

i think you might have a coveted "pre Fender buyout" amp. heck, you actually might have an amp from the "SWR Engineering" days before they became the larger "SWR Sound". :cool:

[Mikebass]

I've heard nothing but bad things about the "chrome" models.
Now the models where the logo was CNC'd into the face of the amp (or "BlackFace 900") always worked good.

I had a BlackFace 900, SM400s, and both worked flawlessly for years.
I loved the old SWR tone, the newer ones IMO just sound different.

BTW, HEY JokerJKNY!!!!
Notice a few TB'rs here now?!?

Hehe!!!!

[jokerjkny]

hehe,

we're takin' over... :cool:

[kipknee]

Cannot agree at all. I fixed more 400-RB's and 200's when I did service than any other bass amp. At the time SWR wasn't as big as it became, so I cannot compare, but I never repaired an amp that died as badly as GK's did. Many of the GK's actually had components flame out and burn the PC boards, to the point where we had to get new power amp boards from GK, as the old ones were no longer fixable. Maybe they eventually figured it out, but back then they were not happy about improper loading or getting too hot.

I must've had a good one then. I bought a 400RB used in 1987 and played it regularly until 1995. Zero problems. AFAIK, the person I sold it to is still using it. Sadly, like with many other brands, I've heard that more recent versions of this amp were not built that well.


The Mesas are okay, the Harktes are decent, heck even a Behringer, but man GK, nah....

Not a fan of Mesa bass amps. One of the gigs that I played had a Mesa Walkabout as the house amp. It had a very uninteresting tone that I disliked greatly. Towards the end of that gig, I would just bring my Eden Highwayman head and plug in to their cabinet.

[Festus]

Well, I used a variety of SWR heads over the years, and the SM-400 (and later the 500) was very reliable and sounded pretty good. The SM-900 would always clip, and occasionally shut down. Extremely annoying, so I quit using the 900. This was all with pretty regular touring. I'd have no qualms about using their new SM-500.

Haven't played any SWR amps since Fender bought them out, though. I've been using a Warwick Quad VI (discontinued, unfortunately), and soon their TubePath 5.1.

[big mike]

Yorkville made a KILLER amp head a few years back, might still. 300B or something? Just killer sounding.

best other tone i like (besides full blown SVT) was a demeter preamp into a crown poweramp.

I always wanted to like SWRs. The cabs aren't bad though.

[big mike]

Cannot agree at all. I fixed more 400-RB's and 200's when I did service than any other bass amp. At the time SWR wasn't as big as it became, so I cannot compare, but I never repaired an amp that died as badly as GK's did. Many of the GK's actually had components flame out and burn the PC boards, to the point where we had to get new power amp boards from GK, as the old ones were no longer fixable. Maybe they eventually figured it out, but back then they were not happy about improper loading or getting too hot.

The Mesas are okay, the Harktes are decent, heck even a Behringer, but man GK, nah....

Yeah I had an 800 RB that blew up a lot. And the new 700's are worse.

[michael30]

A friend had a PS-300 that he was going to fix up for me, until he figured out that it was the 50lb OT that was trashed. I've heard they're supposed to be some really cool amps after tweaking the EQ. The 300 was heavy... I think it ran a 6v6 as a rectifier tube...


I had a PS-300 in the 80's. Great amp, but really heavy. Then I lost all sense of proportion and bought a Marshall Major to go along with the PS-300. I had 2 Marshall 4x12 cabs and two EV 1x18" cabs. The 6V6 in the PS-300 was the phase inverter tube. It didn't have a rectifier tube.

I sold the stacks in the early 90's and bought a Gallien-Krueger SEB 1200 and two Hartke cabs. They have served me well since then.

[dillonfiore]

Not a fan of Mesa bass amps. One of the gigs that I played had a Mesa Walkabout as the house amp. It had a very uninteresting tone that I disliked greatly. Towards the end of that gig, I would just bring my Eden Highwayman head and plug in to their cabinet.

I have a mesa bass amp and I love the tone. I did have some QC issues with it though. The input jacks went out one time(which mesa fixed for free eventhough I bought it used) and the Transformer came loose one time and unplugged some wires on the inside(simple fix, but a pain in the @$$ none the less). Tone wise I love it. Given I like the eden travler more, but the mesa still sounds good to me.

[The Golden Boy]

I had a PS-300 in the 80's. Great amp, but really heavy. Then I lost all sense of proportion and bought a Marshall Major to go along with the PS-300. I had 2 Marshall 4x12 cabs and two EV 1x18" cabs. The 6V6 in the PS-300 was the phase inverter tube. It didn't have a rectifier tube.

I sold the stacks in the early 90's and bought a Gallien-Krueger SEB 1200 and two Hartke cabs. They have served me well since then.

A PS-300 and a Major... together you're talking about 250 pounds of amp... Ouch. You, sir, are a madman!!! :dude

[tebo1018]

Since you love SWR so much, what do you think about Eden gear?

