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Marshall Mods / Trace Allen / etc

9/26/1999 12:44 PM
SpeedRacer	Marshall Mods / Trace Allen / etc Hey all.. hooked up with Trace after the AES show yesterday and we hung out at casa speed for some 100W JMP amping.. Couple interesting things: 1 - the amp we worked on is an ex-Brian Adams 100W head that had been Butchered, and Trace had put it right. This thing was set up for 6550's and sounded GREAT. A real surprise to me actually. It was using NOS GE's and sounded every bit a Marshall. Blew me clean away. We were going to convert it over to EL34's but canned the conversion because it sounded so good. Really! 2 - using my handy (and dandy) CD cap dub box, we did a little testing. A few weeks back TA got some head scratchin' responses to one of his mods, (to be honest I had to wonder about it as well!) where he put a 330pF cap in \|\| with the PI input cap. Well, I'm here to tell you to toss the calculators down the garbage chute.. it does actualy do something! Weird science.. With the cap in parallel the highs smoothed out and there was a "fatter" midrange. Less detail, but more "beef" to the tone. Good for soloing for sure. Brought out the "Billy Gibbons" kinda vibe. Why it works, who knows. Comb filtering from phase/freq differences between the two caps?(WAG) All I can say is try it (put it on a switch and go back a forth a few times and you'll hear it. For real.) One more reason to "tweak with your ears"..

9/26/1999 12:44 PM

SpeedRacer

Marshall Mods / Trace Allen / etc

Hey all.. hooked up with Trace after the AES show yesterday and we hung out at casa speed for some 100W JMP amping.. Couple interesting things:
1 - the amp we worked on is an ex-Brian Adams 100W head that had been **Butchered**, and Trace had put it right. This thing was set up for 6550's and sounded GREAT. A real surprise to me actually. It was using NOS GE's and sounded every bit a Marshall. Blew me clean away. We were going to convert it over to EL34's but canned the conversion because it sounded so good. Really!

2 - using my handy (and dandy) CD cap dub box, we did a little testing. A few weeks back TA got some head scratchin' responses to one of his mods, (to be honest I had to wonder about it as well!) where he put a 330pF cap in || with the PI input cap. Well, I'm here to tell you to toss the calculators down the garbage chute.. it does actualy do something! Weird science.. With the cap in parallel the highs smoothed out and there was a "fatter" midrange. Less detail, but more "beef" to the tone. Good for soloing for sure. Brought out the "Billy Gibbons" kinda vibe. Why it works, who knows. Comb filtering from phase/freq differences between the two caps?(WAG) All I can say is try it (put it on a switch and go back a forth a few times and you'll hear it. For real.) One more reason to "tweak with your ears"..

Replies:

Fj which # pin on which tube socket do... -- 9/26/1999 3:12 PM
BWilliamson I have this mentioned to me in kind... -- 9/26/1999 11:04 PM
Trace q{Hey all.. hooked up with Trace af... -- 9/27/1999 1:51 AM
Eth "All capacitors become inductive as... -- 9/28/1999 4:30 PM
John S. Re: Trace Allen's mods and the "Meat Switch" -- 9/28/1999 8:45 PM
Mark Abbott Re: Marshall Mods / Trace Allen / etc -- 10/9/1999 12:45 AM