Neutron Mutron Volume Pot mod help??

[Soulchief]

Hi all, I have a few Neutron questions regarding 'adding a Volume Pot' and 'Output Impedance':

1--Trying to add an 'Output Volume Pot' to a Neutron (Mutron) build, would anyone have a recommendation as to what value/taper pot to use?

2--Also, does the last resistor (R21) determine the 'Output Impedance'?

3--Adding it to the very end of the effect signal path right before the switch, would I still leave in the last Resistor R21 or does the Pot replace that?

4--If leaving R21, should it be changed to a lower value (see other values below)?


Here is some info I have found on the predecessors:
     Mutron: Output Impedance = 600 Ohms / R21 = 560 Ohms
     QTron: Output Impedance = 250 Ohms / R21 = 150 Ohms
     TruTron: Output Impedance = 150 Ohms
     MicroTron: Output Impedance = ?, but does has a 250K Volume Pot

Schematics:
http://www.generalguitargadgets.com/pdf/ggg_neutron_sc.pdf
http://www.geofex.com/PCB_layouts/Layouts/neutronpub.pdf






If anybody has any insight or ideas to help me out I would be extremely grateful

Thanks

[thermionix]

That schematic is a missing most values.  Did you build it with regular true bypass?  A volume pot could also serve as a pulldown at the end.  Personally, I would try A100K and see how that worked out.  I have no clue how to calculate what it should be.

[Soulchief]

 I just added the GGG schematic with the values if that will help any further..

[idy]

Mad Bean's "Naughty Fish" uses a 100kb after the 580ohm resistor. I have built a handful of these and it works fine.

[Soulchief]

Thanks! I forgot about the 'Mad Bean Naughty Fish'..

Come to think of it I've never been able to find a schematic for that to compare so it slipped my mind.
Does anyone have the 'Naughty Fish' schematic available?

If anyone else has any insight, thoughts, or ideas a 'volume pot'.. I'm eager to listen.

[idy]

You get the schematic at the MadBean website.

[Soulchief]

Thanks I just found the MB Naughty Fish schematic!

Currently I have these schematics: RG Neutron, GGG, Orig Mutron, Modded Mutron, Orig Qtron, Naughty Fish.
They are all great for comparisons..

I'm building a Boost in front of the Mutron Circuit and will definitely be needing a Level/Volume/Output Pot..


Anyone else have any thoughts on adding 'Mutron' Volume Pots?