Moving the volume knob

[Pbassred]

I built myself a little powered stage monitor. The Idea was that it would be fed a line level output from a mixer. It consists of :

Input jack
Preamp (opamp chip)
47k log pot
100W MoSFET power section.

The bonus with all this is that it could double as a small guitar amp. However disaster! It does the secondary task well but the line input is too hot for the preamp.

Choises -
1/ Put in a second "line" jack with a 47K in series before the preamp.
2/ Move the 47K pot to before the preamp.
3/ Put a second "hot" jack after the preamp but before the 47K pot.

Thoughts?

[GRollins]

I think you'll find that the typical arrangement is to put the volume pot before the preamp stage.

Grey

[Eva]

Obviously, low-level signals benefit from entering to the preamp unattenuated but high-level signals should be tamed.

Use a 'gain' potentiometer before the preamp and a 'volume' one before it, or add a switch to bypass the preamp, or add a 'padding' swich at the input with a resistor network designed so that signal is attenuated by 20dB (10:1) when it's activated.