@wolfie62 Dogberry is right. US can’t cure abused records, but US gets the most from the records you have.
I run a high power lab unit at 80KHz, 2 records at a time. If you fill a low power unit running at 40 KHz with 10 records, you won’t get much cleaning.
Full disclosure: ESL system, air bearing turntable. I think I’d detect a null effect.
I got my 10L US tank in 1999, from a closed down lab where I worked. Made in USA, used for prototyping metals prior to engraving, chemical etching, coating, printing of SS, silver, copper, brass, bronze, gold alloy, gold-clad, titanium. My unit has digital settings for frequency and power: 36 kHz-100 kHz, 100 watts - 1000 watts. I tried many frequencies and power levels. It even does programmable frequency sweep cleaning.
So your ASSUMPTIONS about my unit are way off base! And BTW, US cleaning is far less effective on soft materials than on metals. So you can keep your assumptions to yourselves. You don’t have the expertise to be making the bad judgements that you’re casting out here.