After reading Alan's post, we should go back to the drawing board.
I used the configuration that I suggested successfully when I was a teen with my Kenwood stereo amp and cheap, Realistic speakers. It was, I thought, a good way to get the centre image that my left and right speakers couldn't muster. Maybe I was just lucky but it appeared to work.
So I just tried this on my wife's Sony book-shelf system. I used my old no-name brand center channel speaker. I cranked the volume and it appears to work. I'll let it play for a while and see what happens. It's been playing ten minutes already.
Alan, can you comment on what equivalent impedance each channel would see when driving this configuration?
However Alan's pre-amp suggestion is shrewd and will work if you have a channel to spare and are willing to play in multi-channel mode.
