larger MID Pot, which pot

[GeekG]

Hey dear amp freaks,

I own a plexi clone and want to try a
250 k midpot instead of the 25k.

Can i use a laying around guitar (volume) pot?

I want to try if i can go from slightly scoop to 'normal 25k dimed' to boosted... wirh this pot.

I read it works on fender amps not marshall but it should work too, aint it?
Idea is to get more of a tweed sound if wanted (my amp has no negative feedback also)

Will the guitar pot be ok or do i need a special pot..
Log, linear, or audio?

Thanks alot... if you can point me to some topic that handles what i want, Thats fine too.

[Carbia]

250k is too much.

Anyway, you can try with a 250k one, and try with resistors in parallel to lower the value.

[Roe]

try 50k

[GeekG]

Thanks for suggestions guys!

1)so if i take a 50k pot.. or 100k
Which..
Linear. Audio or log?

2) so i can also try 250 k guitar pot. And when i want to lower the resistance i should put 2 of the same rs between the outside and the middle lug?

Or just between one side and middle?

Lets say i want 100k from 250k..
250 i thought would fit because there exists a 'raw' control in some amps that is basically a 250 mid pot.. i read about it.. i dont have to turn it up all the way..

The idea is a sweep from stock to midboost to almost completely bypassing tonestack..

Cheers

[GeekG]

Just had another idea.

50k pot

And then a switchable large resistor to ground for almost completely bypassing the stack..

Do i can dial in some tones at the pot.. and then soloboost per footswitch..

The switch is already there.. 1m resistor.
Think this will be best solution..

Right? Because i crank the mid knob anway right now..

So i just have to ger the right kind of pot.. not sizewise but type wise... log. Audio . Or linear..

Thanks for suggestions

[darkbluemurder]

My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable. A 250k log pot would give you similar results but is more difficult to control IMHO.

Cheers Stephan

[Roe]

anything from ca 27k to 36k is historically correct. most newer 50k pots read ca 45k

[GeekG]

My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable.

Cheers Stephan

Thanks Stephan, i used the trick you suggedted in some other thread about a small to medium sized cap across the midpot to only boost mids and not so much highs.. worked like a charm on my 25k pot..

Would you advise to keeping it for the larger pot as well, or should i remove it or adjust the cap value? Of course i could test it but i'd live to hear your humble opinion.

Cheers Georg

[darkbluemurder]

My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable.

Cheers Stephan

Thanks Stephan, i used the trick you suggedted in some other thread about a small to medium sized cap across the midpot to only boost mids and not so much highs.. worked like a charm on my 25k pot..

Would you advise to keeping it for the larger pot as well, or should i remove it or adjust the cap value? Of course i could test it but i'd live to hear your humble opinion.

Cheers Georg

To get the same sonic effect I would adjust the cap value to 1/4 th of the value used for the 25k pot.

Cheers Stephan