Making a very simple volume control

[Wormwoodprophecy]

I have a lee Jackson gp1000 guitar Pre amp that I've modified a bit (cathode resistor and bypass cap) that goes into a digitech gsp1101. Where does this all come into play, well the lee Jacksons output is SOO hot it overloads the Gsp. I can have the volume less then 1 and it becomes managable but the sweet spot is so small.

If I just took a 50k pot, would this reduce volume without changing much tone? I don't mind a loss of some highs but I'm not looking for an expensive or complicated solution.

A better solution would be to mod the Pre amp so it's output is more ideal but with a tour 3 days away... Well you get the point.

[Mooly]

The answer depends on the output impedance/drive ability of the preamp and the input impedance of the GSP1101

Not familiar with either product but when you mention valves we are usually talking "poor" (compared to solid state) drive ability. If the preamp can drive 50K then there's no problem and 50K is low enough that it shouldn't alter the "tone" as you put it. The pot forms a low pass filter in combination with the input capacitance of the GSP1101.

So you have two compromises... lower value resistance is "better" for an attenuator if the preamp can drive it, higher resistance is better if it can't but the tradeoff could be a low of HF if the input capacitance (the capacitance seen by the pot wiper) is high. Ther valve stages will be AC coupled so again there is a filter action. This time high pass. So lower value pot could decrease bass output depending on value of coupling caps.

Also if you use a pot then I would then measure the resistance values when it's set OK and make a fixed attenuator.