I found resonance source.
I take flashlight and start observe panels when plays... and I found this.
View attachment 22709
loosened tape on back side of panel. In both the same. When I push it tape stay glued but because of front panel I can't repair this.
I have nothing to lose. I can play music with fart on bass or send it to repair. Before I send it I try to repair but I need to take out front panel. After that I want to use rubber roller with little heat on glue and stay with some load on this place. After that put panel back and... we will see.
I read on MLO that people opened smaller panels, CSL should open the same.
Yes, they are profesionalist, they have many video from work, like here:
That would have been my concern too. I assume those big attractive metal cans enclose toroidal transformers. Maybe that's the secret. The specs say "Load Impedance: 8 and 4 ohms", which is not very meaningful (damping factor?). My experience with tubes driving CLS II's was not satisfying, rolled off treble. But they were just classic Dynaco E-core transformers.Before I bought it I afraid impedance drop and high capacity of CLS but Ayon drive it without problems.
Hi.It's difficult to tell what I'm seeing in the circled area of your photo.
It is tuning tape. It is glued to the rear stator on inside surface by Martin Logan. I have early model with first type of transformers and PCB. It is standard adhesive tape and after few years dust sticks there.