I have a receiver currently in my garage, it is rated for output like this: 2x100MPO, next line reads 2x50RMS@6ohm (I assume this is what I want to use for a value). I currently have a single speaker to each channel, the problem is the speakers are MASSIVE in terms of physical dimensions. I have an old insignia home theater system that the receiver went out on. Each speaker is rated at 30W@4ohm. I have 5 speakers and all 5 of them combined are less than half the size of a single speaker currently out there.
I would like to use at least 4 speakers from the insignia set to replace the big ones currently out there. I am thinking that if I wired 2 in series and tied them to one channel on the receiver I would be ok but volts and ohms are not my cup of tea. Paralleled would give me 2 ohms and I think would overpower my receiver. Like I said this is going in my garage so I don't need blaring loud music with crystal clear quality, just some moderate tunes while i'm wrenching. I don't want to toast my receiver.
When you connect speakers in series you will add the resistance together so in this case it will double since the speakers are the same. You should be OK with this. If you parallel them the resistance will half which would not be at all safe. If the receiver has speaker A and B terminals then you can connect them to both sets of terminals.