Where are at,
What amp do have ?
>
I can & am an amp tech. I belive what you mean is adding a Master
Volume (gain), so that the preamp gain (existing volume control) can be
turned up higher to get a dirtier sound at a lower volume. This is a
very common mod done every day. There must be a place with room to
drill & mount the new control and that is acceptable to you.
Please give me the amp make & model. Consider that you may, or may
not, have an old amp that is valuable to others in its original state.
I am in Maine, if you'd like to send it.
Rgds,
Frank Adams