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Billm
04-18-2012, 03:12 PM
I just put up a page with pictures inside both chassis. I like the Excelsior; it's a cool amp with some very usable tones and I think it will benefit from mods. It's well made; good value for the money.

http://billmaudio.com/wp/?page_id=1203

budglo58
04-18-2012, 04:35 PM
Great pics Bill .Looks like a well built amp. How does she sound?

straightblues
04-18-2012, 04:50 PM
Thanks for the review. I am very interested in the amp. Are they being shipped yet? How did you end up with one?

Webfoot
04-18-2012, 05:25 PM
Curious if it has more mids then a DRRI or is always a scooped sound.

Billm
04-18-2012, 06:03 PM
They're being shipped now. The tone is very straightforward, like you'd expect from a "1950s" amp. It's midrangey, but not honky. Bass response is somewhat restrained. I found the mic and accordion inputs to be mostly useless for guitar. Amps like the Blues Junior and Princeton Reverb have more tonal complexity, more harmonic content. I wouldn't call the Excelsior tone classic Fender. It's neither tweed nor blackface.

It gets pretty darn loud before it breaks up.

You get woman tone by rolling back the tone on your guitar, turning up the volume, and throwing the tone switch to "dark." The contrast between bright and dark is large. It cries for a middle position or a real tone control. Expect to see one as a mod.

The tremolo is deep and throbby. It goes nice and slow, but I wish it would go faster for shimmer effects. When tremolo is active, the tone is very full; you don't miss reverb. It would be nice to have at other times, though.

'58Bassman
04-18-2012, 07:44 PM
They're being shipped now. The tone is very straightforward, like you'd expect from a "1950s" amp. It's midrangey, but not honky. Bass response is somewhat restrained. I found the mic and accordion inputs to be mostly useless for guitar. Amps like the Blues Junior and Princeton Reverb have more tonal complexity, more harmonic content. I wouldn't call the Excelsior tone classic Fender. It's neither tweed nor blackface.

It gets pretty darn loud before it breaks up.

You get woman tone by rolling back the tone on your guitar, turning up the volume, and throwing the tone switch to "dark." The contrast between bright and dark is large. It cries for a middle position or a real tone control. Expect to see one as a mod.

The tremolo is deep and throbby. It goes nice and slow, but I wish it would go faster for shimmer effects. When tremolo is active, the tone is very full; you don't miss reverb. It would be nice to have at other times, though.

Well, if they're trying to depart from tradition, they seem to have done it pretty well. The amps it's "modeled after" were funky, weird, oddly constructed and I'm amazed by the number I have seen that never used any kind of tag or turret board. Soldering the parts right onto the tube sockets, switches and terminal strips looks like a disorganized mess in a lot of the ones I've seen. My Oahu looks more organized than some- at least it has a heavy wire that passes through the middle and attaches to the shell, used as a ground buss.

jadams71
04-18-2012, 07:46 PM
I am interested to see what more things this amp will be capable of in the hands of someone like Billm.

Billm
05-06-2012, 11:02 AM
I've had a little more bench time with the Excelsior. Mine now has a tone control. http://www.tdpri.com/forum/images/smilies/icon_smile.gif

It's strictly one-knob, tweed style, and uses the Excelsior's stock bright and dark as its upper and lower limits. Tone is very progressive through the range and the middle is bright, but well supported by the bass notes. Single-knob is the right way to go for this amp. A TMB stack steals too much power.

Installation is easy enough; the biggest challenge, as I mentioned above, is to replace the Bright/Dark switch in an aesthetically pleasing way. The control I'm using has a pull-up switch, which could conceivably be used as a full-on Raw control, but I haven't tried that yet.

I've also been experimenting with master volume controls to see if there's usable crunch tone at bedroom levels. I'm not real pleased with the tone. The correct answer for this amp may be "pedal." I've got more parts arriving next week; the experiments continue.

The 15-inch speaker, as you would suspect, contributes to the distinctive tone. But a Swamp Thang is noticeably louder and goes just as deep. It's rounder and smoother, too. I don't know anyone who has a stock of 15-inch speakers that I can test with, but clearly, different speakers will affect the tone of this amp strongly.

