PCB amps vs. PTP hand wired?

rspst14

rspst14

Tone Cat
Hey guys, I have some experience with working on PCB amps, but I've never had the chance to open up a point-to-point hand wired amp. I came across an old Bassman head at a good price, but it needs a bit of work. Nothing major, and I'm confident I can do it myself. I guess this question is aimed at guys like Lew and Scott, as well as the amp techs that visit the forum...first of all, is it easier or harder to work with these types of amps, compard to PCB amps? Second, is there any advantage to this type of design? Other than it's appeal on the vintage market, is there any benefit to having an amp that uses PTP wiring in favor of circuit boards? Any help would be appreciated. Thanks.

Ryan
 
Re: PCB amps vs. PTP hand wired?

rspst14 said:
Hey guys, I have some experience with working on PCB amps, but I've never had the chance to open up a point-to-point hand wired amp. I came across an old Bassman head at a good price, but it needs a bit of work. Nothing major, and I'm confident I can do it myself. I guess this question is aimed at guys like Lew and Scott, as well as the amp techs that visit the forum...first of all, is it easier or harder to work with these types of amps, compard to PCB amps? Second, is there any advantage to this type of design? Other than it's appeal on the vintage market, is there any benefit to having an amp that uses PTP wiring in favor of circuit boards? Any help would be appreciated. Thanks.

Ryan
Click to expand...

I also mod amps and have worked on an A/Bd both the ptp and the pcb...The PTP is in fact quicker and easier to work on...It's biggest con,is stray antenna like effects from long wire and crossing wire runs and humidity...The PCB is for the most part,free of these problems...I've A/Bd my PCB 73 Marshall 50 watt head to a PTP head of the same year and there's no audible difference other than component tolerences at best..I Like the looks of the PTP inside and it's ease of fixing and tweaking,but tonewise,both are fine..

My 73 50 watt "Plexi" spec'd head sounds ungodly and you'd never know it was a PCB Marshall...Lots have been done inside of it including an output transformer upgrade and many other cool things,but still....

John
 
Last edited:
Re: PCB amps vs. PTP hand wired?

They're a lot easier to work on, since you don't have to unscrew PCB layers and track a problem down to a tiny component. The components normally sound better because they're big high wattage ones. As far as the sound, the simpler and bigger the tracers are between components, the better. That's why John's 73 Marshall sounds the same as a 71. Marshall changed from P to P in the middle of 73, but the PCB's in the 70's were laid out almost the same as they would be in a P to P amp. It wasn't till the 80's that the PCB's became cheap, complicated, and had tiny resistors.
Then, in the 90's, they started using cheaper transformers. That's why people say "they don't build them like they used to."

Does anybody know when Fender went from P to P to PCB? I've always thought it was in the mid 70's.
 
Re: PCB amps vs. PTP hand wired?

Yes....they are alot easier to work on. Much easier to unsolder old parts and solder new parts in. Or to do tone tweaks and parts substitutions. I think they have the PCB pretty well figured out these days to where they sound really good and have overcome some of the problems they had in the beginning. But I don't own a single PCB amp and the reason I wound up buying the Matchless SC 30 was that it was so beautifully handwired and the reissue AC 30 I'd thought about buying is not.
 
Re: PCB amps vs. PTP hand wired?

They sound better because there is more metal between components creating less resistance and also in theory is better for the high's since it is believed they travel on outmost portion of the metal. Gearjoneser is right on about them being easier.
 
Re: PCB amps vs. PTP hand wired?

I don't like pcbs at all. First, because some of them are nearly impossible to repair, and second, because of the insane layouts required for the 2 and 3 channel switchers cause all manner of uncool and unintentional signal coupling across the boards which, in turn, requires all manner of desparate and inelegant measures to prevent the amp from turning into an r.f. continuous wave transmitter. Thats why a lot of amps from '80s to present have the magical ability to sound harsh and dull at the same time.

The simple layouts for the early seventies plexi circuit Marshalls are excellent and those amps, in good repair, sound as if The Lord Has Returned. The pcb doesn't necessarily affect the tone, the layout does.
 
Re: PCB amps vs. PTP hand wired?

This is one of those odd things where, I guess, it depends a lot on what you're accustomed to. I much prefer PCB's to PTP. But then again, all my experience, and soldering equipment is geared for PCB.

I hate working on PTP. ;)
 
Re: PCB amps vs. PTP hand wired?

ArtieToo said:
This is one of those odd things where, I guess, it depends a lot on what you're accustomed to. I much prefer PCB's to PTP. But then again, all my experience, and soldering equipment is geared for PCB.

I hate working on PTP. ;)
Click to expand...

On my 73 Marshall PCB,I took the entire board out,did all the changes I wanted and put it back in...The board in my 73 is almost identical to the later JCM 800 boards....No one seems to dog the 800 series and these were "all" PCB...I Like PTP for the ease of working on it,but if the amp has "Tone" I could care less either way really...The components make more of a difference than the board itself(I say anyway?)

John
 
Re: PCB amps vs. PTP hand wired?

