Yamaha Aventage RX-A1020 Needs some speakers

Very good advice from Paraneer, and look closely at the last page of the Home Theater article (HT Labs Measures). Compare the measured power against published specs from Marantz. Also, high quality amps generally quote rated power with all channels driven, not just 2 channels like receivers.

CAn you recommend some specic model numbers for the Odyssey, Emotiva, Parasound, Anthem, NAD, Rotel amps. I assume I need around 200 watts per channel. Do I need that power at two channel only or for all the channels in HT usage?

Stay away from Adcom

http://app.audiogon.com/listings/solid-state-hafler-p3000-power-amp-2013-04-04-amplifiers-19403

http://app.audiogon.com/listings/solid-state-parasound-2125-great-condition-x-4-2013-04-14-amplifiers-75165-waxahachie-tx

http://app.audiogon.com/listings/solid-state-bryston-3b-amp-2013-03-25-amplifiers-17356

http://app.audiogon.com/listings/solid-state-acurus-200-x-3-modified-3-channel-200-watt-ch-amp-2013-04-05-amplifiers-27262-high-point-nc

You probably don't even need 200 wpc but since we don't know how big your room is, we'll start here and work our way down.

Since you originally mentioned three channel amps, I will limit the discussion here. Some 3 channel amps to consider are:
Parasound A31, 250 wpc, $3000
Anthem MCA-30, 180 wpc, $2100
Odyssey Stratos HT-3, 150 wpc, $1550
Emotiva XPA-3, 200 wpc, $700

Any of the above will more than get the job done with your CM9's. Its just a matter of how much or how little you want to spend and the level of quality you want. Finally, with a 3 channel amp handling the critical front three speakers, this will leave your Yamaha RX1020 to act as the preamp/processor and also power your surrounds for HT usage. The Yamaha will be more than up to the task just handling surround information. Hope this helps - happy listening!

Room size is 18'x 26' with 14' vaulted ceilings, lots of glass front and back, wood floors and half of one long side wall opens to kitchen.