Thumbs up for ultrasonic record cleaning


My Cleaner Vinyl ultrasonic record cleaner arrived today and it’s impressive.

Everything I’d read indicated that ultrasonic was the way to go, and now I count myself among the believers. Everything is better - records are quieter, less ticks and pops, more detail etc.

All my records had been previously cleaned with a vacuum record cleaner and were well cared for. Nonetheless, the difference is obvious and overwhelmingly positive.

Phil
phil0618
@fleschler- You have it backwards. A higher frequency US will have lower energy release and it will be much more evenly distributed than lower frequency. The cavitation bubble size is inversely proportional to the frequency; the higher the frequency, the smaller the bubbles and the lower the energy release when they collapse. The smaller bubbles are also more effective at removing smaller particles than larger bubbles (lower frequency), especially between the grooves. The Kirmuss RCM is closer to an industrial cleaner and should be avoided IMHO.

Higher temps facilitate cavitation and will increase the energy release, which may not be desirable if you are worried about damage. Adding surfactants and IPA will also increase cavitation. Whether this is advantageous or not depends on frequency, power, chemistry of the bath, distance from the transducers, volume of the tank, coupling efficiency of the transducers and matching of the drive signal for both impedance and frequency of the transducers.
I've purchased ebay records where the seller used the KLAudio.  The records are nearly mint; however, they are missing their highs.  Multiple copies (I've given six of them as gifts cleaned on a VPI 16.5) of the AMERICAN PERCUSSION SOCIETY PRICE URANIA have all got fantastic highs but the KLAudio cleaned copy is like someone filtered off the highs.  This is the third ebay US cleaned record I received sounding like the highs are missing.  A friend has the Audio Desk and mentioned that the KLAudio shoots the cavitation directly at the disc versus below the disc surface and wipes out the highs.  Kirmuss Audio claims the higher frequency and temperature can both harm the highs and warp the record.  Why take a chance on higher than necessary frequency and higher temperatures if reducing them is safer?  
@dgarretson

I prefer the 80KHz setting because of the graph of cleaning efficiency vs frequency on DIYAUDIO, although I cannot say that I’ve found a reliably detectable difference. Just a theoretical one!

The big thing is that the wavelength is much smaller, so that there is plenty of room for the wave to develop on all sides, so no disappointing surprises when you play that record in 6 months time. Also, 80KHz is quieter. And as you note, it doesn’t heat the chemistry up as much. Me lazy.
@fleschler 
You say, "I think your method of US is using 10 C degree too hot water and 100% too high a cavitation frequency. Maybe that’s why you can’t hear the difference on 3-6 posting; however you state you did see and hear the difference using this method on 2-6 post."

The one posting was about a routine involving 2 records at inadequate spacing, temperature, and rinsing. Improving these helped. The other posting was an experiment to explicitly test the hypothesis that one record would be damaged (it wasn't).

The differences were: more energy per record and very high temperature on one sector of the record in the test, higher temperature on the bulk of the record and better rinsing for the routine cleaning. Don't quite see how you conclude that 45C is too hot and US frequency is 100% too high. Also, don't quite see how this explains the results.

Cleaning efficiency vs frequency is graphed on the DIYAUDIO thread, if you are interested.
@whart That's what I thought - KL discourages use of any add-ons no? Honestly, I'm sticking with alcohol just by some inertia. I like it for its grease dissolving properties. Also as far as I understand, it actually makes the 40kHz cavitation gentler by lowering  water's surface tension. Having said that, next tank solution I'm gonna try will be just water + 0.05% Tergitrol, excactly as used by the Congress Library and see if I get less clicks n pops. I also tried pure water US but I'm a bit afraid it may be too aggressive
plus I like the Tergitol solvent properties.


