Thank you for the kind words Jafant.
I wish I could say this was a pet project for me.
These legacy amps still command a good amount of cash.
If I could buy more of them I would but people know ML quality and hang on to them. I wouldn't touch a newer, recent, amp. You will not find one at bargain prices. You certainly won't find service manuals floating around. If I can't work on it I don't want to own it. I don't think any of the original innovators are involved with this line anymore either.
If I find a bargain I jump on it. For example I bought a pristine Adcom amp and preamp on Craiglist the other day for $100 with the knowledge that it was broken. With under $12 in mosfets and 2 caps, I brought them back to life. I jumped on it because it was a Nelson Pass design, I wanted to see it for myself and I knew there were service documents floating around.
My sensible side will not let me go too far off the deep end.
I am more of a practical enthusiast, improving those things I can get my hands on at a decent price.
As for my listening impressions: I primarily use this amp in a listening room that also serves as a recording studio. Yeah I know, over-kill! But even studio monitors with 10" drivers can present a challenge in an environment where the source signal can be very raw. I spend a lot of time in that room so when not behind my console the amp is pleasantly working in the background providing rich, room filling sound. There is something amazing about an amplifier that does not have to flex its muscle. It will produce complex passages with no effort ,especially on the low end. The 300 Series produces a very musical, non-fatiguing sound. Those that have properly working specimens will not let them go. Those that do let them go often regret it. The only group that remains pissed off at ML are those that have a great piece of gear but find it unreasonable to spend $1200 - $1500 to get it serviced. A lot of audio shops turn the repair work away because they know they cannot get support, service manuals etc.Those that are in that situation, walk away quickly and trade in for newer, hassle free options. I don't think it should be that way. Look at all the old McIntosh, Krell, Dynas etc that remain in service today. They are like that because the respective manufacturers allow their gear to live in infamy with proper manuals, parts channels, etc made available to the public. I wish ML had the foresight to take down the wall of silence they put up. For those who live in other countries, I challenge you to call an "AUTHORIZED" ML service center and ask if you can buy a service manual. I really want to believe things in the ML world may be different in other countries.