[John Phillips]

Since you love SWR so much, what do you think about Eden gear?
I had to fix one recently. I would say the build quality was OK, but not outstanding. Like the SWR at the start of this thread, it was also badly-designed (IMO) in that the main cooling outlet is via vents at the tops of the sides, which means that when mounted in a rack enclosure it stands a fair chance of overheating. It didn't seem to run anywhere near as hot as the SWR gear does though, and in fact the fan is only used once some temperature sensors on the heatsinks kick in, so I suspect the output stage is a lot more conservatively spec'ed (I didn't try to overheat it to test this).

The thing I really didn't like - and why I had to fix it - was that there are some high-power resistors mounted on a PCB in pairs, soldered only at one end, with the other end connected only to the other resistor in the pair. The whole mess is then 'stabilised' with hot-melt glue (which is a good thermal insulator BTW... bad). Of course, the joints under the board had desoldered themselves and cracked. I don't want to condemn Eden out of hand though, since I'm not 100% sure the amp was built like that - it's the only one I've seen inside, and it could have been a previous repair... although if so, the original scheme couldn't have been much better.

[glaswerks]

I don't think I saw it mentioned in the thread, the SWR failure mode (my SM500 has thermaled on me several times) is a thermal switch that is mounted in the power transformerto prevent it from burning up. According to Mercury Magnetics (the manufacturerer of the power later power trannies) the transfomers are (or at least were) seriously under rated for the application. The amps do not handle 4 ohms in bridge mode at all.

I spoke with John Willis (VP sales SWR) at NAMM this year and according to him they have corrected the problem. I still need to contact their service group and see if I can purchase the upgraded tranny.

Edit........

FWIW, the old SWR's did not have an internal thermal switch in the transformer.

[The Golden Boy]

Just because this thread got bumped, I should mention I used this at a show 2-3 weeks ago and it went into thermal protect on the very last note of the set. Seriously, the last note.

I don't think I saw it mentioned in the thread, the SWR failure mode (my SM500 has thermaled on me several times) is a thermal switch that is mounted in the power transformerto prevent it from burning up. According to Mercury Magnetics (the manufacturerer of the power later power trannies) the transfomers are (or at least were) seriously under rated for the application. The amps do not handle 4 ohms in bridge mode at all.


FWIW, the old SWR's did not have an internal thermal switch in the transformer.

That's a good thing to know right there- about the 4 ohms in bridged mode. I did a little dinking around trying to remember everything that's been done with this amp. As I recall- the first tech set the fan to run all the time, and when it would normally turn on- it turns to a higher speed. Not exactly sure how he did that- but I ran it with the cover off and watched- sure enough...

As I've got 3 fancy pants gigs this week, I'd much rather use the SWR than the Seymour- but I'm going to have to bring the Seymour as a backup. If the SWR goes out the first night- it's staying home until it's running right.

I plan on using my Triad cab and I'll just use one side of the stereo (left side), and we'll see how that swings. I used it at a 3 hour rehearsal on Friday with the Triad on one side and an 8 ohm 1x15 cab on the other. I've got another big rehearsal tonight, so this is kind of a test on that...

[glaswerks]

Try adding another fan, this one aimed to direct air across the transfomer. It just might help.

Gary

[The Golden Boy]

So here's the update...

Last week I had 3 3+ hour, outdoor, very hot gigs. I used my Triad cab, the SM-900 and brought the Seymour Duncan 300x300 as a back up.

I usually run it bridged into a either 4 or 8 ohm cab- the last time I used it at a show, it went into thermal somewhere between 1-1.5 hours. I decided to try a few different things. One, run the cab out of one side of the stereo- in effect- only working about half the amp. Secondly, I took the cover off the amp. I realize that's kind of a gamble. I know taking off the cover exposes the amp's components to whatever is in the rack, and having no cover messes up the designed airflow pattern and can be a bad thing. HOWEVER, it's overheating anyway, there's 4 components that generate a lot of heat and it's designed cooling system isn't working- I have a spare head, although the ideal situation is to do this at rehearsal- I need more volume at the outdoor gig than I need indoors...

The first two nights, everything was completely fine, I checked it between sets and it was "warm" but not hot- even on the heat sink, and even at the end of the evening. Keep in mind, it was warm and humid, and outdoors- so I was using a little more volume than I normally would be- and the amp was handling it just fine. On the third night I decided to run the amp bridged to see what would happen. With the cover off, running the amp bridged, and louder than it's normally run, with the same impedance load it's usually presented with... I checked the amp a few times during the first set and at the break and a few times during the second set and when we finished... The amp ran fine, a little warmer than running one side of the stereo, but easily what I would consider "normal operating range" of temperature.

So what I'm going to do at this point is to find a grate of some sort that will allow ventillation of the chassis innards, but not allow things to fall into the amp.

We'll see what happens here...

[big mike]

Jeez what a pain in the ass. Hope you've at least got it sorted.

[The Golden Boy]

Jeez what a pain in the ass. Hope you've at least got it sorted.

As soon as I can get the bank to get something else that sounds as good or better, it will be sorted.

[Bassomatic]

Just about to pick up my old #1 SM-400 from the shop. It went down over a year ago, and was in the shop 1x previously. This after years of many shows and a couple tours. For me.

Bought it from Brad Houser who had toured the hell out of it, as well as used it for cutting the New Bohemians stuff. Not too shabby, reliability- wise, though it's got at least one mod (adding of early "presence" knob - unlabelled). Does an early and/or endorsement rig equate to more reliability?

