Is my amp hand wired or PCB?

David Garner

Platinum Supporting Member
Messages
7,495
PCB's are completely serviceable, sure. But in some cases, they are much more labor intensive, such as in replacing a single bad pot on a DRRI where you have to unwrench each pot from the chassis in order to desolder one from the common pot PCB.

And then you have the whole issue with the smaller, flimsy pots used to mount on said PCB.

If I had a DRRI, I would continue to use its main PCB, but I would hand wire the pots and front panel input jacks back to the main PCB. Funny how the rear speaker jack, which for the most part ststaststays plugged in, gets a good quality, chassis mounted jack.


Personally, I wouldn't do a thing to it unless something failed. Really, most of us just aren't even turning the knobs on them all that much. Even those of us who gig.

Touring musicians might need a more robust construction, but they make their living with these tools. I have yet to have a PCB or hand wired amp fail, at home or on the road. I've had tubes fail. I had to buy a new nut for the input jack on my AC30. But nothing that wouldn't get me through a gig.
 

Guitar Dave T

Member
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11,653
Personally, I wouldn't do a thing to it unless something failed. Really, most of us just aren't even turning the knobs on them all that much. Even those of us who gig.

Touring musicians might need a more robust construction, but they make their living with these tools. I have yet to have a PCB or hand wired amp fail, at home or on the road. I've had tubes fail. I had to buy a new nut for the input jack on my AC30. But nothing that wouldn't get me through a gig.

You've been lucky. I've had pots and jacks go out on PCB amps, ON THE GIG.

BTW disuse is a bigger factor in pot failure. Now that Covid has me sidelined, I've had two pots go bad to where tuner cleaner won't fix the drop spots on two of my regular gigging amps. Fortunately they're both hand wired amps and it took more time to pull the chassis than to drop in and wire up the new pots.

I've really gotta start gigging again.
 

Todd1357

Member
Messages
304
Don't disagree with what you are saying, in general.

However, regarding price, we are talking about the two amps being compared in that video, not the entire universe of PCB and hand wired amps. In other words, it's a restricted population of samples/products being discussed in the video.

Don't disagree about mods in general - but, again, they are talking in the video about someone buying that specific HW Princeton model and doing mods to it. I don't think they were referring to Jim Marshall and Co. taking a Tweed Bassman and tweaking in order to accept EL34s -- because 6L6s and their variants were not available in the UK. Nor were they talking about icons in the amp industry like Smith or Dumble doing their thing. They are discussing the "everyday" player walking into their store, buying the HW Princeton in that video and doing mods.

Lastly, I don't think any player is "stuck with what is commercially available." There is a ton of amp builders out there, building numerous (i.e., tons of) flavors of amp circuits. It's a great time to be a guitar player/gear buyer; there have never been this many choices of amps, guitars, effects, etc. - and many at affordable prices. Conversely, I grew up when there were Fender, Marshall, Vox and Ampeg amps. And there were these two fairly new companies - Mesa Boogie and Peavey. Those were the choices.

Regarding your Fenders - rock on. Great amps, and they each have their place in a player's arsenal. :)

Good call, the video was more specific and I was talking general terms.

Rock on good sir! :dude
 

aeolian

Member
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6,471
Good info but you come across a bit condescending which kinda dilutes your message. Appreciate your experience and wisdom though. Would the change in the metallurgic structure affect conductivity at any level that would be perceptible? Or, is it more about making the connection weaker and more brittle?
I don't mean to be condescending but if you just say that PCB amps are serviceable all kinds of self proclaimed internet experts will contradict you. I hate the term expert, but here in Silicon Valley I am generally regarded as one of the experts in this area.
As to your question. There is a body of thought that the more granular solder joints exhibit a diode effect slightly rectifying the signal. This is a concern on high frequency RF like 5G cell phones. Whether the effect is audible in a guitar amp is debatable. I happen to think that it is audible in full range audio in artifacts like stereo imaging, but I'm not sure it affects guitars.
 

