jshep205gti 3 Posted March 28, 2007 Hello.... I know I'm right but I don't know why... Basically my mate has a 2 channel amp and thinks it is a good idea to run 2 speakers fom each channel. As in just jam 2 +ve and 2 -ve cables into the ports. I've told him it is a rubbish idea, but I can't exlpain why. I think it is because of the fact that the amp is working too hard. Just had a thought though.... the power of the speakers must matter too?? Is this something to do with Ohms?!?! There must be a quality website out there that tells all about ICE?!?!? Thanks for all input. Shep Share this post Link to post Share on other sites
benlilly 0 Posted March 28, 2007 Hello.... I know I'm right but I don't know why... Basically my mate has a 2 channel amp and thinks it is a good idea to run 2 speakers fom each channel. As in just jam 2 +ve and 2 -ve cables into the ports. I've told him it is a rubbish idea, but I can't exlpain why. I think it is because of the fact that the amp is working too hard. Just had a thought though.... the power of the speakers must matter too?? Is this something to do with Ohms?!?! There must be a quality website out there that tells all about ICE?!?!? Thanks for all input. Shep Hi Shep, This is very likely a bad idea unless the speakers are 8ohm units or higher. When you connect the speakers as described, you are wiring in 2 units in parallel, this halfs the impedance seen by the amp and doubles the current drawn. This in turn will increase the ammount of distortion the amp will produce and also the heat. If the impedance gets really low, you could blow it. Check the impedance of the drivers and also the recommended amp load. The formula for calculating the impedance for parallel resistances is 1/Rtotal=1/R1+1/R2+1/R3......+1/Rn If you work this through you'll find that if you wire 2 equal drivers in parallel you will half the impedance, 3 in parallel the result will be a third and so on. Share this post Link to post Share on other sites
veloce200 3 Posted March 28, 2007 It is indeed all about ohms. find out what the amp can drive comfortably eg 4ohms. then check the speakers - eg 2 x 8ohm speaker in parallel and the amp will "see" 4 ohms. Some car stereo amps will go as low as 1 ohm. However plug a 4 ohm speaker in an amp that will drive 8 ohms min for example and it could burn out or if it has one an internal fuse will blow. The lower the ohm the harder the amp works but also the greater the soundlevel. So to sum up good idea if they are compatible. You can wire in series as well but this is more for distribution of more speakers or matching uncompliant equipment - eg car stereo speakers to old hi-fi amplifiers. Share this post Link to post Share on other sites
Paintguy 0 Posted March 28, 2007 I agree with all the above, it depends on the amp and speakers really. If we make the assumption that they are 4 Ohm speakers (they invariably are) then as long as his amp is stable to 2 Ohms, he won't really have a problem. The amps power supply will draw slightly more current, it'll produce more heat, and the THD ('distortion') will almost certainly be higher, but there's nothing significant to worry about. As a rule of thumb, if his amp can be bridged into one channel (to run a sub for example) then it's stable to at least 2 Ohms. Share this post Link to post Share on other sites
