If you have an amp with 8 ohm impedance and you want to hook up two speakers, can both speakers be 8 ohm? The way I understand it is you want the speakers to either be 4 or 16 depending on the wiring method. But can you use 8 ohm or will that harm the amp or speakers or just sound bad?
This speaker wiring explanation was helpful to me:
Page 15
http://cie-wc.edu/Series_Parallel_9_14.pdf