Mcintosh mc-601 or 1201 ?

Depends on what you want to accomplish. The 601 and 1201 aren't very different in design, just power output. Doubling power only gets you 3 extra dB in SPL, but will increase control and depth noticeably. I'm not that familiar with the Dynaudio speakers, so I can't say if you will realize much improvement relative to the cubic dollars you're thinking about investing. Have fun and happy listening!

Check out the Audioaficianado Mcintosh forum. Lots of valueable information & comparisons.

The 601s are a great value for their level of performance and quality. The 1201s are a lot more money and the sonic benefit will depend greatly on your room size and speaker efficiency, large room and low efficiency speakers gaining more from the increase in power. The house sound is nearly identical with the 1201s providing more heft and bass control. Agree that AA has a very good McIntosh forum.

i read many years ago to hear a 3 decibal increase in loudness you have to triple your wattage, not double.

I believe the difference is not just watts... But I believe the 601 is quad balanced while the 1201 is not.

No double gets you only 3db more.  No more No less

i've read many years ago that to get a 3db increase in volume you would need to triple your current power. i remember reading this in the old "stereo review" magazine