[The Golden Boy]

Does an early and/or endorsement rig equate to more reliability?

My amp is a mid-late 2001 amp. If you look at the Harmony Central reviews (http://reviews.harmony-central.com/reviews/Bass+Amp/product/SWR/SM-900/25/1), there are 2 reviews prior to summer of 2001, both are good reviews. The users who mention having older amps all have good reviews. Out of the 15 reviews, at least 5 mention critical overheating and blowing fuses and failing. There's a few more that mention how hot the amp gets.

My guess is that when they had a good idea they were going to be selling out to Fender, something changed with the amps. Someone mentioned a change happening about the time they went from SWR Engineering to SWR Sound... I don't know anything for real- just that it's about in the neighborhood as the same time period as my amps were made and I've had nothing but heartache with those amps.

[ibblue2]

What's the concensus on the Thunderfunk TFB550-B ?

[The Golden Boy]

I haven't heard a bad thing about it.

Your best bet is to ask that question at Talk Bass, there's a much larger sampling of bass players there.

[Bassomatic]

My amp is a mid-late 2001 amp. If you look at the Harmony Central reviews (http://reviews.harmony-central.com/reviews/Bass+Amp/product/SWR/SM-900/25/1), there are 2 reviews prior to summer of 2001, both are good reviews. The users who mention having older amps all have good reviews. Out of the 15 reviews, at least 5 mention critical overheating and blowing fuses and failing. There's a few more that mention how hot the amp gets.

My guess is that when they had a good idea they were going to be selling out to Fender, something changed with the amps. Someone mentioned a change happening about the time they went from SWR Engineering to SWR Sound... I don't know anything for real- just that it's about in the neighborhood as the same time period as my amps were made and I've had nothing but heartache with those amps.

Sounds like you may be on to something.

For my part, just got my old baby out of the shop, and looking forward to bringing it to my rehearsal studio for a full workout tomorrow. I've been missing her badly.

[Bassomatic]

Well, she's everything I remembered. Nice to have some serious clean headroom on hand again. Lows sound lower, tone knobs and paragraphic eq are so much more precise for dialing in what I want to hear. Sounds swell at moderate volumes, and terrific at LOOOUUUD levels (running a 4x10" Goliath, sometimes with an added Goliath Jr. II).

If reliability is as it was, I may sell my smaller Trace V-Type combo rig (which has been rock solid and trouble free for years of rehearsal and occasional gigs).

[The Golden Boy]

Yesterday my brother in law asked me to give him a hand at his storage shed. He gave me a top panel that fits the SWR head from side to side, but it's a little short from front to back. I decided to drill a few hundred holes in the panel, drill new holes to match up to the chassis and attach it. I was playing a 4 ohm cab bridged through the amp and after the fan turned on high, you could feel the hot air being pushed out of the amp. I could also feel the amp drawing air from the top.

The manual says to not run the amp with the cover off. As is, it's not drawing enough fresh air in and it's not expelling enough hot air. I've used the amp without the cover a few times, and it's performed great. The way I figured it, as long as there's something keeping things from getting caught into the works of the unit, there's more air going in and out of the chassis.

The other thing he gave me was a Mesa Boogie Bass 400+.

:D

It needs some work to be operational, but it'll be a cool project.

[jzucker]

just get a markbass and fuggetaboudit

[John Phillips]

The other thing he gave me was a Mesa Boogie Bass 400+.

:D

It needs some work to be operational, but it'll be a cool project.
At least you have a proper amp now - one that's meant to get hot and can do so without destroying itself ;).

:)

[TedintheShed]

SWR made great stuff when Steve Rabe owned it. My dream rig was an SM-900. They had a great hi-fi tone, yet maintained a darkness about it.

Then he sold it to some accountant- it kind of became mediocre. Then it was sold to Fender 3 or 4 years ago. Now, I wouldn't touch that crap pile with a 10 foor pole.

[high mileage]

Not quite the same stuff it used to be... I have a 10-year old Super Redhead (right after the "Super" came out) and never had a problem with it. Well, honestly I did take it back shortly after I bought it because the fan was fairly loud but they said it was normal and you'll never hear it when playing. I learned to live with it.

What is it with bass amp builders putting vents on the side of a case designed to be rack mounted? I mean really, it's just plain stupid. I had an SVT4 and cut the side of the rack out which is where the fan blew the hot air. That would have been within 1/2" of the edge of the rack I was using, and with a band that always gets yelled at by our sound guy for too much stage volume, it probably woulda quit at some point. I started looking at replacements and found this with Genz Benz's big head too. At the time I didn't look at SWR again because I didn't want something as clean as my SRH.

If you need a lot of power, the best bet is a pre and separate PA system power amp. QSC's are legendary for lasting forever but I have a Crown XTI that puts out a ridiculous amount of power, cools front to back, and weighs 19 lbs. Throw in whatever preamp you want and you've got a killer rig that won't shut itself down. Want a different sounding rig? Keep the power amp and get a different preamp. Pretty easy to have a spare too, if you use a tube pre - just throw a second one in the rack.

[Red Planet]

Lets see.

The GK stuff is crap for sure.