ArtieToo said:
This is one of those odd things where, I guess, it depends a lot on what you're accustomed to. I much prefer PCB's to PTP. But then again, all my experience, and soldering equipment is geared for PCB.

I hate working on PTP. ;)
Click to expand...

Just so's everyone knows:

PCB = printed circuit board
PTP = point to point...NO CIRCUIT BOARD. The parts are all wired ppoint to point.
HWCB = handwired circuit board like you see in old Marshalls and Fenders from 60's and 70's.

I just made up the HWCB designation! :laugh2: I don't know what it's called, but that's what I call it and what I mean when I say an amp is handwired.
 
Re: PCB amps vs. PTP hand wired?

Lewguitar said:
Just so's everyone knows:

PCB = printed circuit board
PTP = point to point...NO CIRCUIT BOARD. The parts are all wired ppoint to point.
HWCB = handwired circuit board like you see in old Marshalls and Fenders from 60's and 70's.

I just made up the HWCB designation! :laugh2: I don't know what it's called, but that's what I call it and what I mean when I say an amp is handwired.
Click to expand...

Good info Lew....I always put all amps wired from component to component as Point To Point wired....Most of the early PCB amps had the solder end of the components on the bottom of the board...Some later amps had the solder ends at the top with the copper board tracings facing upwards,like Mesa,Soldano....
 
Re: PCB amps vs. PTP hand wired?

btw - did anyone else read that article from Bogner, that Stratcat linked to? Apparently, that guy didn't have great things to say about Orange Drop caps.
 
Re: PCB amps vs. PTP hand wired?

It seems to me like PTP are more durable, without the fragile circuit board to break or otherwise get screwed up. If something goes wrong in a PTP just unsolder and replace the bad part. All the classic amps are built like that, and so many of them are prized for their golden tone, much sought after and very valuable. That was one of the main determining factors in my decision to get a Vibro-King for my new amp. And it's a killer!
 
Re: PCB amps vs. PTP hand wired?

Ah!

Just opened my Laney today for a routine exam, repair the dead LOW INPUT jack, and installed 2 1-ohm resistors across PIN1-8 to Ground and verify bias setting.

Some PCBs amps are well-designed and got the job done. The fact is (already said) that *usually*, manufacturers using PCB's also cut down on parts cost. This is mostly why people see PCB as a bad thing.

The manufacturers using PTP/HWCB usually put in some better "critical tone components". That's why PTP/HWCB are "better sounding".

Of course, some amps do have some wimpy boards, but usually, this is the low/mid level amps.

Im still very impressed by the built quality/layout inside my Laney. I took some nice pictures again, and will post 'em soon. Stay tuned, it worth checking it.

BTW, the trick with those Laney is to plug in the LOW INPUT jack. That's their secret :)
 
Re: PCB amps vs. PTP hand wired?

ArtieToo said:
btw - did anyone else read that article from Bogner, that Stratcat linked to? Apparently, that guy didn't have great things to say about Orange Drop caps.
Click to expand...

I was wondering about that too. I always thought Orange Drops were some of the best caps available for amp purposes?

Ryan
 
Re: PCB amps vs. PTP hand wired?

Thames said:
Ah!



BTW, the trick with those Laney is to plug in the LOW INPUT jack. That's their secret :)
Click to expand...

I will 2nd that. My AOR is decent on the high gain input and phenominal in the low gain. I have to run mine wide open to get the good stuff. It will not distort w/o the master dimed.

On the PTP/PCB I have 3 PCB
72 Carlsbro TR60
96 Plexi RI ( set to mostly 68 specs)
86 Laney AOR 50.

And 5 PTP amps.

71 Traynor Bassmaster
70 or so Traynor Bassmate
65 Silvertone 1483
65 Hilgen Basso Grande
64 Gibson Mercury

They all are great 3D sounding amps, reliability has been phenominal in all of them. Original OTs, mostly original guts ( some 100 percent original and a couple with recaps) and mostly original tubes. I run them all wide open and don't feel in any way PCB is inferior tonally to my PTP amps. I dig the PTP for getting at the guts but outside of that I could care less how they are wired, I only care how they sound.
 
Re: PCB amps vs. PTP hand wired?

There are guy's that have figured out how to fix all the problems, with PCB amps, but they don't design to a price point, they design to a quality level. Take THD's for instance. Another thing is that some of the more sophisticated amps use multiple channels and stuff, would be way to big, or nearly impossible to build, if they weren't PCB. A Diezel, or a Mesa MK IV would probably not be very feasable in PTP type construction.
 
You must log in or register to reply here.

Similar threads

playas
Do Orange amps generally have a very particular voicing?
2
Replies
29
Views
2K
El Dunco
El Dunco
E
PCB evolution, you may have thought it was better by now...
2
Replies
37
Views
1K
Mincer
Mincer
contiContiCONTI
New Amp / Amp Sim Recommendations ?!
Replies
12
Views
639
donaldr
donaldr
Z
Les Pauls vs SGs... It must be summer
2 3 4
Replies
67
Views
2K
GuitarStv
GuitarStv
S
Blackouts Strat Dual-Pin Wiring
Replies
9
Views
753
jeremy
jeremy
Back
Top