I recently started a project to build an inexpensive speaker/amplifier that is portable enough to take outside easily. I purchased a center-channel speaker from a thrift store for $6 and an amplifier for $25. I would like to combine the left and right channels so that both channels are represented in the output, but I've read conflicting information about whether this will damage the amp and/or speaker if I do it at the speaker level.
Right now I just have an RCA y-adapter to combine it at the line level (which works fine), but I was thinking it might work better to combine it at the speaker level so I can get more volume. The amp pushes out 20 watts per channel, and the speaker can handle much more than 40 watts.
Is it safe to combine the inputs at the speaker level? Can I do it without much additional expense?