I had the Big Hartke and had no issues with it.

The QSC 2400 watt Power Amp makes one hell of a Bass Power Section.

The Mesa 400+ is by far the best unit I have ever played for that old fashioned tone and plenty of power.

The old Trace Elliot Preamp was great for getting a Clean sound then slamming a Poweramp.

I currently use an Ampeg SVT 3 Pro into an Ampeg 4X10HLF and love it. Its plenty loud will get gritty if I need it and easy to move.

Im trying to rember the SWR stuff at one time wasnt there a small production shop building those for Fender and isnt that the same shop that builds the 65 Amps. I may be wrong on some of this but rember it from somewhere.

I've had toooooo many Bass Rigs that when you really need them they overheat and shutdown and that gripes me.


Being the Gear Freak I am when I used to play a lot more Bass I used an origional Tobias 6 String into a Mesa Boogie 400+ going from the speaker out to a Boogie 4x10 and from the Slave out to a QSCRMX 2400 into a Boogie 2x15 and man that thing would make you sick.

What a nut I was.:D

Whatever I use if its rack gear I put it in a rack that has space on all sides and space between units.

[big mike]

The guy who used to work for SWR is doing some stuff for 65amps.
Don't think they're actually building for Fender now though.

Get a demeter preamp, run it into a Crown or QSC poweramp and call it good.

[Red Planet]

The guy who used to work for SWR is doing some stuff for 65amps.
Don't think they're actually building for Fender now though.

Get a demeter preamp, run it into a Crown or QSC poweramp and call it good.

Fender may have went the way of all the other little fishies going to overseas production like say Ampeg. I be glad mine twas made here aforin all the low cost crap. Ha I even got one of the Power Blocks befor they axed them.

[big mike]

Hey I loves my powerblock!

My bassplayer's rig is 'PRE LOUD' (mackie) Ampeg. :dude:

[Red Planet]

Hey I loves my powerblock!

My bassplayer's rig is 'PRE LOUD' (mackie) Ampeg. :dude:

I was playing my P B tonight. Sounds freakin great!:AOK

[Robal]

SWR made great stuff when Steve Rabe owned it. My dream rig was an SM-900. They had a great hi-fi tone, yet maintained a darkness about it.

Then he sold it to some accountant- it kind of became mediocre. Then it was sold to Fender 3 or 4 years ago. Now, I wouldn't touch that crap pile with a 10 foor pole.


Here's the history: Steve Rabe and the other founding partners of SWR Engineering sold their interests to Daryl Jamison, who was also one of the original partners in SWR Engineering. The company name then changed to SWR Sound. Daryl is an accountant, as well as a bass player who majored in music at USC. He built up the company with one primary goal: to be profitable and to resell it for a lot more money. He succeeded in doing that and in selling the company to Fender. I would have to agree that there is a difference between the original SWR Engineering products (1984 - 1997) that Steve personally designed and quality controlled and the later products released by SWR Sound. Honestly, as one of the founders of SWR with Steve it pains me a bit to see so much criticism of SWR gear, since we really did care about what we were selling and spent a lot of time road-testing it for durability, but I can't support the stuff that was made later. I know what the company's priorities were. I have several of the old amps and cabs and would never sell them. For new bass gear, however, I would look elsewhere.

[John Phillips]

Here's the history: Steve Rabe and the other founding partners of SWR Engineering sold their interests to Daryl Jamison, who was also one of the original partners in SWR Engineering. The company name then changed to SWR Sound. Daryl is an accountant, as well as a bass player who majored in music at USC. He built up the company with one primary goal: to be profitable and to resell it for a lot more money. He succeeded in doing that and in selling the company to Fender. I would have to agree that there is a difference between the original SWR Engineering products (1984 - 1997) that Steve personally designed and quality controlled and the later products released by SWR Sound. Honestly, as one of the founders of SWR with Steve it pains me a bit to see so much criticism of SWR gear, since we really did care about what we were selling and spent a lot of time road-testing it for durability, but I can't support the stuff that was made later. I know what the company's priorities were. I have several of the old amps and cabs and would never sell them. For new bass gear, however, I would look elsewhere.A sad and fairly typical story... something similar happened to Trace Elliot.

(Original designer left, accountants got in charge, product range massively expanded, design and build quality went down the pan, warranty repairs went through the roof, sold to Gibson leaving them to pick up the pieces. Sound familiar? :()

I love old Trace gear up to and including the Series 6 amps, but after that I wouldn't recommend one. Even the flagship V8 400W tube head I had on loan for a while recently was poorly designed and built, and caused problems. Luckily, Gibson sold the brand to Peavey a couple of years ago and according to someone I talked to at Peavey the new Trace gear has been re-engineered from the ground up for quality. (I haven't played one yet though.)

[The Golden Boy]

Honestly, as one of the founders of SWR with Steve it pains me a bit to see so much criticism of SWR gear, since we really did care about what we were selling and spent a lot of time road-testing it for durability,

Robal- I'm sorry my public opinion of the SWR amps I've owned has been... "harsh." But I believe, with the money, lost gigs, lost time, heartache and embarassment those amps cost me- I've earned the right to bitch. On the other hand, they both sounded awesome- which makes finding a replacement THAT much harder. As I mentioned before, it seems that people that have the older amps are happy with the quality and reliability of their amps- I think the care that was initially shown in the design and development are still fairly evident (with the exception of the cooling)- just the "recent" manufacture of the amps doesn't live up to what they were.

