Ohms ?

I went to buy a replacement subwoofer for my home & most of the speakers in the home audio book are 8 ohms.My subwoofer amp is only 100 watts(peak) The blown subwoofer is 4 ohms. My Q. is If I buy a 8 ohm subwoofer will it become only a 50 watt peak? The FTC rating in the owners manual reads as such...less than 1 % THD @ 56w@ 100HZ@ 4 ohms. My 12db/Oct adjustable crossover only goes from 40HZ TO 180HZ

Basically, yes...50 watts would be what you could expect in theory. However, most amps aren't quite so perfect. It's possible your amp could deliver 55, 60, or even 70 watts into an 8 ohm load. Amps don't produce double the power into 4 ohm loads because of inefficient losses along the way (well some companies will artificially lower the 8 ohm specs to suggest they do).

You had better be using a very efficient woofer, 91 dB or more if you want to use an 8 ohm subwoofer. The higher the better. I'm guessing it will be cheaper to buy a new sub amp than find a high efficiency, 8 ohm subwoofer though.

Thanks alot! Do you do audio work for a living due to the fact that you are VERY good at helping me w/ my audio trouble.?

Nah, I've just read a some books and a bunch of internet resources to help me answer many of those same questions for my speaker building hobby...

Some things I know, some things I don't...and trust me, I'm still very much an amateur in many areas of this stuff....