LP Record Cleaning Machine - Ultrasonic or Vacuum

I use both a Spin Clean and a VPI 16.5. Total investment for both was about $400. How much is an ultrasonic cleaner? $4k?. I would rather use the $3,600 difference to buy music, and you can buy an aweful lot of music for $3600!

Someone will have to prove to me that a cutter head can cut a more complicated groove into vinyl than a modern cartridge can read, given they are normally cut at the same speed they are played. Have there been any definitive tests on that issue?

My vinyl collection (about 3,000) goes back 50 years, and is still growing. I love finding great music for $2. My 1st RCM was a Nitty Gritty 25 years ago. Later I moved on to a VPI. Both did an OK job, but nothing close to what I am now experiencing with an ultrasonic. Not only are the LP's much quieter, but there is a significant improvement in presence and clarity. The thrill of finding my collection sounding better than new is priceless. $1.25 per LP is cheap!

Someone will have to prove to me that a cutter head can cut a more complicated groove into vinyl than a modern cartridge can read, given they are normally cut at the same speed they are played. Have there been any definitive tests on that issue?

The contact radius of a cutting stylus is several orders of magnitude smaller than the contact radius of even the finest playback stylus. Therefore, the cutting stylus can trace shorter wavelengths and finer modulations of amplitude than any playback stylus can follow.

You can't perform micro-surgery with a butter knife. ;-)

I use an 6L ultra sonic tank (from ebay) and suspend several records at a time in tap water with a mild surfactant. Then finish on my VPI cleaner using art du son. Quite laborious but the results are excellent, even on old second hand vinyl.
Some albums are virtually silent on replay, the background that is! the music is very clear.