Hi, I have a Yamaha bass with a Mike Pope Flexcore 2.2 stk preamp. Wonderful preamp and I’m very happy with it except for one problem. It has a bass/treble stacked board and a low-mid/high mid stacked board. In active mode the B/T board is dead quiet, whether cut or boosted. The low mid/hi mid board is dead quiet when everything is cut, there is a moderately loud hiss at the detente position, and a VERY loud hiss/white noise when fully boosted. The only way I can play the bass in active mode without driving myself crazy is to fully cut the low and high mids, and that of course takes away the whole point of using the preamp. I know Mike will be able to troubleshoot this but I wanted to tap the collective wisdom of the TB community first. Any ideas? Thanks in advance. P.S. Everything—control and pickup cavities, bridge—is fully shielded and grounded.
I checked the main gain trim pot and found it turned all the way up. Turned it down and that helped significantly. I still need to adjust the center frequencies for the low and hi mids, but I’m waiting on some jumper shunts from Mike Pope to do that.
