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lbridges · 05-16-2008, 10:21 PM

Quote: Originally Posted by rijndael

1) If i am wrong and resistance itself does not hurt the speaker...please let me know...cause that was one thing i thought hurt speakers...
2) since the current flowing from the amplifier stays the same (100W is 100W)...doesnt he end up with 100W at 4ohm by doubling the length of wire but with less stress on the amp itself creating less heat and thus longer life of the amp?

1) Resistance doesn't hurt the speaker. What hurts speakers is overdriving the amplifier. When overdriven an amplifier begins to turn a musical sine wave into a square wave. This causes overheating as well as putting out a lot of power at frequencies not intended (a pure square wave would have an infinite frequency spectrum and a 100% duty cycle on the speaker - it could never cool down).

2) Assume a speaker with 2-Ohms Resistance. The wire leading to it will likely have less than 0.1-Ohm Resistance, resulting in the amp 'seeing' 2.1-Ohms. Doubling the length of the wire then results in the amp seeing 2.2-Ohms (the speaker didn't change). A potentially nasty side effect would probably be induced by too much wire - coiling a wire would cause unwanted inductance - resulting in a low-pass filter effect.

05-16-2008, 10:21 PM	#23
lbridges Variable Bitrate Join Date: Jan 2007 Location: East Central FLA Posts: 238	Quote: Originally Posted by rijndael 1) If i am wrong and resistance itself does not hurt the speaker...please let me know...cause that was one thing i thought hurt speakers... 2) since the current flowing from the amplifier stays the same (100W is 100W)...doesnt he end up with 100W at 4ohm by doubling the length of wire but with less stress on the amp itself creating less heat and thus longer life of the amp? 1) Resistance doesn't hurt the speaker. What hurts speakers is overdriving the amplifier. When overdriven an amplifier begins to turn a musical sine wave into a square wave. This causes overheating as well as putting out a lot of power at frequencies not intended (a pure square wave would have an infinite frequency spectrum and a 100% duty cycle on the speaker - it could never cool down). 2) Assume a speaker with 2-Ohms Resistance. The wire leading to it will likely have less than 0.1-Ohm Resistance, resulting in the amp 'seeing' 2.1-Ohms. Doubling the length of the wire then results in the amp seeing 2.2-Ohms (the speaker didn't change). A potentially nasty side effect would probably be induced by too much wire - coiling a wire would cause unwanted inductance - resulting in a low-pass filter effect.