Slaw wrote:
" I forgot to plug in my Vinyl Stack after turning my 40khz US cleaner on for a 30 minute cycle. I was worried but could hear no damage."
I've also done this with a cheap Chinese US machine and experienced no damage. But when I forgot to engage rotation in the German Elmasonic machine, after 15 minutes at 37khz the record melted at the inner grooves along the surface of the bath. I conclude from this that the Elma produces much more cavitation action than some of the other machines.