Fender has this thing biased hot -- it's idling at 12+ watts per tube. With cathode bias, there's not much you can do about that, other than change the cathode resistor. JJ 6V6s sound noticeably better. The bigger plates can handle the high idle dissipation better, too.

And of course, the TO20 output transformer gives it rounder, fuller tone.

The experiments continue.

Billm
05-06-2012, 06:51 PM
It turns out that raw tone, with no voicing, is painfully bright, not particularly useful except for maybe peeling paint. Not an option.

I also slightly overstated the hotness of the bias. It's running a shade under 12 watts per tube.

matchless
05-07-2012, 04:31 PM
this is how marshall should have made the 1 watt series-

JStizz
05-07-2012, 05:24 PM
so far, what are your recommended mods?

tone knob to replace the dark/bright switch? different tubes? both? others?

Nonvintage
05-16-2012, 05:30 PM
What 6V6's come with the amp and what are the preamp tubes? I haven't heard or have seen one but I like the idea of a single tone control rather than a hi lo switch.

Billm
06-02-2012, 09:10 AM
I shot a video with my single-knob tone control mod and before-and-after comparison of the Legend 1518 speaker.

The speaker really improves the tone quality while retaining vintage tone. I love it!

I'm pretty happy with the tone control, too. I'll be making some more circuit mods to the amp, but my goal is to preserve its essential, raw nature, not to make it sound like anything else.

http://billmaudio.com/wp/?page_id=1203

Although I did the testing with the stock tubes, I prefer JJ 6V6s. The larger plates give the amp a fuller, more open/effortless sound.

whaiyun
07-30-2012, 11:26 AM
Cool! I'd love to use the Excelsior as a mod-practice amp :D Keep working on it!

tcaron
07-30-2012, 11:33 AM
I've been gigging with this amp for the last three weeks. I did repalce the tubes with JJ 6v6s but I really didn't need to. I'm not convinced that I need the tone mod either.
I am able to tweek the tone with pedals on my board. All I need to do now is set the volume on the amp to around 10:00. I need a clean amp and this does it. My Zendrive delivers the OD for me, not the amp. I have a Carr Rambler and its been sitting in the basement the last three weeks.

I may replace the speaker with the 1518 but making the amp heavier may not be a good tradeoff.

All I can say is to get one or at least try it! Do not give up on it after a quick guitar store test. These are nice little amps. The 15" speaker is great.

Tom C

jimmyg
02-05-2013, 07:02 PM
is there a easy way to add a preamp bypass switch? would like the ability to use the amp clean at higher volumes
thanks

IM4Tone
02-05-2013, 07:39 PM
is there a easy way to add a preamp bypass switch? would like the ability to use the amp clean at higher volumes
thanks
Have you replaced the speaker w/ the Legend 1518? LOTS more clean volume at a sensitivity of 103.4 db!

Figaro
04-02-2013, 05:49 PM
I just discovered you can set the Excelsior's 2 way tone switch in the middle to get a 3rd tone sound. Give it a try! This is great because the dark setting is too dark and the bright setting is too bright. I would love to find a 3 way switch that would replace the 2 way for easy 3-tone adjustments.

SBax
04-02-2013, 06:02 PM
Didn't know you could do that. Sorta like running an old strat with the pickup in the in-between position.

I replaced the switch with the pot. Usually, it's at 11 o'clock. I also replace the knobs so all three match.

http://i182.photobucket.com/albums/x105/koptapad_2007/fd139fac39b8fca661c1a608a0a77b6e_zps6ba548ae.jpg


I also got some old alnico 15" speakers to try. Date code 1960.

http://i182.photobucket.com/albums/x105/koptapad_2007/3a19bdb57c4c07265ad7105c793584b0_zps50c528c9.jpg

IM4Tone
04-02-2013, 06:15 PM
I just discovered you can set the Excelsior's 2 way tone switch in the middle to get a 3rd tone sound. Give it a try! This is great because the dark setting is too dark and the bright setting is too bright. I would love to find a 3 way switch that would replace the 2 way for easy 3-tone adjustments.
If going to the trouble of replacing the switch, it's the same effort and very minimal cost to just put in a 500k ohm pot and get continuous variability. Very simple for even the least skilled person.