[The Golden Boy]

http://img260.imageshack.us/img260/8057/swrfrontgb1.jpg


The panel doesn't extend all the way to the front, however, the open portion is under the tuner in the rack.


No making fun of my awesome "drilling in a straight line" skillz.

http://img210.imageshack.us/img210/9913/racksidegs7.jpg


This Saturday I've got a 3 hour show- two 1.5 hour sets. Chances are, the guys are going to want me to bring 2 cabs- which is fine- it'll probably be less of a load on the amp than one cab bridged. I'm thinking of turning the fan around and blowing it into the rack. We'll see.

[frankencat]

My bass player's SWR 750x just died and I am trying to get it fixed for him. This thing has very little playing time on it and looks like new. It worked at our last show and that was that. It did seem like it should have been louder though. I checked all the simple stuff, fuses, tube and they are all good. I get input and hear sound at the headphone out but nothing at the speaker outs. I guess it's time to send it off. :(

FWIW, I have an Ampeg SVT 3Pro that totally smokes this thing.

[Bryan316]

SWR was good when David Nordschow was designing their gear.

Those days were DECADES ago.



There's a good reason why SWR sucks.

[aaland_brian]

I had a SM-900 years ago, it always overheated and ended up blowing the power transformer one day. even on it's best day it didn't seem to have as much output as it should have for 800watts. I bought a mesa m-pulse one day and the sm-900 made it to ebay.

[testing1two]

I had an SM900 for years and played hundreds of shows without a single thermal shutdown. The secret? I always left an empty rack space directly above it and I used an external fan for outdoor gigs.

I know this thread is long since retired but it begs the question, "is a rack tuner really that important?"

Or maybe I was just lucky...

[joemesser]

I agree, you just need more space in your rack. It sounds like it's probably a ventilation issue. Your stuff doesn't have any room to breathe. Amps need to breathe.

Shameless plug time: I have a beautiful, brand new, all solid wood 5-6 space rack case by JDesign cabs for sale. Plenty of room on top, bottom, and the sides for ventilation. PM me if interested.

[Rod]

Last night I had a show and my SWR SM-900 went into thermal shutdown. Again.

The SM-900 was SWR's "flagship" model. It's very powerful, it's got plenty of headroom, a very controllable EQ, it's light, and it sounds awesome. It's a phenomenally great sounding amp. But it has a habit of "blowing up." It's not like I'm pushing it really hard (bass at 12:00, pre around 11:00, master vol at 9:00) and it's well within it's impedance range (an SWR 2x15 cab in bridged mode). I had issues when I first got the amp, little QC things like mystery screws rattling around in the chassis, improperly wired DI, bad fuse well, bad LED/cold solder joint... So I figured it was just another of it's quirks that needed to be fixed up. I had it in to the authorized tech's shop far too many times- what it came down to (for the overheating problem) is that the air isn't flowing like it should. It's mounted in an SKB rack, as it's designed to be used in a rack, and it would always overheat- sometimes blowing output fuses, sometimes just going into thermal shutdown. In any case, it was a $1200+ amp, and it was completely and totally unreliable.

The amp is designed to passively draw air in the back, force it through the heat sinks towards a grill on the side of the amp. That design doesn't take into account of being used in the confines of a rack case. The wall of the rack is less than an inch from the wall of the amp, and the rack entirely encloses the amp. What that means is that the hot air that is removed from the amp chassis gets recirculated into the amp because most of that hot air stays within the rack. Also keep in mind nothing actively forces or pulls air in or out of the amp chassis- there's a fan in the center of the amp that blows it TOWARDS the grill. As the hot air does go out the heat sinks- because the rack wall is so close there's resistance to the air exiting the chassis and a lot of the hot air doesn't make it out of the chassis and keeps getting heated again.

The tech suggested that I get a fan to either blow air into or remove air from the rack. So I got a fan from Radio Shack and mounted it onto the upper rack rail in the back. It removes the hot air that builds up in the rack. It's done well in the past 5 years or so. The amp has never overheated, blew a fuse or even run hot since then. I used the amp a lot, it was used several times a week for rehearsal, gigged every few weeks until last year. For the past year it sees use about once a week and gigged about once a month.

Last night in the middle of the set, probably an hour and a half in- it just stopped in the middle of a song. I still had power to my power supply, but the amp LEDs were off... As soon as I touched the rack handles I knew what had happened again. It was my first show with this band, and not only was I embarrassed, but absolutely livid that it would happen again. As awesome as this amp could be, I ****ing hate it.

