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Trainwreck Schem ?

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11/1/1999 9:03 PM

Trainwreck Schem ?

Probably a dumb question but here goes. Looking at the Trainwreck schem on Steve A's page I have a ? on the preamp section. It looks to me like the preamp uses 3 halves of 2 or 3 12ax7's. Does it matter which halves you match up, ie.. combine the first two halves in the first preamp tube with the tone stack between the halves or what?? Or does it matter? Or should you just use 1/2 of three different tubes for some reason. I hope this question makes sense. thanks, Mark

11/1/1999 9:31 PM
BWilliamson	You can get away with only using 2 tubes for the preamp section. As I remember Speedracer saying the 3rd stage is just there for dirt. Seems to me you could really taylor the response of the amp with that tube. Maybe a nice low gain AU7, or AY7, work into a 5751 or the original AX7 for higher gain. just was the way I've been leaning lately bw

11/1/1999 9:57 PM
Mark	Would you put the tone stack between halves of the first preamp tube?

11/1/1999 10:27 PM

quote:
"Would you put the tone stack between halves of the first preamp tube?"

Yes, sorry I omitted that

bw

11/2/1999 1:56 AM
Mark	thanks!!

11/2/1999 1:13 PM

Ken would probably say...

try it both ways and see what you like better.

Ken said he doesn't mind the "Expresso" schematic being
online. He even said it was pretty darn close (BUT,
remember, since his amps are so different and tweeked,
no two amps are the same). That particular schem is
from "Orphan Annie" (again, the schem is close, but no
cigar), which won the "soundpage" shootout in Aug. 1990
in one of the guitar mags (I forget which).

He did confirm a couple values:

The .1uF going into the PI is correct; The PI
uses .1uF throughout.

The treble cap is a 500pF.

Ken said he loves and uses Kester 60/40 solder. He
said the wire plays a very important sonic role (we've
disscussed this before on AMPAGE, with wildly varing
opinions), but wouldn't disclose which wire/wires he
uses.

Mook

11/5/1999 8:08 AM
Ted Matsumura	q { Ken said he loves and uses Kester 60/40 solder. He said the wire plays a very important sonic role (we've disscussed this before on AMPAGE, with wildly varing opinions), but wouldn't disclose which wire/wires he uses. } wire in question I presume is a conductive type? Maybe metallic in the middle??

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