Subwoofer to Amp Wattage

MacLeod

I think we're all heading to the same place but taking different roads and maybe the problem we're running into here is defining "underpowering" and "overpowering".

It takes double the amount of power to increase output by 3 db which is generally the least amount that is audible so if you take a 100 watt speaker as an example, a 90 watt amp aint underpowering nor is a 120 watt amp overpowering.

So when I say "overpowering" Im talking about using at least 200 watts on that 100 watt speaker and when I say "underpowering" Im talking about less than 50 watts.

Now, you take that 200 watt amp and although it only amounts to a measly 3 db in audible output, its DOUBLE the amount of thermal energy that the voice coil now has to dissipate. So if youre not careful with the volume control, that 200 watts will build up enough heat in the voice coil to melt it.

Now take the 50 watt amp and put it on the 100 speaker. Now 50 watts aint much and you can run out of clean power really quick. So you crank on the volume a little more to get some extra grunt and WHAMMO! Youre amp is now clipping and shooting out around 120 watts. Now 120 watts is more than our speaker is rated to handle BUT its not a whole lot more and the voice coil will have a better chance of cooling. So while you are more likely to clip the 50 watt amp, it generally will be easier on the speaker than if you were steady pumping in 200 clean watts during a spirited listening session.

This is why I generally recommend using an amp that is rated the same as the speakers. Youre not really going to get any more output from a 100 watt amp over a 75 watt amp so the chances of clipping will be the same. Also youre not going to really get any more output going with a 125 watt amp so youre not more or less likely of clipping it.

Jstas

Clipping is not that simple. There is much more to it than just a power surge.