The SWR SM-900. Notice the covered SWR logo- because of their 'awesome' "customer service" I refuse to leave those logos visible and do any sort of advertising for them:

http://images.lilypix.com/albums/userpics/10038/normal_rackface.jpg

The "guts" of the amp- the long black rectangles are the heat sinks- the fan is just to the right of the heat sinks. The air should be drawn from the vent in the back (at the top of the pic) and then through the heat sinks towards the vent off to the left of the heat sinks. Yeah- That'll work.

http://images.lilypix.com/albums/userpics/10038/normal_SWRguts.jpg

And here's the back of the rack, showing the fan I installed into the rack- it's noisy but until yesterday, it did a wonderful job of removing hot air from the rack and keeping the amp cool. Notice the packages of fuses taped to the wall of the rack- just in case.

http://images.lilypix.com/albums/userpics/10038/normal_rackback.jpg
Buy an Eden and be done with SWR!!

[Sir M]

Nothing fails more than MarkBass... except maybe prayer...

[The Golden Boy]

I had an SM900 for years and played hundreds of shows without a single thermal shutdown. The secret? I always left an empty rack space directly above it and I used an external fan for outdoor gigs.

I know this thread is long since retired but it begs the question, "is a rack tuner really that important?"

Or maybe I was just lucky...

That's an interesting question that I might have thought differently about... I like having the rack mounted tuner. Until I got the rack tuner, I always used my TU-12 with my bass rig- sometimes I'd leave it plugged in, sometimes I'd just tune my bass and be done with it. When I got a rack mountable amp- I wanted a rack tuner- I bought the rack with the intent of getting a rack tuner. None of my basses are particularly unstable holding tuning, and I'm not changing tunings (I used to do drop D tunes throughout the set, not anymore)

Yes, I still have the SM-900. I have a zillion holes drilled into the wall of my rack case. When the amp is going, you can feel the hot air being vented out of the amp- I think the holes are serving their purpose.

I still love the sound of the SM-900, I haven't had much of an issue with overheating in a long time, despite some long, hot, loud shows.

Whether or not there's an open space providing air flow from front to rear in the rack- the big problem is still that the wall of the rack is .5" from the exhaust vent of the amp. I think it's wrong that you'd either have to modify the rack or run the amp outside of the rack to allow proper heat dissipation, but still have the amp need the protection of a rack case.

[Bryan316]

Buy an Eden and be done with SWR!!



HALLELUJIAH!!!

:banana:banana:banana

[Bryan316]

Nothing fails more than MarkBass... except maybe prayer...


What about Vietnamese built Ampegs? HMMM? Even Ampeg themselves have admitted their overseas products are abysmal.

[jay42]

The gut shot shows that it's a remarkably stupid design. I have a QSC power amp where the heat flow is front to rear, not sideways. oi :mob

[Fuchsaudio]

I have an original SM-400 SWR, back when Eden built the cabinets (and possibly the heads). In the 20+ years I've owned it, all I've done is replace the tube. I added my own fan, not because it needed it, but because I saw the newer models had them. One night, our monitor amp died on a gig. We used one channel of the SWR to run monitors, and I played through one channel for bass ! It was hot as hell, but never died in all the years I owned it.

Sad thing is the Markbass stuff I've heard at shows sounds great. I heard 2 4X8 cabinets at the NAMM show, being run by a flea-weight head, played by the bass player from the Tonite show, that sounded awesome. Sorry to hear they don't hold up. They actually manufactured the short-lived "Audiophile" bass amps that were sold by Ernie Ball, years ago.

Current Ampegs are abysmal. The Vietnamese Ampeg's may be one of the death knell's that will fold Loud Technology. They shifted production to Vietnam, at the same time cut off all the warranty stations, and had a failure rate exceeding 75% in the field. Trying to catch up with Mackie apparently. Bean counting MBA's, not Engineers nor musicians.

The bass rigs I hear the most positive reports about these days are the Aguilar amps. We deal with a number of cartage and rental companies. When I asked "whats the most popular bass amp in your arsenal these days", they claim that "their the one to beat". Reliable, good tone, and roadworthy.

[glaswerks]

Andy, I think the SM-400 was one of the last good ones. My SM-500 will overheat anytime I run bridge mode into 4 ohms (it is rated for 4). The thermal switch in the power tranny kicks out.

I keep it safe and run the two power amps separately into 8 ohm cabinets. Not as loud, but never has failed in this mode either...

My main bass rig these days is a Glaswerks one-off bass preamp into a QSC PLX-3000 (I think that is the number) power amp. Light weight with just enough kick :).

Gary

[Fuchsaudio]

People tend to forget that most of the older solid state power amps were never really rated for a 2-ohm load, which is what they see, when strapped for mono at 4-ohms. The load is split. Many amps are not happy about this. I used the 2 4x10 Goliath's , one per side and it was happy. My later rig was 2 2x10 Hartkes on top, with a stereo Ashly amp and the SWR running the Goliath's on the bottom, in stereo with chorus....can you say "Jaco"....now If I could play like him.... :)

Someday, when I grow up, I want to make a kick-ass bass amp (or two) .....still have the SM-400 and 1 of my 4x10s for reference...

[trwigg]

I'm sure I am way out of my league but I have an SWR Workingman 15 combo that I have had since 1998 and it still gets it done. Just sayin'

[Jon Silberman]

I've had my CA Blonde since '99, also never a problem.

[Bryan316]

I run my Eden WT550 at 2 ohms far too frequently to ever have me doubt its stability.