Figaro
04-02-2013, 06:40 PM
I've read that it's hard to find a pot with a small enough mounting that will fit through the switch opening without having to drill it out. A 3-way switch (if I could find one that fits the mounting screw holes) would be enough options for me along with my guitar's tone control, so try the middle setting and see if it works for you.

Figaro
04-02-2013, 06:42 PM
Did you have to make the switch opening larger to mount the tone pot?

Didn't know you could do that. Sorta like running an old strat with the pickup in the in-between position.

I replaced the switch with the pot. Usually, it's at 11 o'clock. I also replace the knobs so all three match.

http://i182.photobucket.com/albums/x105/koptapad_2007/fd139fac39b8fca661c1a608a0a77b6e_zps6ba548ae.jpg


I also got some old alnico 15" speakers to try. Date code 1960.

http://i182.photobucket.com/albums/x105/koptapad_2007/3a19bdb57c4c07265ad7105c793584b0_zps50c528c9.jpg

SBax
04-02-2013, 07:38 PM
Did you have to make the switch opening larger to mount the tone pot?

No. No drilling involved. Pretty sure it was a standard CTS pot.

IM4Tone
04-03-2013, 12:18 AM
No. No drilling involved. Pretty sure it was a standard CTS pot.
The slot must be widened ever so slightly with a small file (or Dremel tool) for the pot's threaded stem to go through. Don't make a big deal out of it. It's not brain surgery. It would be done in as much time as it took to write this!
It looks like this: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=023-580 Dia.=5/16". Just snip the tab that sticks up so it can mount to a flat under-surface.

Jon Silberman
04-03-2013, 07:02 AM
The amp is beginning to sound like the "Son of Blues Junior" - another Fender amp that misses the mark, requiring so many mods and component changes to sound decent you have to wonder why not just buy a better one from the start. But if I'm wrong, correct me, I have an open mind.

Prairie Dawg
04-03-2013, 07:27 AM
It's built to a price point. Installing a tone control and a vibrato foot switch takes less time to do than to tell about it. It's great for novice amp mechanics and hobbyists to cut their teeth on.

IM4Tone
04-03-2013, 07:53 AM
It's built to a price point. Installing a tone control and a vibrato foot switch takes less time to do than to tell about it. It's great for novice amp mechanics and hobbyists to cut their teeth on.
:agree 100%
And the speaker swap is optional and many don't consider a speaker swap a real 'mod.'
Of course, if you want an amp that you don't have to touch, just plug it in and play, it may not be for you.
BJ mods have gone viral and it's easy to get significant time and money tied up in the BJ. At least that's the conclusion I've come to when considering mod'ing my BJ. I elected not to do it, but the minor changes to the Excelsior are so easy an inexpensive, why not. BTW, first amp I ever modified.

SBax
04-03-2013, 07:33 PM
The amp is beginning to sound like the "Son of Blues Junior" - another Fender amp that misses the mark, requiring so many mods and component changes to sound decent you have to wonder why not just buy a better one from the start. But if I'm wrong, correct me, I have an open mind.

The whole Fender Pawn Shop idea of a fantasy amp is definitely a weird left-turn for a large company. The too-much-treble & too-much-bass switch is like a purposeful oddity. Just like the unbelievable speaker in the Pawn Shop Greta. It's a toy speaker that's so useless. I replaced it with a full range 4" speaker made for a PA and it sounds so much better.

Those two self-sabotage points are cute quirky things from a brainstorm session by R. Flieger or something. I get the joke. I actually kind of like it too but I can't explain that part.

As far as the speaker in the Excelsior, it's usable, a bit flubby just like what you would expect from a cheap 50s-60s amp. I want to try those alnicos because I put the 12" versions in a Silvertone 1484 cab and love it. Plus, there are cheap on ebay and under the radar.

