Someone help 'unconfuse me' I've been seeing all of these threads from audio-buffs telling me NOT to use two sets of 8 ohm speakers (one set on the "A", the other on the "B" = A+B on at the same time), because it reduces the input impedance to 4 ohms, and will cause your receiver to overheat, and fry your power supply (???) I've seen recommendations to buy 16 ohm speakers, instead of 8 ohm ones, to off-set this--but I can't find any! Am I looking for 'hen's teeth', or do they actually exist. I'm currently running a Realistic STA-2290, 90 wpc receiver with Bose 301s series IV on "A", and a set of Kenwood LSK 500s on "B" with no apparent problems, but am I tempting fate? If it's such a 'BAD IDEA' to use "A + B" at the same time--why do receivers have settings for it? I'd expect the "A" button to pop out, (If it's buttons instead of a dial...) when the "B" button is pushed in....I find the whole concept troubling....can anyone set me straight?