Punch Replacement

My subwoofer is distorting. It is a 12" Kenwood KFC-W3012 - 4-ohm, single voice coil, 400 watt continuous RMS?

I'm powering it with an older Punch 500a2 amp. The sub is brand new. I bought it as a cheap (and temporary) replacement for another higher end sub that I think is blown. I now wonder if it is my amp. How can I find out if my amp is working properly?

The amp is probably fine. I don't think it will effectively power that sub.

Even though the amp may be rated for the power, a clean signal at that level isn't gonna happen. If you just want it to work, matching RMS power is fine. However, if you want it to sound good, The RMS rating of the amp should be at least double that of all connected subs combined.

I know, it sounds stupid, but a clean high power signal is much better for a sub than a distorted low power signal. When an amp is overloaded, the AC signal can become direct current, which will rapidly melt a voice coil even at low wattages (probably what happened to your nice sub).

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