Well I certainly agree that you can never have too much power. The A21 will provide it in spades. But by the time you add the cost of a new P5 and a used A21, I'll bet your back to what a new Halo Integrated costs.
I would think the A23 is more than adequate for your CM10's that are 8 Ohm nominal with a sensitivity of 90Db. The seller was driving Diamond 805D's with it and those are 8 Ohm and 88 Db sensitive. The A23 puts out 125 wpc into 8 and 225 wpc into 4 with 45 amps of peak current. I can't imagine that kind of power not getting the job done.
But I guess you won't know for sure unless you try it - the price is right and you could probably resell it for the same amount. If you get the bass response your looking for, then you can keep it and smile about the money you saved.
Maybe the seller will let you audition it with the 805D's? Hope it works out for you.
I would think the A23 is more than adequate for your CM10's that are 8 Ohm nominal with a sensitivity of 90Db. The seller was driving Diamond 805D's with it and those are 8 Ohm and 88 Db sensitive. The A23 puts out 125 wpc into 8 and 225 wpc into 4 with 45 amps of peak current. I can't imagine that kind of power not getting the job done.
But I guess you won't know for sure unless you try it - the price is right and you could probably resell it for the same amount. If you get the bass response your looking for, then you can keep it and smile about the money you saved.
Maybe the seller will let you audition it with the 805D's? Hope it works out for you.