aeolian

Member
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6,471
Man, there are so many "straw man" and "fallacy" arguments these guys are making.
Agreed. The shop guy readily admits that the components are different. Given production tolerances you could probably take any three examples of either the hardwired or PCB amp and they would all sound different.
I've played Pre-CBS Vibroluxes that were soft and spongy, breaking up at 3 and others that were drier and stiffer than the typical Twin. Couple of different folks I know that have real extreme examples of variance. But more typically there's still audible differences between amps of the same model.
 

james evans

Member
Messages
153
hand wiring has it's issues as well...i have a '66 Supro Royal Reverb I have owned since 1971. When i finally had it serviced for the first time in the early 2000's, my Supro tech, Terry, found a wire that had been wrapped around a post but never soldered. 40 years on and just hanging there. it's soldered now
 

TonePilot

Member
Messages
5,611
I don't mean to be condescending but if you just say that PCB amps are serviceable all kinds of self proclaimed internet experts will contradict you. I hate the term expert, but here in Silicon Valley I am generally regarded as one of the experts in this area.
As to your question. There is a body of thought that the more granular solder joints exhibit a diode effect slightly rectifying the signal. This is a concern on high frequency RF like 5G cell phones. Whether the effect is audible in a guitar amp is debatable. I happen to think that it is audible in full range audio in artifacts like stereo imaging, but I'm not sure it affects guitars.
Thanks, probably not a factor in a guitar amp but perhaps if there's more than a few solder joints like that, they could add up to a negligible but discernible impact on sound.
 

doublescale1

Suhr S-Classic, V60LP's, Soft V neck
Gold Supporting Member
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7,279
FA-18's are PCB construction, they pull more G's than your DRRI or any other PCB built amp.
 

aeolian

Member
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6,471
FA-18's are PCB construction, they pull more G's than your DRRI or any other PCB built amp.
I was the manufacturing engineer for the heads up display in those (and the A10, AH-1S, F15, F117 and Israeli F4 upgrade). We did all kinds of violence to them to verify reliability. When the E/F upgrade was developed I did a ton of thermal cycle testing on the solder joints. Some of what I found got put into the Mil-Std-2000 workmanship standard. Like I've said many times, I've yet to see a gut shot of a boutique hardwired amp that would pass inspection to that standard even though it could have just as easily been done right. The information is right there in the public domain. After visiting his shop to have the panel changed on my amp and having a conversation about this with Tim Marcus I sent him a copy of the spec. He's using turrets correctly instead of the eyelet boards in Fenders, which are horrible. But he was interested in what more he could do to improve his product. Why major manufacturers can't get this right mystifies me.
 

coltonius

Señor Member
Silver Supporting Member
Messages
14,279
I was the manufacturing engineer for the heads up display in those (and the A10, AH-1S, F15, F117 and Israeli F4 upgrade). We did all kinds of violence to them to verify reliability. When the E/F upgrade was developed I did a ton of thermal cycle testing on the solder joints. Some of what I found got put into the Mil-Std-2000 workmanship standard. Like I've said many times, I've yet to see a gut shot of a boutique hardwired amp that would pass inspection to that standard even though it could have just as easily been done right. The information is right there in the public domain. After visiting his shop to have the panel changed on my amp and having a conversation about this with Tim Marcus I sent him a copy of the spec. He's using turrets correctly instead of the eyelet boards in Fenders, which are horrible. But he was interested in what more he could do to improve his product. Why major manufacturers can't get this right mystifies me.
I mean, congrats and all. I'm admittedly "not an expert" when it comes to these things but it seems you're comparing apples and oranges here. Peoples lives don't depend on whether an amplifier turns on or off one night- this is quite different from the military level stuff and even safety/ communications devices you've listed as an example.

