Quayhog
Well-known member
I dislike the sound of the usual acoustic guitar amps with piezo pickups. I'm modding a Grommes S-60 for use with piezo equipped acoustic instruments.
One channel for a string bass and another for fiddle and mandolin.
This amp sounds spectacular with my electric bass. There are two other channels awaiting their voicing for specific instruments. The piezo pickups have a one Meg output impedance. Just changing the grid load to a very large resistor makes them sound just OK. Certainly better than solid state acoustic amps. I've tried the usual 1 meg and various larger ones randomly taken from my parts bins.
Any suggestions for circuit changes are welcome.
Thank you.
Jonathan Horne
One channel for a string bass and another for fiddle and mandolin.
This amp sounds spectacular with my electric bass. There are two other channels awaiting their voicing for specific instruments. The piezo pickups have a one Meg output impedance. Just changing the grid load to a very large resistor makes them sound just OK. Certainly better than solid state acoustic amps. I've tried the usual 1 meg and various larger ones randomly taken from my parts bins.
Any suggestions for circuit changes are welcome.
Thank you.
Jonathan Horne
