Mid Shift or Tone Stack Lift?

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Weathered
Posts: 67
Joined: Thu Jul 26, 2007 7:10 pm
Location: St. Paul, MN

Mid Shift or Tone Stack Lift?

Post by Weathered »

Alright, I'm starting my first scratch build design (I've built amps of varying degrees of difficulty - a couple of 18 watters, a Plexi, and a Trinity Triwatt), and I'm trying to decide what I want to do for a tone shift. I'm thinking of putting a push-pull on the mid pot, that either functions as a mid-boost or a tone-stack lift. I guess I could use suggestions on which would be smoother to implement, and could work better in the context.

So far, here are my design plans:

4xEL84, fixed bias
single channel (debating having hi/lo inputs or simply putting a switch next to the input), gain, TMB tonestack, presence (with a NFB defeat switch on the back of the amp), post-PI MV
Traditional LTP PI (not the DC biased one in a Hiwatt)
Preamp voiced somewhere between Hiwatt and Marshall (I want the punchiness of the Hiwatt tone, but with a bit more midrange grunt) with what I'd call late-70's JMP distortion level

Is there a reason that one of the two options would work better than the other? Also trying to figure out how to execute a mid-boost circuit without popping if I go that route....

Edit: I'll add that I would prefer to keep the switch on the mid pot, but would be willing to implement a separate switch if that makes wiring easier.

Thanks in advance guys - I've picked up a lot just lurking here in the past few months....
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billyz
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Re: Mid Shift or Tone Stack Lift?

Post by billyz »

Since no one else has chimed in I will. I would vote for the tone stack lift. It is pretty dramatic and gives a nice volume boost for leads. Very fat sounding. Mid shifts can be pretty subtle. Also , the tone lift is very easy to implement.
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David Root
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Re: Mid Shift or Tone Stack Lift?

Post by David Root »

Sometimes both PAB and MB together can be like Mae West said. "Too much of a good thing can be wonderful".

I would qualify that myself "it can be dirty but not muddy".

I like that in my #124.

(By mid-shift you didn't mean freqency shift did you? I interpreted it as amplitude shift).
Weathered
Posts: 67
Joined: Thu Jul 26, 2007 7:10 pm
Location: St. Paul, MN

Re: Mid Shift or Tone Stack Lift?

Post by Weathered »

Correct - I definitely had a mid boost in mind.

Definitely leaning toward a tone stack lift out of the gate, simply due to the fact that it may be a more significant effect. Sounds like it's pretty easy to build onto a push-pull pot as well.
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