Worst case, I did an outdoor party in August. We were on at 1:00pm. My rig was in the staging area at 11:30am. My amp is inside an SKB US Roto Rack, air tight black plastic. It was a pressure cooker for everything inside the rack. It sat directly in the sun until we set up, with the rack lids still on, just baking. It was 95 degrees in the shade at 11:30am, easily far warmer by 1:30pm.

I opened my rack, plugged things in, running both my 212XLT and my 210XLT, both 4 ohm cabs, for a 2-ohm load. I played a 45-minute set.

My amp never flinched.

That's as extreme a field test as I can think of, to put my rig through. I'll never doubt the integrity of my amp. but I know there's no current SWR products that can be this reliable. I'll dare say, no SWR products built in the last decade.

[Robal]

I have an original SM-400 SWR, back when Eden built the cabinets (and possibly the heads). .

FWIW, Eden never made the heads or any of the electronics for SWR. For just a few years Eden made Goliath cabs for SWR, then SWR switched to local (Southern Cal) speaker cab makers. Eden, which a small pa speaker cab maker, then jumped into the bass gear market, hired an outside amp designer to come up with a bass amp line, and the rest is (old) history.

[realityczech]

FWIW, Eden never made the heads or any of the electronics for SWR. For just a few years Eden made Goliath cabs for SWR, then SWR switched to local (Southern Cal) speaker cab makers. Eden, which a small pa speaker cab maker, then jumped into the bass gear market, hired an outside amp designer to come up with a bass amp line, and the rest is (old) history.


Funny how the truth gets spun over the years eh?
I for one trust your knowledge on the matter.

[Red Planet]

I hope none of this gear fails. :D

Lets see the SWR M2 Preamp hooked to the QSC PLX1804 was my first attempt. at a lightweight Bass Rig after my spinal surgey (life changed after the surgery). The MarkBass LMIII was my second attempt since the first was still a little too heavy. The Genz Benz Shuttle Max 12.0 was my third attempt since it has way more power than the MB but is about the same weight.

Lets see the SWR/QSC Rig 1800 watts of thunda. The MB is 500 watts of pump in a wee tiny package. The Genz Benz is not as cutsy as the MB but pumps 1200 watts out.

I have settled to using the MarkBass pretty much, it's just so easy to move.

The new SWR Gear is cutting egde state of the art. The M2 Pre is built like a tank, quiet as studio gear, does almost everything, and just sounds sooooooooooooo goooooood. The new SWR Golight Cabs (which I have) are best cubic volume/weight/wattage/spl/good price/good tone ratio I have found.



The MarkBass sounds really good (not as good as the Genz or SWR but good) and is such a joy to move. The 3 year warranty you can not beat. If it fails you take it to GC and they give you another one. They are so cheap if it fails on the 4th year you just buy another one. They are built in Italy as well.

I like all of the new Bass Gear. There is a lot of cool things to choose from.


http://img.photobucket.com/albums/v218/RedPlanet/100_0707.jpg


http://img.photobucket.com/albums/v218/RedPlanet/100_0713.jpg

[rsm]

I tried many bass rigs / racks back in the day. SWR, GK, Ampeg, Peavey, Crown, Cerwin-Vega (18" folded horn with the handtruck built in. Still have it at my parents' house, unless they had it hauled away)...

I ran an ADA Bass Rig for years (purchased new in '93; sold in 2009; Thing still looked like the day I picked it up new. Gigged for years in bars and clubs in the Northeast USA, and metro Atlanta GA). Here is a pic:

http://web.mac.com/a_chaoidh/iWeb/Site/ADA%20Bass%20Rig_files/bass-rig-1.jpg

I had a Trace Elliot GP12SMX preamp, that I finally sold once I found a Trace Elliot MP11. I also found an SMX Dual Compressor pedal (same circuit as the GP12SMX in pedal form) that I run in the loop of the MP11. I ran/run these into a Bose L1 system and could not be happier. I keep my MP11 at home now, and I'm using a Tech 21 Programmable Bass Driver DI into the Bose or into FOH direct.

[SGD Lutherie]

SWR was good when David Nordschow was designing their gear.

Those days were DECADES ago.

There's a good reason why SWR sucks.

I know a guy with an Eden, and his amp shuts down if you have the drive up too far.

So it doesn't seem like he did any better with Eden.

Amps shouldn't shut down in normal use.

I was using an older SWR WorkingMan's 300 at a rehearsal studio in NYC a couple of weeks ago. It was plugged into a Bag End cab. Boy that amp sounded so good it made me want to sell my Trace head!

I haven't tried the newer SWR amps lately.

[Brim]

I've never had my Eden shut down. I drive it at 4 ohms all day, master volume between 11 and 12 o'clock. Edens do have a fail safe built in that will shut off the amp when it gets too hot , but seriously it takes a while to get there. Your friend might have been doing something extreme. FYI, my WT550 head will runs 2 ohms no sweat.

I know a guy with an Eden, and his amp shuts down if you have the drive up too far.

So it doesn't seem like he did any better with Eden.

Amps shouldn't shut down in normal use.

I was using an older SWR WorkingMan's 300 at a rehearsal studio in NYC a couple of weeks ago. It was plugged into a Bag End cab. Boy that amp sounded so good it made me want to sell my Trace head!

