Constrained layer damping tape on toroidal transformer?

Yes Agree that you should try a non conducting material to dampen your transformer.  If it does get too hot Sorbothane in a constraining package or pillow might do the trick.

I just got back my Ayre amp that the manufacturer  updated/repaired.  They put tape on the cooling  finds  and told me Ayre recommends it to reduce unwanted resonance.

I just bought a toroidal transformer for a project and it actually came with a foam mounting pad for isolation. I plan on gently tightening the mounting bolt so the foam doesn’t compress too much. Not bolting it down at all seems a little too risky.

Uh, the transformer is not “live”. I use mu metal to wrap transformers and trust me, mu metal is conductive.

Even if the transformer was “live” which it's not, you could wrap it with constrained layer damping tape since the non-conductive viscoelastic layer is the side that touches the transformer.

It is a fact that every transformer has a vibration characteristic, and it amazes me why the majority of manufacturers do not isolate these from the chassis. It is one of the most significant modifications of any piece of gear, whether it be amp, pre, transport, etc, and does enhance sq, ime. I have used roofing repair tape, such as Peel and Seal and USeal, Dynamat, and even mouse pads for this purpose, with a great outcome. Enjoy ! MrD.