Wiring In PRS Amp Lines

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Too Many Notes
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The PRS single-channel amps, like the HXDA, DG30, and a few others that aren't around any more are true hand-wired amps; that is, the circuit boards are populated by hand, with through-hole wires, eyelets hand-tapped, and no tracers on the circuit boards, etc. Also all tubes are chassis-mounted.

This is confirmed in this PRS video with the 25th Anniversary model (from which several PRS single-channel amps are derived); of course, it also makes the amps a bit more expensive (and totally worth it IMHO due to the sound):


It seems that other amps, like the Tuxedo series, were hybrid circuit boards, with some hand-wired parts, but with traces on the circuit board and some tubes mounted on the circuit boards.

I'm just curious as to the Custom 50 amps; are they more or less hybrid designs like the Tuxedo series, or are they true hand-wired amps like the HXDA and the other single-channel models?

Anyone know?
 
Cool -- I think I met Jeff when I picked up my cabs from them several months ago. Will have to watch these videos. My MDT is definitely hand-wired.
 
Yes, the MDT, Dallas, Super-Dallas, Original Sewell, 25th Anniversary, Paul's, Recording, HXDA, Blistertone, DGs -- basically all the single-channel models -- are hand-wired.

I'm curious about the Custom 50 - the thing sounds great. I know it doesn't make very much difference to the tone whether it's circuit board or HW, but curiosity impels me to find out.
 
Pretty sure the Archon has some tracers in the board, techinically making it PCB(though doesn't appear to be a lot). Probably considered a hybrid with all the flying leads all over? There's a lot of handwiring there as well. Not sure sure on the Custom 50.
 
Forgive the sloppy photo, but here's a gut shot of the Custom 50. To my surprise, there appears to be very few PCB leads on the boards. I assumed there would be a fair amount of PCB, although the majority being hand wiring, but to my untrained eyes it is almost all turret board hand wiring. Exception being the footswitch leads (coming in from the lower left on this shot), which don't affect the tone at all.

27628057674_085fcbb088_z.jpg


Compared to the PCB fiasco in my SE30, this actually looks pretty simple!
 
Forgive the sloppy photo, but here's a gut shot of the Custom 50. To my surprise, there appears to be very few PCB leads on the boards. I assumed there would be a fair amount of PCB, although the majority being hand wiring, but to my untrained eyes it is almost all turret board hand wiring. Exception being the footswitch leads (coming in from the lower left on this shot), which don't affect the tone at all.

27628057674_085fcbb088_z.jpg


Compared to the PCB fiasco in my SE30, this actually looks pretty simple!

Thanks so much! Yes, clearly a hybrid, but a lot of hand work as well. It's very interesting how PRS makes things work so nicely. I really love the Custom 50 sounds.

Much appreciated!
 
Forgive the sloppy photo, but here's a gut shot of the Custom 50. To my surprise, there appears to be very few PCB leads on the boards. I assumed there would be a fair amount of PCB, although the majority being hand wiring, but to my untrained eyes it is almost all turret board hand wiring. Exception being the footswitch leads (coming in from the lower left on this shot), which don't affect the tone at all.

27628057674_085fcbb088_z.jpg


Compared to the PCB fiasco in my SE30, this actually looks pretty simple!
Wow, that's a LOT more complex than, say, a HXDA/25th. Thanks for posting :)
 
I think PRS's approach is interesting. The components are actually all mounted on PCB with the exception of the components soldered directly onto the sockets. You can't see them, but the traces on the underside of the board connect the top mounted components according to whatever the schematic is.

Em7 once said that somebody at PRS told him that the philosophy was to improve on the ease of maintenance associated with turret board construction which typically involves individual wires soldered between turrets on the underside of the board to make the necessary component connections. If you need to swap out a component on the top side, wires attached to the turret underneath often come undone when you de-solder the component (if you're ham handed with the iron anyway...) Sounds like a good philosophy to me. The wires associated with switches and front panel controls and whatnot always have seemed a bit haphazard in terms of routing and organization to me, but that's just a cosmetic thing.

I'm not one that believes that there is a tonal difference between "hand wired" in whatever flavor and PCB amps, in whatever flavor. It's sure easier to maintain or mod with the type of construction that PRS uses.
 
I think PRS's approach is interesting. The components are actually all mounted on PCB with the exception of the components soldered directly onto the sockets. You can't see them, but the traces on the underside of the board connect the top mounted components according to whatever the schematic is.

Em7 once said that somebody at PRS told him that the philosophy was to improve on the ease of maintenance associated with turret board construction which typically involves individual wires soldered between turrets on the underside of the board to make the necessary component connections. If you need to swap out a component on the top side, wires attached to the turret underneath often come undone when you de-solder the component (if you're ham handed with the iron anyway...) Sounds like a good philosophy to me. The wires associated with switches and front panel controls and whatnot always have seemed a bit haphazard in terms of routing and organization to me, but that's just a cosmetic thing.

I'm not one that believes that there is a tonal difference between "hand wired" in whatever flavor and PCB amps, in whatever flavor. It's sure easier to maintain or mod with the type of construction that PRS uses.

Ah, that makes sense. Taking my chassis out was as far as I dare to go, so I'll just take your word for it! I did hear once, that mainly what PRS used/uses PCB leads for were connections to ground that would affect tone less... not sure if that was true in theory or in practice either. But I heard it on the interweb, so it's now undeniable fact.

Oh yeah I get, plus loop, boost and reverb yeah?

At the risk of dicussing RRP, the HXDA is a more expensive amp, even though it is a lot less complex. I'm assuming conponents (e.g. Sozo caps, Cinemag vs Heyboer?), labour and R&D have a lot to do with that?

