I've owned the MA6500 for the last 2 months. I previously owned a Cary 300sei (300b 11-15 watt integrated SET) which I consider the best I had ever heard. The Cary replaced an Audio Research D-130 and LS-3 combination (also very good). My room is 12 x 12 x 9 high and I wanted to use Spendor s3/5 speakers (84 db/1 watt/meter) The main issue with the Cary (or any tube amp) was the heat it generated in my small room. Therefore, I wanted to find a cool running integrated that didn't leave me totally homesick for the Cary.
I am totally happy with the purchase of the MA6500. It has more than surpassed my expectations. The synergy with the Spendors is fantastic. My three sources are CD, SACD, and FM (I purchased a used McIntosh MR-7084 via Audiogon) Human voice reproduction is important to me. This is an area where the Cary excelled. The 6500 gives me the same response to voice that the Cary did. You can recognize when human voice reproduction is correct. It just sounds right.
The 6500 with Spendors does this very well. The overall presentation is natural, nothing glares, nothing booms. Music has its natural flow, the annunciation of vocals is excellent.
I have not been able to hear the 6900. According to an email to me from McIntosh, the 6500 combines a c15 preamp with a direct coupled version of the MC202 amp. The 6900 uses a autoformer coupled version of the MC202. I would guess that the 6900 (because of the autoformers) would be a benefit with speakers that have a low or unusual impedence plot. It would also be more beneficial if you have need for more refined tone control. Only auditioning the 6900 in home would tell for sure.
But, I'll probably never find out. I'm very satisfied. After lots of upgrading and experimenting, I think I'm happy to keep what I have for a while.
