AV Receiver recommends

Thx-333, the CM1s are nice speakers, but not very efficient. I would go for more power to drive them. I doubt 100 watts is produced with 5 channels driven.

kn

Hi Knownothing… I'm, a bit of a newbie audiophile so you might want to talk to me like a child. What do you mean more power? Coming from the AV Receiver? Like a more powerful AV? Doesn't the Marantz SR5010 shoot out 100 Watts per channel?

the power ratings on most mass market avrs are notoriously overstated, often deceptively so--an avr touted at 100w/ch may actually achieve that with only two channels running and/or with very high distortion. e.g. i had a yamaha 5.1 avr which claimed 90w/ch but in fact tested at 35w with 5 channels running. from my experience, only nad and hk actually rate their receivers' power output reliably. power ratings aside, you also have to look at the receiver's ability to drive challenging loads--i.e. speakers such as your b&ws which have much lower than average sensitivity, or speakers which have lower impedance benefit from an amp/receiver designed to deliver high current.

Shouldn't the Marantz SR5010 be able to power 5 B&W CM1's?

IMHO, yes, and will power them as well as any other receiver at that price point.

The power for the majority of a/v receivers are rated with only 2 channels being used, so when using 5 or 7, the ouput per channel will be less. The problem is that some drop in power much more than others. The SR5010 is replacing the SR5009, and both likely have the same amplifier section with some other features being updated. Here are measurements for the SR5009,

http://www.soundandvision.com/content/marantz-sr5009-av-receiver-review-test-bench#igvWdDSZH5RyTsYf.97

Rated @ 100w, measured 111.7w - 2 channels, 72.9w - 5 channels, 68.5w - 7 channels

Another poster seem to think HK was more reliable with their rating. So, look at this HK receiver at roughly the same price point,

http://www.soundandvision.com/content/harmankardon-avr-3700-av-receiver-test-bench#83IsGPgvYtsDGWwk.97

Rated @ 125w, measured 151w - 2 channels, 37.2w - 5 channels, 27.9w - 7 channels

Sorry, I'll pass on the HK. It is true that NAD does have a more reliable rating, and their receiver at this price point is rated at 60w/ch with all 7 channels.

Now, are there any better a/v receivers, absolutely, but at a much greater expense. Again IMHO, the SR5010 looks like an excellent choice for it's price point. The SR5009 got a great review, and it appears the SR5010 is just a more updated version of that receiver.