A reviewer wrote that his test pair didn't really open up until he switched from a 125wpc amp to a 300wpc amp. (I think it was Sam Tellig in Stereophile. His review might be online.) You might try a range of amps within the same brand and see if more power makes a difference. If you plan on using a sub, then this may not be much of an issue. IMO, based on a home trial, it's pretty easy to coax sweet, extended high frequencies out of the CDM 1NTs, but it may take considerable power to get their best bass response.