I have a set of M70 with Tulip Stands, P45 and S45-2 with Stands. I plan to do a 4 channel setup with my vintage Sherwood S7900a Receiver. I plan to replace the caps in the 2 sets of speakers that I keep. The caps for the S45-2 and P45 looks the easiest to replace correct?  To my ears and in my smallish office/stereo room the P45 and S45-2 surprisingly sound better than the M70s. The bass and clarity in the P45 surprises me. The S45-2 sound so big and open. This is my second M70s I've had, and maybe the room is too small for them....I think the caps in all of them have never been replaced. So, I'm leaning selling the M70s and keeping the P45 for the fronts and the S45-2 for the backs. Does that seem like a good move?  The M70 says 4 ohms so I'm a little worried about running a 4 ohm plus a 4-8 ohm speaker all at the same time. Is that a concern? The receiver is rated for 4, 8 and 16 ohms and has a 4 channel setting. Thank you for your input.