Your favorite Electrostatic, Panel spkr

faxer, those look like someone from Apogee decided to start his own company. The construction is very similar.
select hifi, If you have not already put some acoustic foam tiles on the wall directly behind the panels. I would think 2 wide and 3 high. They are 12" tiles. This will cut the reflection of frequencies above 250 Hz and usually improves the image quite a bit. There is no reason that they should not image as well as the Apogees. You would think better as there is no crossover.  https://www.parts-express.com/sonic-barrier-fwp122-studio-acoustic-foam-wedge-panel-12-x-12-x-2-black-12-pack--260-547
jdl57 driving those with ML-2s is brilliant. Those are some of the best sounding amps ever made. John Curl designed them, they are straight class A and the shoot way above their power rating. Some people think they switch to AB and keep going but Mark Levinson himself denied it. I think the question should have gone to Mr Curl. That fact that they are going after all these years speaks highly of their construction quality.

Actually, I was reading a post a while ago on DIYaudio.com. It was about the power switch on the ML-2. John Curl answered it and stated that he was not involved in the final layout of the ML-2, he had worked on the project however. Tom Colangelo is credited with the design of the ML-2. I do have a Vendetta Research phono stage however, that was all John.

I first heard the ML-2 around 1980, powering a pair of Magnepan Tympanis. I never forgot that experience. After building my big horn speakers that I talk about elsewhere, I was no longer satisfied with the sound of my Sound Labs. It was then I discovered that the ML-2 was designed specifically for electrostatics, specifically the Quad ESL 57. They are large, heavy, draw 400 watts at idle, and with 400 watts to make 25 watts, you can rest assured they are 100% class A. All of my amps are Class A. They are about 1/2 heat sink by volume, so they don't really get all that warm. I also have a British Fidelity A-1 integrated, another Class A amp that people say is not, and that little darlin' gets HOT. It pulls about 180 watts to make 20, but it does not have the current capability of the ML-2.  I found a pair, and yes a lot of caps had to be replaced, but they are every bit as magical as I remember. They returned the Sound Labs to the top of my favorite speaker list again. Actually, I think that is a testament to how well my horn system turned out. It is essentially an Altec Voice of the Theater system with a ribbon tweeter added. And, yes, it is time aligned.

select-hifi, the tiles are dirt cheap. They are very light. Just one drop of high viscosity cyano acrylate glue at each corner will hold them up. If you put them up alternating the direction of the fins they look pretty cool. Lay things out carefully before you get started. I used a plumb line to make sure I got everything straight. Please let us know how it goes.

Mike

jd57, you learn something every day. The last time I saw ML-2s was around 1979. There were 6 of them driving the HQD system. That store supplied me with components for my clients 10% off and my own stuff at salesman's comp. Anyway, the HQD system was a nightmare and not many were sold. It was not because of the amps but Quads and Decca ribbons blew all over the place. They sounded great and people tended to crank things beyond the power handling capability of the speakers. The only other dependable components were the Hartleys.  Very few people had a room big enough for them.