speaker choice to keep amp cool


2015-09-10 9:28 pm
Hi. I have a 4 channel amp driving 4 6X9 speakers in my car. The amp is rated for both 2 or 4 ohms. I'm going to buy new speakers and trying to decide the best speakers to get in order to keep my amp cool (I've had overheating issues when it gets hot out) - assume it is exactly the same speaker in either 2 or 4 ohm options.

If I go w/ 2 ohm speakers, I understand that it makes the amp work harder, and can cause it to heat up more than if I use 4 ohm speakers...

However, if I use 4 ohm speakers, then the power supplied to the speakers is reduced (85W at 4 ohm vs. 120 W at 2 ohm). If I use 4 ohm speakers, I'm assuming I may have to adjust the gain higher on the amp to get the same relative volume as if I was using 2 ohm speakers, so will that cause the amp to work just as hard (and get just as hot) as if I used 2 ohm speakers and had the gain adjusted lower?

All else being equal, you probably won't hear a significant difference between 2 and 4 ohm speakers. If you were considering eight 4 ohm speakers instead of four 4 ohm speakers, then that would be an audible difference.

If heating is a problem, you could use a fan to help keep the amp cool. Force the air from the end. This will not only cool the heatsink but will force air through any vents on the end of the amp (if it has end vents).