I was looking for a thread I participated in not long ago, where someone was asking for advice about making their Stingray style bass passive. Some people were claiming that the Stingray pickup needed a preamp as it's otherwise low output. There's also the question about the preamp, and some claim you need the preamp to sound like a Stingray. I have experimented with this quite a bit years ago when I cannibalised an old OLP expanding the cavity under the pickguard and trying different picku