What type of UPS or power surge supressor is best for an a/v receiver and a subwoofer?”
First of all, you don’t want a UPS for an audio power amplifier. In the past, I used a small one on my VCRs so they would retain their settings if the power went out, but you would not want to have your stereo cranked on battery power alone during a blackout. There is, however, something called a line conditioner that will suit your needs. A line conditioner is not a UPS. It will not supply electric current to your devices if the power goes completely out. However, it will maintain a steady, regulated AC voltage to your electronics during brown-outs, power surges, and line spikes. This Tripp Lite model: www.amazon.com/Tripp-Lite-LC1800-Conditioner-Protection/dp/B0000514G8 is rated at 1800 watts. This should be ample for a home theater application, but you can get heavier models if needed. In addition to providing brownout and surge protection, it will provide isolat
