Detailed PRS Amp specs?

[Boogie]

Are there detailed resources for PRS amps, like schematics or just tubes used? From personal account, tube use seems to vary from amp model, widely.

Taking my personal needs as an example, the Super Dallas that I have is loaded with the following:

V1: JAN Phillips USA 12AT7
V2: Tung Sol Russian 12AX7
V3: JAN Phillips USA 12AT7
V4: Tube Amp Doctor 7025WA 12AX7

The power tubes are Winged 'C' SED EL-34s.

Is this typical? Or did the previous owner go on a preamp cocktail binge? I'm not even sure that V1 is actually V1 (listed left to right from back of amp). It would make more sense to me that V4 is actually V1 since a the TAD makes a nice primary influence and a 12AT7 as a phase inverter would be an interesting change to what I'm used to. Any documentation known? It would be nice to be more technically fluent in the amp I'm about to devote so much energy to.

 

[László]

I don't know what's in a Super Dallas that's stock, as the tubes aren't listed. But the tubes that came in my HX/DA are listed on the website:

http://www.prsguitars.com/hxda/

Mine came with JJs in the preamp section. If I had to guess, I'd say that your predecessor may have done a few preamp tube experiments.

 

[Egads]

Zombie post resurrection!

Did you ever figure out which tube is V1? The chart on the inside of my Sweet 16 PLUS is (I think) misleading. It seems to say that the 12AT7 nearest the power tubes is 1, whereas I would have assumed the 12AX7 next to the input would be V1.

As an aside, I had an odd experience with the amp. It's been occasionally (not constant, but more than once a minute) whistling and crackling. It was fairly quiet, not heard over normal playing, but rendering the amp not an option for recording. I checked and adjusted the bias, tapped the tubes, substituted each preamp tube in turn, and replaced the power tubes. It was still there.

Last night, I replaced all of the preamp tubes with like types, and...it was perfectly silent...and sounded so much better than it has (it has always sounded good, but not this good!). I ended up going back through each preamp tube, substituting the old for the new, with the other tubes still being new. I found out that the first three (starting with next to the input) each caused the issue. The fourth (V4? Phase inverter, 12AT7) was fine. I've never had three tubes start to go south at the same time.

 

[László]

I've never had three tubes start to go south at the same time.

Some tube species migrate before the winter.

 

[Egads]