Originally Posted by vulturedog
This isn't bass related but it is driving me nuts so here goes! Our lead singer plays rhythm guitar. He had this bright idea about 6months ago to change his pick ups out of his LTD guitar and put EMG active pick ups In. Well ever since he has this gawd awful feed back if he turns towards his amp or turns a particular volume knob. he did take it back a couple times to have it fixed but they keep saying nothing is wrong! Our last show his amp blew up right at the end of our 4th song ( it's a brand new amp)so we continued with lead guitar and me ( to my delight anyways) my question is if an active pair of pick ups are wired wrong could it actually blow up an amp? I don't think pick ups powered by 9volt could cause such damage but could it? Just wondering!
It depends on what you mean by "blow up" I presume you really mean his amp quit. Normally the 9 volts can't ruin an amp even burnout the front end preamp which is made to take that much overload.
It is feedback that "blows up" an amp. It drives the amp to max clipping power which can take out speakers and output stages. The fact of cranking volume or turning toward amp causing feedback is a hint. Normally guitars with magnetic pickups (active or passive) do not produce feedback except under extreme circumstances (Henrix clone players with guitar right in front of speakers but that is more a lead thing). Exceptions to this are if guitar is hollow body or if pickups are microphonic. If the guitar is hollow body then too bad, keep the damn volume down!
But if the pickups are microphonic they will pick up sounds even if there
are no strings on the guitar (that is the test!) If you tap on them with something non-metallic and they make noise with no strings on the guitar then there is a problem. It can be all sorts of things. improperly potted pickups, mounting springs and hardware, or just bad pickups.
The final thing is that if active pickups have built-in EQ which boosts certain frequencies to give them a certain tone, the pickups will have a much greater tendency to feed back than if the response was "flat". Also a different tone may have him playing with higher gain than before which brings him closer to feedback.
And once you start having fedback, unless the amp has built-in feedback protection limiting, it can overload it and/or the speakers and say good bye.
But no, I don't think that "wrong wiring" is a cause of this.