I don't know your personal situation, but Fender seems to be doing pretty good for themselves and their methods of construction through the years. Sure, there are a few black marks on the QC board (later SF-era amps, the Hot Rod series)- but the majority of their designs are time tested and reliable enough for rock and roll. What you're doing is blaming a fish for its inability to climb a tree when it was never meant to do that in the first place.
 

jnovac1

Silver Supporting Member
Messages
8,102
I was the manufacturing engineer for the heads up display in those (and the A10, AH-1S, F15, F117 and Israeli F4 upgrade). We did all kinds of violence to them to verify reliability. When the E/F upgrade was developed I did a ton of thermal cycle testing on the solder joints. Some of what I found got put into the Mil-Std-2000 workmanship standard. Like I've said many times, I've yet to see a gut shot of a boutique hardwired amp that would pass inspection to that standard even though it could have just as easily been done right. The information is right there in the public domain. After visiting his shop to have the panel changed on my amp and having a conversation about this with Tim Marcus I sent him a copy of the spec. He's using turrets correctly instead of the eyelet boards in Fenders, which are horrible. But he was interested in what more he could do to improve his product. Why major manufacturers can't get this right mystifies me.
mark bartel is doing good work.
 

aeolian

Member
Messages
6,471
All I'm saying is that doing things correctly doesn't really change things. I currently work in consumer products and completely understand cost effective manufacturing. My current title is Design For Manufacturing Engineer. How to make small adjustments to the design of a product so that it can be made more cost effectively and reliably. The tube amplifier world is caught up in tradition. And some other idiotic ideas about "craftsmanship" that has wiring routed to look like it was done with great care but actually puts strain on the terminations.
One constant in these discussions seems to be the need to be repaired on the road by any local tech. The obvious question is why did it need repair? So doing things correctly so that it is reliable would seem to be worth some effort.
 

HotBluePlates

Member
Messages
14,069
... There is an unquestionable advantage to handwired construction, and that is ease of repairs and modifications, and it's fine to prefer it for that reason.
Please, for the love of all that is tone would people stop repeating this stupid myth. In this day and age, if someone don't know how to desolder a component from a circuit board without wrecking it I don't want to let any of my gear near them.
I'm an electronics manufacturing engineer of some 40+ years experience. ... people complain about a PCB Deluxe Reverb?

It's not a matter that "p.c. boards cannot be repaired" (I suspect many who re-state the argument in this fashion have never repaired either a p.c. board or a handwired amp). The simple fact is the time/effort burden is shifted from the manufacture of the item to the repair of the item.

Pots

- As long as the hand-wiring builder doesn't make the silly choice of a "pot ground buss" then replacing a pot (in a vintage Marshall/Fender/Vox/etc style amp) is as simple as removing the one pot, desoldering a few wires, and installing the new pot.​
- Most p.c. board amps use board-mounted pots (sometimes including the input jacks & other switches on that board). Now everything on the front panel has to be dismantled to access & remove/replace the single pot. This is more time for the repairman, so more $$ charged to the customer.​
- Sometimes the engineer devising the fitment of the boards got too clever packing things in a small space. Removing the board holding front panel controls also requires removing other boards/assemblies to make room for the pot board to move backwards into the chassis to drop the pot-shafts back through the chassis holes.​
- When the amp itself has a low retail price, the labor-time for the repairman to go through these extra steps makes repair un-economical. I actually talked with a repairman in this situation, who was repairing an amp with a sheared-off knob/pot-shaft. The labor time for complete disassembly of the amp would result in a charge higher than the buying the amp on the used market. He had to tell the customer it was in his best interest to trash the amp rather than repair it.​
Board Components

