KLaudio ran tests with yellow colored vinyl where they ran records through the system for very extended periods of time with no yellow colored residue in the tank. You are looking at the record residue gunk taken out.
I've had the Klaudio ultrasonic since 2013. Previously a Loricraft which I use only for extremely soiled records.
The KLaudio sound quality is incredible with lower noise floor, nearly all pops and ticks gone, enhanced low level details, better separation of instruments and more refined tonality.
Many used "first pressings etc" that I buy typically are brought up a "play grade" or two and the cleaning of new records makes a big difference too.
I know my records well and have never heard any degridation in sound or high frequencies from The ultrasonic.
My cleaning area gets late afternoon sunlight where you can clearly see dust on what looks like a good record going in and a perfect record with no dust going out.
Also with the KLaudio there is almost never any static associated with records
The best thing?
Load an lp, go about your business, sleeve it, load next lp
It's not labor intensive.
Spend your time listening
Read more at https://www.analogplanet.com/content/if-charles-kirmusss-record-cleaning-machine-and-regimen-correct...