Rotel RMB-1575 a good match for B&W CM10's?

@caphill - I was talking about the RMB-1575 that the OP currently owns and that we have all agreed is Class D.  I'm sure that the 1585 that is Class AB will be highly superior.

The Rotel RMB-1585 (class AB) isn’t based on older class AB design and is very capable amp and can handle low impedance loads with ease. Very dynamic amplifier with massive headroom. Dynamically it is on par with the Classe Sigma Amp5.
The Rotel RMB-1585 is huge very heavy and has two over-sized toroidal transformers main power supplies stacked up.

Classe uses its own proprietary class D design for their Sigma series amplifiers and wasn’t based on nCore Hypex module design. True, if I have the choice to choose between Classe Sigma amps (class D design) and Classe’s own class AB or class A designs (Delta series), then of course I will go with their class AB or A amplifiers but they are lot more expensive than their Sigma series amplifiers (class D). And Classe Delta series line have been discontinued last year and the new upcoming replacement Delta series products will be introduced either later in the year or next year and the their new Delta series amps will be class A design and they will be introduced soon. I had a chance to hear pre-production run of their new upcoming Delta Pre stereo preamp/DAC and a pair of their new upcoming Delta Mono monoblock amps (class A design) paired with the B&W 802 D3 speakers and they sounded spectacular together. But I was told that the retail price for their new upcoming Delta Mono monoblock amps will be around $20k and $10k for their new upcoming Delta Pre stereo preamp/DAC. 
Classe finally gets back to its root making class A design amps with their new upcoming Delta series amplifiers.

I agree that for listening to music I prefer class AB or A design amps to class D amps but for home theater class D amps would be fine.

Ok thanks, I think I need to find some showrooms and listen to some different amps before I make any decisions.

In regards to class D amps lacking bottom end oomph......imo not all class D amps perform or sound the same. Class D amps or digital amplifiers have come a long way and the class D or digital amplifier technology have greatly improved over time. If it was 20 yrs ago yes class D amps were inferior in comparison to analog (class AB or A) amplifiers. Don't hesitate about going class D nowadays. Especially these high end brands like Classe, Bel Canto, Theta Digital, etc make excellent class D amps. 

That being said, I highly recommend the Classe Sigma Amp5. The Sigma series is Classe's entry level series. It is a step up sonically from the big Rotel RMB-1585.

But the RMB-1585 is a great amp too especially considering its asking price and was built like a tank. Actually the Rotel RMB-1585 runs cool. Comes with 2 fans placed toward the back panel and the fans is barely inaudible. The internal heat management is superb with this amp. No matter how hard you drive it the amp will never get warm or hot. 
The sound is very fulsome, fluid very musical very smooth and has full midrange bloom  and has a bottom end grunt you desire but I found this amp lacking a bit in extracting all musical nuances and information, details, transparency and resolution in comparison to the Classe Sigma Amp5. 
The tonality is leaned towards the warm side of neutral. The RMB-1585 has a level of great warmth that people desire especially for listening to music. 

The Classe Sigma Amp5 however sounded more resolved, cleaner, faster with much better details, transparency than the Rotel RMB-1585. The Classe Sigma is a lot more revealing sounding amp without sounding harsh or bright and the Classe Sigma Amp5 excels in extracting all musical nuances details and information and with greater drive, rhythm, pace, timing and speed than the Rotel RMB-1585. It sounded clean, fast with more solid accurate imaging and greater soundstage than the Rotel. The imaging and soundstage is vast with 3D like. Overall the music or movies sounded and felt more alive with the Classe. Everything is popped with the Classe whereas with the Rotel as if there's haze blanketed the soundscape and things become more obscured whereas with the Classe everything becomes more solid and obvious. 

But the Classe Sigma Amp5 is a very revealing amp and will reveal the weaknesses of the source such as bad recordings, and qualities of your upstream electronics eg preamp/processor, source component (player), DAC, etc. It also reveals the weaknesses of your cables and speakers qualities. Make sure you get the good quality and the right cablings (speaker cables, interconnects, power cables, etc). And I wouldn't recommend using your Pioneer receiver as your preamp processor as the Classe Sigma Amp5 isn't forgiving of the source and quality of upstream electronics eg preamp, processor, etc. As your budget opens up more later down the road I would recommend that you upgrade your preamp processor and source component (player, etc). 

Thanks for the advice, this was my only concern having read up on Class D vs Class AB, from what I’ve read they have a tendency to lack low end ooomph vs AB amps.

I just upgraded to the CM’s at the front so I’m currently driving them with a Pioneer SC27 receiver so this is clearly the weak link in my system now. I simply don’t have the cash to buy an new amp and processor so the first step is a new amp and continue using the SC27 as the processor, but eventually move to a standalone processor.

Looks like I need to rethink, I could put a 1585 inside a cabinet, I presume this would be ok so long as there’s lots of space around it for cooling?

Thanks again!

I wouldn't get the RMB-1575 as it is a class D amplifier. Rotel is very well known and very good for their analog amplifiers (class AB amps). I would highly recommend the big RMB-1585 amp. 
It is a spectacular amp especially for the money. Rotel class D amp such as the RMB-1575 isn't that great. The RMB-1585 is far superior sounding and performing amp compared to the RMB-1575 (class D amp). 

If you want to get something small compact in size (class D amp) I would highly recommend the Classe Sigma Amp5 five-channel amp, which is class D but sounding spectacular very smooth analog like sounding amp. Highs are smooth, fast, clean very transparent sounding amp. The Classe Sigma Amp5 retails for $5k. It is very compact in size and light weight. Classe uses its own proprietary class D design. Uses high current switching design with power factor correction (PFC) and it uses DSP to regulate the switch mode. 

What is your preamp processor? 
Classe also makes Sigma SSP av preamp processor to go with the Sigma Amp5 and will be a great match when paired together. Couple yrs ago I had a chance to hear the Classe Sigma SSP/Sigma Amp5 combo on the B&W CM10 S2 speaker system at my local dealer and they sounded fabulous together. I've heard it mainly in stereo when listening to stereo music but had a chance to try it out in surrounds for home theater (bluray movies). The Classe Sigma SSP preamp processor is optimized for stereo performance for stereo music playbacks or when used as a high end stereo preamp. 
If you prioritize or value stereo music playbacks then the Classe Sigma SSP will be your perfect one box solution.
You won't need a separate dedicated high end stereo preamp with the Classe Sigma SSP in your setup. 

Hope this helps.