- Same deal here: the burden is extra time. A turret board or eyelet board allows easy desoldering/removal of a single part from the top-side facing the tech when the chassis is accessed. The new part can generally be easily installed without needing to mess with anything else.​
- P.C. boards most often (though not always) have the part loaded from the top and the solder pads on the underside. So the entire board has to be un-mounted from the chassis to access the solder joint, with a time burden. There are usually wires running from the board to tube sockets that are soldered on both ends, requiring lots of wiring to be desoldering from the tube sockets. Desolder the part, install the new part, but now re-wire the board to the tube sockets. Lots of extra time, so more $$$ for the customer to pay.​
- P.C. board amps often have (inexplicably) quick-connect wiring for things that don't get desoldered often. Fender is well known for making connections to the power cord, power/standby switches, fuse holder, power transformer to board, and similar connections this way. Faster for them to assemble, but more questionable over time whether those connections hold up compared to a soldered connection. And they're not a time-saver for the tech, especially if they need to prep & add quick-connects to a replacement power transformer's wiring.​
Ask any repairman what they'd rather service, and they'll almost always choose a handwired amp (unless the original workmanship was bad). And the repair bill winds up being smaller for their customer, because less time was taken to perform the repair.

____________________________________

It's not really fair to bring up military electronics, as that's a whole other world. The time/cost to repair is not really a factor (even on a Navy ship), because there's an "organizational" level of maintenance that will "fix a malfunction" by pulling a box out of a plane and installing another box (akin to saying, "Your amp is broken? Here's a new amp.")

The "broken box" gets shuffled off to a different ("intermediate") level of repair, that attempts to troubleshoot & repair it to the component level. If they can't, or the amount of damage is beyond local skill/capability, they send it off to yet another ("depot") level of repair.

They don't fixate on cost to the degree the average guitar player does. Whether it's swapping a transmission on a HMMWV, replacing a wing due to fatigued metal on a plane, or custom-making avionics wiring harnesses, the military has spent the money and established a maintenance structure that minimizes the burden on the end-user.

... Inside your cell phone there are terminations the size of a hair. ...

Ever repair a cell phone with a cracked screen? I did (cause my ex was a klutz). It required removing the back cover & disassembling every element of the phone because the only way to get to the screen was from the back. Then install the new OLED display & rebuild the phone front-to-back. I only bothered with it once (though I did save some money over paying the repair bill involved after "insurance"), but if it happens in the future I'd just toss the phone in the trash and get a new one.

... The Peavey Classic 30 had three boards that were initially made in one piece with some slots where they would separate. ... After wave soldering ... the boards ... were snapped and the assembly folded in thirds. Extremely clever. ... It did mean a bit more disassembly to get at some parts, but was an extremely clever packaging and a cost effective manufacturing solution for a low cost amp.

Thanks for making the point for me. :rotflmao These things are great for the manufacturer and horrible for the repairman. Your friend's board hides all the solder joints inside a little box.

-OXv3fZmu0VOpJgxtewZaGc9qcIPTPRGDSPGYmiAjw3rXr_63qXfV6ulVrnQ3QaEcAAxWqkBxv16YLkV7L0EDGJyN0dYCxHUzzepLzBGxXEaFUVLFHxyeCc9

Now I'm not saying the average guitar player is even right in their opinions of various construction styles. More often, I see folks who've been swayed by what the Marketing Dept has sold them as "Features." But most manufacturers appear driven by the players' demand for cheaper amps, and have gone to great lengths to economize the manufacturing processes to meet that demand.

But the same effort doesn't appear to be expended on increasing the serviceability of those amps. And at a labor rate of $75-100/hour, it's very easy for low price-point amps to become disposable rather than repairable.
 
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InkStained

Member
Messages
4,180
These are great amps. I’d leave it as is.

OP, I’m guessing that had you not ever come to this site or any like it, you’d be thrilled with the amp and not care one bit how the innards are constructed. That goes for you, me and a whole bunch of others.

These reissues have been around for like 30 years now. They are workhorse amps. Fender got with the times when they designed them. Marshall amps have been PCB since the mid 70’s

Great post. Every line is true.

The PCBs "reissues" have been around much longer than the handwired originals by this point. They really don't need to "prove" anything to anyone.
 

