A Chambered Body Feedback Question

[Mitch]

Hi everyone

I am in the planning stages of a new 4-string bass build. I have based the design on a Fender Jazz Bass with a 1/4" to 1/2" thick, flat top (possibly western red cedar) and a hardwood back. Anyway, I want to heavily chamber the body to gain the warmer, more resonant tone of a hollow body but I am worried this may cause feedback issues. For this reason, I think it may be a good idea to incorporate a centre block, and this is my quandary, I'm not sure if I need to have a full-length centre block, a block only under the pickups or a block only under the bridge. I'm aware that there are various different causes of feedback (sympathetic resonance of the strings, microphonic pickups etc.) but I don't know which type is most likely to cause problems. Or will the top be thick enough to fully chamber and have no feedback issues? Would a full centre block still allow me the tone I am looking for?

Thanks

Mitch

[jeremyp]

I recently build a pine back 1/4oak top 4003 styled bass, with nothing more than minimal center block and a 1/2 ledge around the edge of the body I've only had problems with microphonics and not so much actual feedback (i might not play loud enough haha). as for what you should do, what kind of pickups are you using and what kind of bridge? you'll need a way to mount these things.

[Mitch]

I recently build a pine back 1/4oak top 4003 styled bass, with nothing more than minimal center block and a 1/2 ledge around the edge of the body I've only had problems with microphonics and not so much actual feedback (i might not play loud enough haha). as for what you should do, what kind of pickups are you using and what kind of bridge? you'll need a way to mount these things.

It's basically a Jazz Bass setup. It will have 2 single-coil pickups, though I haven't chosen any particular model yet. The bridge will be just a standard hardtail. Since the top will be quite thin, I will glue a block under the bridge (not touching the back of the cavity) or leave a block of back wood under the bridge. I can't say I have ever had problems with a bass guitar feeding back before but then again, I have only ever played solid bodys.