I'm sure you're right, the 2 Channel "C" amp was higher in price than the comparable H, which I believe was in large part due to the Cinemag, and I wouldn't be surprised if the other components on the HXDA are more expensive as well. IIRC, the the old plexi transformers were quite challenging for PRS to recreate because they were so rudimentary and inefficient - basically, it's difficult and expensive to make something to such "undesirable" specs by today's standards, because technology and manufacturing have evolved specifically to avoid that kind of performance. Of course, that statement is true of tube amps in many ways.
 
I think PRS's approach is interesting. The components are actually all mounted on PCB with the exception of the components soldered directly onto the sockets. You can't see them, but the traces on the underside of the board connect the top mounted components according to whatever the schematic is.

Aristotle, that's incorrect as to the CAD single channel amps as of when I last checked.

If you watch the video I posted (from 2010) starting about 40 seconds in, right around the 45 second mark he pulls out a board and says, "It is all hand-wired, hand built. There are no traces on the circuit board."

That, and other sources "in the know" have told me that there are no traces on the underside of the boards on those amps.

They are completely hand-wired, at least as of 2014 when I got my DG30 and as of last year when I got my HXDA that was built in late 2014.

So I figure you're talking about the other amps, or have you got some specific (perhaps more recent?) info I don't have? I can always double-check with Doug at PRS if there's a question at all.

Experience with lots of amps over the years has taught me that hand-wired and PCB amps do sound a little different. Not necessarily better, just different. It's very hard for me to put into words what I hear from hand-wired amps, but I do hear a difference. The problem, of course, is that I haven't had hand-wired and PCB versions of identical amps.

So I'm talking in very general terms, and that's always dangerous due to small sample size. Nonetheless, I am willing to go out on a limb and say I think there's something to it.

Oh yeah I get, plus loop, boost and reverb yeah?

At the risk of dicussing RRP, the HXDA is a more expensive amp, even though it is a lot less complex. I'm assuming conponents (e.g. Sozo caps, Cinemag vs Heyboer?), labour and R&D have a lot to do with that?

Hand wiring takes longer. The 'glass boards the parts are on are thicker (this confirmed by Doug Sewell). The eyelets for the wiring are punched and installed by hand. The preamp tubes as well as the power tubes are chassis-mounted. Many of the components are more expensive, Etc., etc. It's just a more time-consuming thing to build.

The head boxes are a little nicer, with the inset for the handle and the added panel for the controls that's attached to the chassis in an unusual way.
 
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Haven't pulled my dg30 apart but my HX/DA and MDT have this construction, and they are CAD. The explaination was from Em7 who talked to Doug Sewell. Personally, I think it's the best of all worlds.

I think what the guy in the video meant is that they are discrete components hand soldered to posts. Still qualifies as hand built to me.

Em7 even found out the thickness of the clad and traces when he spoke with Doug.
 
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Haven't pulled my dg30 apart but my HX/DA and MDT have this construction, and they are CAD. The explaination was from Em7 who talked to Doug Sewell.

I think Em7 had a 2 Channel H, and was referring to that. If not, I think he's in error, but I'm only too happy to eat my words if I'm wrong!

Simple solution: I will check. I'm pretty sure it's hand-wired in the traditional sense. I've sent off an email to the amp guys to find out. I'll post the info in whatever reply I get.
 
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EDIT: This has some errors, because I misinterpreted the video a little. However, I'm leaving this post as-is, because it was replied to by members in the thread.

I heard back from Doug Sewell; he sent me a link to this particular 2010 video that explains and shows the differences in PRS' three different processes used for Maryland amps. He describes these three different lines and how they are wired at about 4:30 in the video.

Confusion might arise from the fact that a great deal of hand wiring takes place in each process, and in fact, Doug refers to both the first and second level amps as "hand wired." The components aren't wave-soldered onto the board, as they are with some mass produced amps. But the top line of PRS amps are in fact truly traditional, hand wired amps.

First level: totally hand wired with no circuit board tracers at all. From what I can see, these are the CAD amps, and the examples shown are the 25th Anniversary and Dallas amps. In the video Doug shows both sides of these boards at around 4:30 in, and the absence of tracers on the board is quite obvious.

Second level: hand wired with tracers on one side of the board. While he refers to these as hand wired, he also says they aren't 100% hand wired. They have slightly thinner boards, but very thick tracers. I believe that these are the H and C lineage amps, such as the Custom 50. I don't know about the Archon. The video isn't specific on this.These are the amps that I'm going to guess Em7 was referring to when he talked with Aristotle.

Third level: tracers on both sides of the board, thinner board than second level. These are specifically referred to as the Black and White amps. I'm not sure which current amps are made this way currently, if any.

More details from the video:

The first level I mentioned are the "totally" hand wired amps, like the 25th Anniversary, Dallas, etc., that he shows in the video. In addition to being "totally" hand wired amps (he shows the Dallas and the 25th Anni that is the basis for the HXDA, for example) - one can see that these have no traces, and have 1/8 inch thick eyelet boards and are 100% hand-wired with no board mounted tubes.

The second level he refers to as "hand wired amps" that have some circuits with very thick tracers on one side only; these are the amps with the lineage of the "H" and the "C". In the video these are shown at around 4:50 in. I couldn't tell from the boards shown how the preamp tubes are mounted.

The third level are then described as the boards used for the "black and white" amps, that have more printed circuits that are double-sided. The preamp tube socket mount areas are clearly on the board. This is shown in the video at around 5:24 in.

Clearly, amps like the 25th Anniversary, Dallas (and I believe this applies to the other CAD amps like the HXDA and DG30 but I didn't ask for a model-by-model breakdown), have no circuit board traces.


Now, if you add in the video I first posted where the amps' assembler also says there are no circuit board traces on the top line amps, I think it's pretty clear that there are no traces on the top line amps.
 
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