Figaro
04-03-2013, 08:28 PM
I owned a Blues Jr and just never liked it, even after I did all the Billm mods to it. The mods did make it sound better but still not as good as other amps you can buy for about the same price + the cost of all the mods, like a used Princeton Reverb Reissue.

The Excelsior sounds great as-is and the only mod it may need is to replace the Dark/Bright tone switch. Replacing the speaker and tubes is not a mod. The stock speaker sounds ok but some people will replace it for a more efficient one, to get a different tone, etc... The stock tubes are cheap and definitely need to be replaced. It's the best all tube Fender style amp you can buy for $299 new.

thosk
04-03-2013, 09:01 PM
I found the tone switch and speaker to be much more usable after a good break in.
A cheapo Dano Fish & Chips EQ pedal also works well.
That being said, I installed a tone pot and Legend 1518 anyway-just 'cause I like to tinker. The down side is it is now much heavier....

IM4Tone
04-03-2013, 10:46 PM
..............That being said, I installed a tone pot and Legend 1518 anyway-just 'cause I like to tinker. The down side is it is now much heavier....
I couldn't believe just how much heavier! Mine is now 42-43# whereas stock is (I think) 36#! :omg That's a lot for a 13 watt amp, but then, there's a lot more volume there besides the improved tone.

Jon Silberman
04-04-2013, 06:03 AM
This is kinda what I meant by maybe buying the amp you really need from the outset might be a better strategy.

guitarzam01
04-04-2013, 07:36 AM
PRAIRE DAWG
did u put the vibrato foot switch on ur's, I was going to but held off because billm
had said he didn't know if it would change how it worked because of long cable,
if u did, did it make diff, I have a foot switch that I bought for this, but been waiting
for more info on it,, I did the tone control and tube change, also moved the speaker
jack so it is easy to get at so I can plug my 2x12 cab into it, I put a JBL2225h bass
speaker in mine and love the tone

thanks for any help u can give me on this

Chuck

Eveready
04-04-2013, 08:04 AM
The whole Fender Pawn Shop idea of a fantasy amp is definitely a weird left-turn for a large company. The too-much-treble & too-much-bass switch is like a purposeful oddity. Just like the unbelievable speaker in the Pawn Shop Greta. It's a toy speaker that's so useless. I replaced it with a full range 4" speaker made for a PA and it sounds so much better.

Those two self-sabotage points are cute quirky things from a brainstorm session by R. Flieger or something. I get the joke. I actually kind of like it too but I can't explain that part.

As far as the speaker in the Excelsior, it's usable, a bit flubby just like what you would expect from a cheap 50s-60s amp. I want to try those alnicos because I put the 12" versions in a Silvertone 1484 cab and love it. Plus, there are cheap on ebay and under the radar.


I have a Greta and would like to find a replacement speaker for mine. What did you put in yours and where did you get it?

Cheers!

SBax
04-04-2013, 06:13 PM
http://www.ebay.com/itm/4-Square-Speaker-8-Ohms-5W-Good-Replacement-for-the-All-American-Five-New-/300879629904?pt=Vintage_Electronics_R2&hash=item460dd2ce50

Oops. It's actually a radio speaker. Here's what I was supposed to get.

http://i182.photobucket.com/albums/x105/koptapad_2007/058bc297258c3f3198ad269e0757d3a9_zps712ddf20.jpg


http://www.fullcompass.com/brand/QUM.html

There three 4 inch Quam speakers here. Probably better than the Taiwan-made speaker I bought. I would suggest the Quam speaker. I will get one of these too and compare.

You can get the data sheet for the Quam speaker to check the speaker depth. 2 inch max depth for the Greta.

Kevbo599
04-04-2013, 06:26 PM
Thanks SBax!