@bydlo - i have not added any surfactant/detergent to the water since I’ve been using the KL. When I got it, I was using Reagent Grade 1, which seemed to be a waste of money. Now I just use distilled in the US, but for a finish rinse on valuable or challenged records, I’ll use the Reagent Grade 1 and vacuum on the Monks. As mentioned, when the KL goes, my plan is to try a DIY approach, largely b/c of the feature set, which includes the ability to use a surfactant to enhance cavitation effect.
For now, I just change out the bath water every thirty records, even though most of them have been precleaned. (Yeah, I’m a little compulsive, but I don’t have a filtering system hooked up to the KL).
Not to open a can of worms- I think this was discussed earlier in this thread- but the idea of alcohol and ultrasonic makes me a little nervous. I gather most of you are using only a small amount. Since I haven’t mixed any chemistry for ultrasonic, I can’t contribute to a meaningful discussion about what alcohol adds. I know in the old days, using vacuum, alcohol was commonly part of the cleaning fluid. I don’t think it is a terribly good solvent. Perhaps it is the evaporative properties. (I’m not concerned about damage to the vinyl since I think the exposure to the plastic is limited, but the flash point does concern me). Maybe I’m a nervous nelly.
There have been some good suggestions here on different chemistry. I use an lab grade detergent to clean my lab dishware which can be used in an ultrasonic machine. It isn’t very expensive. 1 part per 100 or 200 is recommended. It foams like crazy when I am hand washing the various glass I use hold brushes, and mix one of my RCM fluids (Hannl concentrate, which I dilute with the reagent water).  
I think there's a little Walter White in all of us. :)

@whart Thank you very much for your informative input! This is similar to the process I'm currently using, but I do not rinse after the vac pre-wash since I US clean with the same solution as I vac (5% IPA + 0.05% Tergitol).
What do you use for your US cycle? Just high purity water?

@whart - Thanks for your thoughtful response. The general consensus seems to be that US RCMs do not cause any damage; I suspect that if any microscopic changes (damage) are occurring, it is subtle, random, isolated and cumulative, possibly evading detection via listening tests for several cycles.

I also suspect that given the number of variables, the amount of cleansing action (and by extension, over cleaning and possible damage) varies greatly with each application. I doubt that damage would be heard as an average degradation across the entire LP, but would be random and very limited until it became severe enough. My thought process is to better understand the mechanics of US cleaning in order to optimize the cleaning process while minimizing the potential for damage. My impression after reading this thread (and others) is that few people using these devices fully understand what is occurring and are relying on mfrs specs and hoping for the best. My impression of the electronics driving the KLAudio transducers is that of a very simplistic approach, adjusting one important parameter (frequency) in order to obtain a desired specification (power) without fully optimizing the process.

Some of the industrial tanks vary the frequency and therefore the power to create "waves" of transmitted energy to improve the cleaning process. While the average power may be 150W, the peak power could be many times higher. The KLAudio machine maintains constant frequency, but the DC supply to the output transistors is essentially unfiltered rectified line voltage so the transducers "pulse" at 100/120Hz with peak power ~280W.

FYI, I use both IPA and surfactant (tergitol) in my KLAudio RCM for the past 2 years. I know it voids the warranty, but so far, I have not experienced any bad side effects.  I also vacuum the records after cleaning with an Okki Noki.
@gbanderhoos-you raise some interesting points, starting with the actual operating frequency of your KL. I wonder how much variability there is among units in the field?
We are told that 40Khz doesn’t cause damage, at least for relatively short duration at fairly high rotational speeds (AD, KL); most of the DIY set ups seem to rotate at a lower speed, and for longer cleaning times, no? (I have only owned the AD and KL, but am aiming for a DIY when the KL goes, mainly for operational flexibility rather than low cost). I prefer point nozzle vac drying to forced air or passive air drying since I think it does a better job of removing the vestiges of contamination and fluid. I learned pretty quickly that the commercial US machines intended for LP did not clean challenged records that could get clean using AIVS No. 15, some vigorous agitation, pure water rinse, sometimes repeating the process, and then employing the US, with a final rinse and vacuum using high purity water.
I pre-clean any used record (and a few new ones that are obvious dirty) before going into the ultrasonic, using a Monks, and high purity rinse. I only find a deposit of very fine grit in the KL tank from new records that have not been pre-cleaned.
As for damage, I suppose you could test using a blank LP, examine for pitting, etc.-a point raised by a vendor of new cleaning service who opted for 80khz transducers run at low power (Perfect Vinyl Forever, who has recently been posting about his equipment and methods on various fora).
I’ve certainly heard no evidence of damage, which would be one good way to discern--most revealing to me are the results I get from a record cleaned both by conventional (fluid/vacuum/rinse/vacuum) and US, sometimes repeated conventional cleanings using AIVS No. 15 and reagent grade 1 rinse--where the record initially exhibits low level noise, raspiness, tracing distortion-often associated with groove damaged records. These can in many cases, not all, clean up to be quiet players. Once I clean a record using combined methods and it plays well, I don’t re-clean or do follow up re-cleans.
I’ve also had records that I cleaned decades ago using a VPI and who knows what fluid at the time (I tried several including some home brews) that play beautifully today.
I’ve also been reliably informed that using a surfactant in the US enhances the cavitation effect dramatically. Perhaps using a surfactant reduces the need for lower frequency, higher power and reduces the potential risk of damage, I don’t know. I found the earlier AD to be kludgey in operation, the KL of course doesn’t permit the use of additives as far as I know, thus my aim for a DIY which permits use of a surfactant.

