** here's a possibility: a raven labs pmb-1.
(go to product, it's the reddish one)
i use one for mixing a piezo under the bridge of my electric bass and the regular magnetic pickup. i have a stereo jack in the bass, send a stereo cable to the pmb-1 and can mix the signals there. i also have it wired up so that a mono cable will be completely passive and bypass the piezo.
the pmb-1 is approximately 1/2 rack and runs on two 9-volt batteries. i think it's pretty hgih-quality stuff. it is an *outboard* device, so that may be a probelm for you. the upside is that you don't have to disembowel your instrument to change batteries. the other is that, if you have device failure, you can always plug in mono and finish the gig . . .
rick turner of rennaisance guitars (and all-around guitar/electronics visionary) recommended this to me and i think it has worked out quite well.
maybe this helps???
I have a stereo pickup configuration in my acoustic. A sunrise in the
soundhole and a fishman piezo under the bridge. I'm thinking about
replacing the fishman with something else. Any suggestions?
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