IM4Tone
04-04-2013, 07:05 PM
This is kinda what I meant by maybe buying the amp you really need from the outset might be a better strategy.
I don't know of any other currently mfg. amp that has this same sound, so I see no alternative. Besides, I don't need this amp at all, I wanted it, and wanted to "tinker". Turned out far beyond my expectations. I got it new for a steal @ $239; <$10 for the tone pot mod; and $90 for the Eminence. Getting the 15" Eminence was an experiment on it's own as I never had an amp w/ a 15" speaker. Another success. If I ever care to sell the Excelsior, I'll put the orig. spkr. back in and re-use the Emi Lgnd elsewhere.
If you don't understand this, you don't know tinkeritis!;)

jimmyc
06-08-2013, 09:01 AM
I couldn't believe just how much heavier! Mine is now 42-43# whereas stock is (I think) 36#! :omg That's a lot for a 13 watt amp, but then, there's a lot more volume there besides the improved tone.

I'll bet the style-ized MDF cabinet is responsible for a good chunk of the weight. At this price point I wouldn't expect a real wood cabinet but I'm willing to bet that if one were to mount the chassis & speaker into a typical tweed-style pine cabinet the weight would come down quickly, and the tone would improve too.

I'm thinking of mounting my Excelsior in a Pine cab, the question then is do I stay with the 15" or go to 12" speaker and waaaaaay more speaker choices...

IM4Tone
06-08-2013, 01:27 PM
I'll bet the style-ized MDF cabinet is responsible for a good chunk of the weight. At this price point I wouldn't expect a real wood cabinet but I'm willing to bet that if one were to mount the chassis & speaker into a typical tweed-style pine cabinet the weight would come down quickly, and the tone would improve too.

I'm thinking of mounting my Excelsior in a Pine cab, the question then is do I stay with the 15" or go to 12" speaker and waaaaaay more speaker choices...
The cab may account for a 'good chunk' of the 36#, but the increase of 6# (to 42#) was due to the Legend 1518 with a huge magnet!

A pine cab would be nice and for my taste, I'd stick with the 15" Legend. You don't need a large selection if there are a couple good ones that suit the amp.

Billm
09-06-2013, 06:39 PM
I modded my Excelsior for faster tremolo. There were some songs that just didn't "play right" when you incorporate the tremolo beat into the tempo. It's an easy mod if you do it quick and dirty, and not much more difficult if you do it "right."

The speed pot is bounded by two 100K resistors, R21 and R37. If you make these resistors smaller, it will increase the maximum tremolo speed without affecting the minimum speed. You can do an easy top-of-board mod by soldering another 100K resistor across the leads of R21 and R37. Two 100K resistors in parallel gives you 50K, and lets the circuit oscillate faster.

The maximum speed, according to my meter, goes from 5.3Hz to 6.4Hz. That doesn’t sound like a lot, but it’s a 20 percent increase. Using 82K resistors (effectively 45K) only gets you to 6.5Hz. I have 82K resistors soldered into mine, and I’ll probably leave it that way.

Note that if you go too low or try to run without resistors, the tremolo circuit may not oscillate. It’s fussy.

http://billmaudio.com/wp/wp-content/uploads/2013/09/tremolo-mod.jpg

Figaro
09-07-2013, 09:48 AM
BillM, Do you have your tone control mod for the Excelsior available for sale yet?

Billm
09-07-2013, 10:13 AM
I have a new version of it installed in my amp, but it's too woofy. I need to use a smaller cap. Working on it when I can fit it between all the Blues Juniors.

Billm
09-07-2013, 08:20 PM
OK, I whipped up a different version of the control. Less woofy when you turn it all the way down, but it feels kind of midrangey. If I get a chance tomorrow, I'll record both and put 'em out there for comment. It has a pull-up bypass, so you get the raw tone of the amp. Gotta say, the raw tone is pretty midrangey, too.

These experiments certainly show the limitations of a single-knob control and only two gain stages. There's no opportunity to re-amplify the losses your get from a two- or three-knob tone stack. Then again, the Excelsior was designed to be a funky amp, and it remains a funky amp pretty much no matter what you do to it.