I haven't tried the newer SWR amps lately.

[Tubevalvemaniac]

I have new SM-900 (2,5 months) with each day 4-5 hours rehearsals and 3 hours gigs (sometimes very loud).
Maybe 2,5 months is not enough long time, but I think I play more than some guys in 3 years, so it is irrelevant.
First of all, sound of new SM-900 is cleaner and deeper than some older SM-900. It is better to my ears and absolutelly fantastic indeed. My nr.1 amp of all times is Ampeg SVT-2Pro that is slightly bigger (11 tubes) in sound and really monster amp.
But I can't say I love Ampeg more than SWR.
I think SWR imporved quality in the last years (last 1-2 to be precise).
It is known that SWR should have a lot of air to breathe. My never failed, even when I was on total edge of its power.
It is hard to find other amp that sound 'better', SWR has all depth, punch, size, cut through saturated walls of sound, EQs are really effective.
For more than 20 years of bass playing, I definitelly came to conclusion that SM-900 and SVT-2Pro are among the best choice money can buy.
Buying new has sense, as they improved some weakness and they can be found at very reasonable price.

[jzucker]

a friend of mine had an swr that would shut down constantly. They gave him the runaround long enough for his warranty to run out then they wouldn't fix it. I would never buy one of their products after that. He played bass in my band so I got to witness the entire debacle...

[The Golden Boy]

Ahhh... my 2 and a half year old hate thread, still going strong...

The amp is still running fine- for all the headaches and embarrassments it's caused me...

It does sound pretty badass though...

[michael30]

I sold the stacks in the early 90's and bought a Gallien-Krueger SEB 1200 and two Hartke cabs. They have served me well since then.

Since we're updating: The Gallien-Krueger died (as well as my Hartke Kickback 120). I'm down to a '68 50W Bassman, which is OK for rehearsals. I think I'll start looking for an old Bassman 135 in case I need to play any gigs.

[alanbass1]

Oh no, not the llama

http://i104.photobucket.com/albums/m187/alanbass1/llama.jpg

[Robal]

Last week I bought a mint condition SWR SM 400s, made in 1997, for $200 at Guitar Center. (It had a bad speaker fuse so it wasn't working right; count on Guitar Center to overlook such things so that the amp sits on the sales floor for months). An SWR tech checked it out for me and confirmed that, with a new fuse, it was operating perfectly. For me, this was one of SWR's very best amps, built when Steve Rabe was still running the company and listening to what bass players wanted. This model does not overheat readily, beause of the lower wattage (500 watts bridged mono), and the flexibility of the control system is the culmination of many years of SWR's responses to the requests of scores of pro bass players. It does what it is supposed to do: provide clean, wide-bandwith bass, with plenty of definition. It's not an SVT or a B-15, nor does it try to be. But for $200 used (and I see moderately used ones selling for even less), it's a very good bass amp. Is there a much better deal, in that wattage category, after all these years? Has bass amp technology "evolved" so much in the last 12 years that these classic amps are obsolete? I don't see much reason to buy a new pint-sized "Class Z" bass amp when you can snag one of these full-featured, multi-plantinum recorded, 500 watt bass amps at such reasonable prices. So, no, I don't hate SWR. You just need to look for the right model (pre-SWR Sound/Fender), at the right price, for the right application -- used, but not abused. As for post-1997 SWR stuff, I have no experience and therefore no opinion.

[clintrubber]

Hi,

Interesting thread !

I have two of those old fanless SWR Engineering SM-400 amps.

One recently stopped working and to my surprise it was because of
the opening of the internal 8A internal fuse.

The lower rated 'external' powerline fuse is still fine, as are
both speaker fuses.

Must admit things were pretty loud then, 4 Ohm bridged use and hmm, maybe the amp detected I played
baritone through it at that time, not a proper bass ;-)

But serious, I'm surprised the internal fuse went and the external one remained OK.

Schematics do say the internal fuse is a FAST-BLO, the 'external' one a SLO-BLO.
But while I don't recall the exact rating of the external one, it's 230V_AC country here.
So the external fuse will be around less than half of that 8A internal one.


Maybe just due to age ? I hope there's not something really serious going on, don't want to fry the power-transformer for instance (likely the type without thermal protection).

OK, I have new 8A FAST-BLO pigtail fuses upcoming, let's see how the amp behaves after a new fuse.

Bye,

Peter

[clintrubber]

BTW, speaking of the SM-400, anybody else also experienced trouble with those FX-loop jack-connectors ? The plastic had become brittle, didn't took much handling to let some connectors fall inside, had to replace...

The FX-loop & X-over I/O is the only spot were those plastic types are used, likely because of their chassis-isolating property. But they're pretty small, the usual isolated types don't fit.

Cheers,

Peter

[Tubevalvemaniac]

Update after 14 months of constant gigging (6 days a week plus studio).
SM900 so far doesn't show any sign of being tired and no single failure.
It should die already, if something was wrong with quality.
I love the amp and it offers unbelievable spectrum of sounds, after one get used with it.
It is never in rack and I don't put anything below it.
In general, seems that YR 2009 SWRs are better than some of earlier years.

[CavePassivePedals]

My 10 year old Goliath Jrs are still going strong.