TonePilot

Member
Messages
5,611
All I'm saying is that doing things correctly doesn't really change things. I currently work in consumer products and completely understand cost effective manufacturing. My current title is Design For Manufacturing Engineer. How to make small adjustments to the design of a product so that it can be made more cost effectively and reliably. The tube amplifier world is caught up in tradition. And some other idiotic ideas about "craftsmanship" that has wiring routed to look like it was done with great care but actually puts strain on the terminations.
One constant in these discussions seems to be the need to be repaired on the road by any local tech. The obvious question is why did it need repair? So doing things correctly so that it is reliable would seem to be worth some effort.
What would the additional cost be to ensure no failures occur?
 

JPH118

Silver Supporting Member
Messages
4,780
hand wiring has it's issues as well...i have a '66 Supro Royal Reverb I have owned since 1971. When i finally had it serviced for the first time in the early 2000's, my Supro tech, Terry, found a wire that had been wrapped around a post but never soldered. 40 years on and just hanging there. it's soldered now

not uncommon amongst old amps! it always makes me laugh, but more importantly, shows that they took the time to make a mechanical connection which stayed in place for 30+ years, even if they forgot to solder it, haha.


Regarding PCB vs handwired, the biggest issue I have are the cheaper components they squeeze into PCBs, and sometimes WHERE they squeeze them regarding heat... although Fender is known to cheap out a bit on their handwired stuff, too. That, and something as simple as reflowing a cold solder joint can be murder on some PCB designs.
 
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JPH118

Silver Supporting Member
Messages
4,780
The Peavey Classic 30 had three boards that were initially made in one piece with some slots where they would separate. Bus wires connecting one board to another were stuffed using an auto insertion machine along with the other axial components. After wave soldering the small webs holding the boards together were snapped and the assembly folded in thirds. Extremely clever. I worked with the manufacturing engineer who dialed this process in. It did mean a bit more disassembly to get at some parts, but was an extremely clever packaging and a cost effective manufacturing solution for a low cost amp.

and when I get one in the shop, I’m charging double over an original human-wired ‘65 Deluxe for all the reasons you just detailed. It might be clever from a design standpoint, but when the repair bill exceeds the value of the amp, it ceases to be efficient and immediately becomes an expensive doorstop.

those Peavey Classic amps don’t sound bad, but they’re not exactly Modern Marvels or anything. Replacing those ribbon connectors when (not if) they break is a real joie de vie.
 
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newlongevity

Member
Messages
27
Setting aside what sounds better (which comes down to taste/bias), what is technically easier to work on (probably depends somewhat on the specific person's expertise/passion, right?), or what is more reliable (depends on how well it's maintained and cared for) no one brings up the point that vintage amps are great because they are a piece of history. Just like old cars, old bicycles, old houses, they can be temperamental, expensive to maintain, generally kind of a pain, but having/playing through something that was made in some extinct London factory 50 years ago that basically laid the blueprint for all amps today is an amazing feeling. It's that simple. Owning and caring for antiques is fun. Its electronics recycling in its highest form. If that doesn't blow your hair back, there is probably no reason not to just buy a new amp and not worry about any of it. A lot of amp techs love to work on old amps. Their shops are full of things that may never work again, but man, many times they do, and that's awesome. I love bringing my amps in their and letting them talk my ear off about the details. It's a noble profession/hobby. Respect!
 

amper

Member
Messages
1,988
Short of pulling the chassis, was wondering if any of you guru's know the answer. Was told it was hand-wired but not sure anymore.

It's a 1965 Fender Deluxe Reverb Re-issue I purchased new in 2016.

View attachment 268464
Not handwired, unless someone gutted it and converted it.

Only the Fender models named “Custom” are handwired, and the ‘65 DRRI isn’t one of them. The ‘64 Custom Deluxe Reverb is.

Also, the apostrophe matters. Fender very specifically calls the ‘65 Deluxe Reverb the “‘65” and not the “1965”, to avoid confusion with actual 1965 Deluxe Reverbs (as in, made in 1965, not 2016).

Whenever you see an apostrophe, it’s a reissue, and should always be refers to using the apostrophe, so you don’t get accused of falsifying the vintage of your amp.
 




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