Billm
09-08-2013, 09:21 PM
... and here's a link to a page that has the original video, plus two versions of the new tone control.

http://billmaudio.com/wp/?page_id=1506

Figaro
09-08-2013, 09:40 PM
I prefer the 2nd version. It's more effective both ways. I assume the 2nd version can get all the tones of the 1st version and more?

guitarrhinoceros
09-08-2013, 09:55 PM
I modded my Excelsior for faster tremolo. There were some songs that just didn't "play right" when you incorporate the tremolo beat into the tempo. It's an easy mod if you do it quick and dirty, and not much more difficult if you do it "right."

The speed pot is bounded by two 100K resistors, R21 and R37. If you make these resistors smaller, it will increase the maximum tremolo speed without affecting the minimum speed. You can do an easy top-of-board mod by soldering another 100K resistor across the leads of R21 and R37. Two 100K resistors in parallel gives you 50K, and lets the circuit oscillate faster.

The maximum speed, according to my meter, goes from 5.3Hz to 6.4Hz. That doesnít sound like a lot, but itís a 20 percent increase. Using 82K resistors (effectively 45K) only gets you to 6.5Hz. I have 82K resistors soldered into mine, and Iíll probably leave it that way.

Note that if you go too low or try to run without resistors, the tremolo circuit may not oscillate. Itís fussy.

http://billmaudio.com/wp/wp-content/uploads/2013/09/tremolo-mod.jpg

Wow.

Stonebandit
09-09-2013, 12:09 AM
Nice work there Billm.
I may well have to repurchase the Fender Excelsior. I think with the mods and a tube change, it would be close to a prefect vintage sound.

IM4Tone
09-09-2013, 05:57 AM
I too prefer the 2nd version. However, depending on the complexity of installation and cost, I don't see enough difference vs. the original 'pot replacing switch mod.' to necessarily want to do it. If I were starting with a new stock amp, probably would want version 2.

Billm
09-09-2013, 09:50 AM
This morning I tried changing the coupling caps that drive the 6V6s from the phase inverter. The stock caps are .01uF, and I've never seen a value that small driving 6V6s. I kludged in some .1uF Orange Drops and recorded it both ways. Unfortunately, the camcorder mic totally misses the change in tone. It's not earthshaking, just a little deeper, a little more articulate. When you get to distortion level, the larger caps drive the 6V6s a little harder and the breakup sounds nicer to my ear.

THiwaTT
09-09-2013, 03:47 PM
Not to derail the thread too much - Billm any plans for a Fender Greta Mod?
I have one that I adore and would love to see what you can do with one

Billm
09-09-2013, 04:11 PM
I've never seen and never played a Greta. It doesn't seem to have grabbed people the way the Excelsior has.

Billm
10-09-2013, 11:21 AM
I finally came up with a tone control that sounds good and is easy to install. Nothing to clip, just two joints to solder. Pulling up on the control bypasses it completely and gives you the amp's raw tone.

The brown vintage-style Fender knob works for me; the difference in color isn't as great as it seems here:

http://billmaudio.com/wp/wp-content/uploads/2013/10/panel-with-tone1.jpg

As you can see, you can turn the upper chassis around and mount it, so the amp is easy to work on when modding. That Orange Drop peeking out is an experimental larger coupling cap from the phase inverter. It didn't make much difference.

i8guitar
10-09-2013, 11:54 AM
Thanks for posting that Billm. I've been thinking about that tone control mod, but have been ok with setting the setting the switch halfway between bright and dark, using the stock speaker. We'll see if installing the Weber Vintage Chicago 15" will change my mind.

blake480
11-04-2013, 02:10 PM
I finally came up with a tone control that sounds good and is easy to install. Nothing to clip, just two joints to solder. Pulling up on the control bypasses it completely and gives you the amp's raw tone.

The brown vintage-style Fender knob works for me; the difference in color isn't as great as it seems here:

http://billmaudio.com/wp/wp-content/uploads/2013/10/panel-with-tone1.jpg

As you can see, you can turn the upper chassis around and mount it, so the amp is easy to work on when modding. That Orange Drop peeking out is an experimental larger coupling cap from the phase inverter. It didn't make much difference.

Just installed this mod yesterday on my amp. IT IS A MUST HAVE. Totally take the Excelsior to the next level. Especially with the pull up and raw tone. Seriously love it. Worth every penny.