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dallas
07-30-2008, 08:52 AM
Really odd question here, just go with me on this.

You have a small speaker, connected to a small amp. It's turned "on" but no sound is being played. (not that it's broke, you just aren't playing any music)

you bare a spot on the two speakers wires, touch and rub them together, will the speaker produce an audible sound?

Assume a very small amp, and very small speaker, on the order of laptop speakers. Say 10 watts.

BradJudy
07-30-2008, 08:55 AM
You may make some sound, but you'll be shorting out the amp in the process. I'm not sure how much damage this will do without much power going to the speakers, but it isn't good for the amp.

dallas
07-30-2008, 09:00 AM
You may make some sound, but you'll be shorting out the amp in the process. I'm not sure how much damage this will do without much power going to the speakers, but it isn't good for the amp.

What I'm really looking for is definitively whether this scenario can/would produce any sounds. Pops, hisses, and scratches, etc. Or would it be inaudible because the signal was already "null", or close to it?

I don't have the electronics around to sacrifice to find out... :-)

curtis
07-30-2008, 10:35 AM
I would imagine it would make some kind of sound, just not sure what.

Also, once you short the amp, the amp itself may shut down...and they you would definitely get nothing.

davef
07-30-2008, 05:01 PM
What I'm really looking for is definitively whether this scenario can/would produce any sounds. Pops, hisses, and scratches, etc. Or would it be inaudible because the signal was already "null", or close to it?

I don't have the electronics around to sacrifice to find out... :-)

There are too many variables in this scenario to give a definitive answer. It all depends on your amp or receiver.

Assuming your amp or receiver does not have short circuit protection (if the amp shuts off, there will be no output from the speakers), shorting the + / - outputs together will result in some output from the speakers. Speaker cable has resistance to it, assuming about .1 ohms for the cable and 8 ohms for the speaker, your amp will see an impedance load of a bit less than 1/10th of an ohm. The output of the speaker will be dramatically diminished (you might not hear it) but there will be voltage across the speaker -- that is, until your amp / receiver overheats and either shuts down due to thermal protections or simply breaks down...