I have an old stereo amp that I am using for my TV sound system. I have my "A" channel into a set of Polk M20's. I also have my "B" channel into a set of passive subs. It sounds good, but I want to add a third set of speaks. Since I do not want to drop below 8 ohms, I have an issue. I have added the third set of speaks in series with the subs, and it is weak as hell being 16 ohms. Is it possible to hook two speakers up in series/parallel? If I run the + out of the amp into the + on the speaker, the - out of the speaker into the + of the sub, and the - out of the sub into the amp, I get series. Can I keep that, but run two more wires from speaker + and -, into the + and - of the sub? Will that blow the amp to pieces, or will it result in an 8 ohm resistance? Please help.