Good luck. I spent a lot of time and effort trying to find out the differences between the MA9S1 monoblocks and the revised version, the S2. I concluded, with no help from Marantz or my local dealers who were clueless, that therewere in fact almost no differences except some capacity was added to the power supply. Therefore, I chose to buy the older version at a savings of $2500 to $3000 and frankly, the sound is superb. My take is that I would start with the older model and see if you like it.
Difference between Marantz PM-11S1 and S2
Can anyone explain the difference between these two versions of the Marantz integrated amp? Both can be had on the 'Gon with the S2 being almost 2x the price.