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Hoffman Amps Forum image Author Topic: add mid pot to tonestack  (Read 3310 times)

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Offline joesatch

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add mid pot to tonestack
« on: October 03, 2025, 10:13:40 am »
i think this is a bassman tonestack. unsure. where would i add a mid pot to it?

Offline shooter

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Re: add mid pot to tonestack
« Reply #1 on: October 03, 2025, 10:40:29 am »
personally I'd add it to the guitar and leave that TS alone.  2nd option is to use the Treble/Bass pots to "bring out mids" by attenuating the highs n lows
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Offline joesatch

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Re: add mid pot to tonestack
« Reply #2 on: October 03, 2025, 11:25:47 am »
personally I'd add it to the guitar and leave that TS alone.  2nd option is to use the Treble/Bass pots to "bring out mids" by attenuating the highs n lows

i think i'll scrap this TS and just run a normal cathode driven TMB tonestack. All kinds of voltage dividers and weird things going on with this

Offline shooter

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Re: add mid pot to tonestack
« Reply #3 on: October 03, 2025, 12:36:59 pm »
 :laugh:


now ask guitarists if that makes any difference when they play. sometime what makes sense electronically make NO sense to musicians.
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Offline astronomicum

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Re: add mid pot to tonestack
« Reply #4 on: October 03, 2025, 01:15:16 pm »

i think i'll scrap this TS and just run a normal cathode driven TMB tonestack. All kinds of voltage dividers and weird things going on with this

Would’nt it be a good idea to understand how this tone stack is affecting the gain profile before replacing it with something else?

Offline tubeswell

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Re: add mid pot to tonestack
« Reply #5 on: October 03, 2025, 03:48:11 pm »

i think i'll scrap this TS and just run a normal cathode driven TMB tonestack. All kinds of voltage dividers and weird things going on with this

Would’nt it be a good idea to understand how this tone stack is affecting the gain profile before replacing it with something else?


I’m not 100% certain that joesatch’s  tone-stack is in an amp he has built at this stage - I’m 95% confident this is an idea he is batting with.
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Offline tubeswell

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Re: add mid pot to tonestack
« Reply #6 on: October 03, 2025, 10:36:01 pm »
Hey Joe - this is where you might be goin', or not. I redrew that tone stack a couple of different ways to help you see where to look for a 'mid pot' position.

I vote for swapping out the 220k resistor in red ('R 13') with a 250k pot wired as a variable resistor. It's more of a 'slope' control idea but it might have the funky effect you're looking for
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

Offline tubeswell

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Re: add mid pot to tonestack
« Reply #7 on: October 04, 2025, 12:51:40 am »
Or this
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

Offline jjasilli

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Re: add mid pot to tonestack
« Reply #8 on: October 04, 2025, 07:32:03 pm »
I agree that the tone circuit looks like that of a Bassman 5e6. This is not a tonestack.  It's a treble bleed circuit plus a bass bleed circuit, which are interactive.


There is no filtering for a mid control.  The 5e6 is reputed to have great mids.  Do you want more mids, or less???


Theoretically, you get more mids by decreasing treble & bass; then turn up the volume to make up for signal loss.  Reverse this for less mids.


For more info google Bassman 5e6 mid control.

Offline Willabe

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Re: add mid pot to tonestack
« Reply #9 on: October 04, 2025, 08:21:43 pm »
That's the Bassman Rory Gallagher used, a 5E6. With a Range Master treble boost in front. 

Irish Tour live album rig/sound.

 


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