@bydlo After many cleanings, I’ve set aside a few problem records for continuing experiments. Some of these were improved after transitioning from ISO to Versaclean. The 80kHz cycle didn’t seem to make a difference, though I like that its reduced power doesn’t increase the bath temperature as fast as the 38kHz action.

As long as you don’t allow the LP to sit still in the bath, don’t be afraid of cleaning at 45C. I’ve had some luck spinning problem LPs in the hot tub for an hour or so at 45C prior to engaging the pulse cycle. It’s likely that the vinyl expands and contracts repeatedly as it spins in and out of a hot bath, loosening debris over time that is then pounded out during the subsequent pulse cycle.

However, after all is said and done, some clicks and pops are deemed record defects. As a general rule I give every new record a cleaning, on the theory that it is better not to grind in debris with even a single pass of the stylus. However, I’ll usually pass on the pre-cleaning with MoFi and Analog Productions-- and with impeccable pressings like Rhino’s recent Donald Fagen Cheap Xmas box set.

gbanderhoos
I replaced it with a KLAudio KD-CLN-LP200 with (IMO) much better build quality, but still unimpressive results ...
That’s interesting. I’ve had outstanding results with the Klaudio. It may not be the best device for extremely dirty LPs such as you might find at a yard sale. For them, I think the right fluid and a vacuum machine might be the best first step. But for everything else it works very well, imo. What could be more impressive than a pristine clean disc?

... how does one know what they are really doing to the record surface (not only whether it is effectively being cleaned, but whether it is being damaged in the process)?
If the record looks clean, and the phono cartridge stylus is clean after playing the LP, I’m satisfied that the US cleaner was effective. Because LPs almost always sound better after a cycle through the Klaudio, I can’t imagine how the cleaner could have caused damage in any way. The few LPs I’ve heard that may not sound better after being cleaned in the Klaudio were clean to start with. They sound about the same after a pass through the Klaudio.
@dgarretson Very interesting observation re 38 vs 80kHz! Have you made some systematic research on it? There is quite some discussion re frequency going on. You input would be very valuable.

At the moment I'm afraid to go past 35C and 15mins. If I have a Lp I can sacrifice, I'd try.


With persistent clicks and pops, I don’t find that the 80khz setting on my Elmasonic P improves on a 38kHz cycle. Try 20 minutes at 40-45C and 100% power, with a 1:30 concentration of Fisher Versaclean instead of Iso.

Some records with stubborn clicks and pops just won’t clean up. Sometimes the pops seem reduced in amplitude.

I’ve been following this thread for some time now, very interesting reading and thanks to all the contributors.

Some observations:
I owned one of the original AD US cleaners and was not impressed with the results or the build quality. I replaced it with a KLAudio KD-CLN-LP200 with (IMO) much better build quality, but still unimpressive results. I’ve looked at the DIY machines and have been reading everything I can get my hands on wrt to US technology. There seems to be a considerable difference between low frequency US cleaners (28kHz) and higher frequency (80-100kHz), the former used primarily as industrial cleaners (car parts, large metal components etc), the latter used for more delicate structures, especially fine jewelry. The cleaning action is created by the collapse of the cavitation bubbles which can create extremely high pressure (10’s of Mpa) and high temps (5000°C), but on a very small scale, determined by the size of the bubbles: The lower the frequency, the larger the bubbles and the more concentrated the released energy. On high power, low frequency US machines, this process can be so aggressive the sides of the stainless steel tank are subject to etching.

I was curious about this, so I did some measurements on my KLAudio RCM which is assumed to be 40kHz. It actually runs at 34.72kHz which would seem to be more aggressive, almost midway between 28 and 40kHz. There was a frequency adjustment pot, and I monitored the AC power being consumed as I adjusted the pot. Increasing the frequency lowered the power consumption and lowering it increased the power; at 33kHz, it went from 200W to almost 350W. The power consumption also changed drastically between running the cleaner with and without a record (200W with vs 150W without) indicating that the load seen by the transducers affect power consumption and the load changes with mass, density and distance from transducers.

So my question is this: With so many variables affecting the performance and operating parameters of the US process (temp, surface tension, power, frequency, cavitation efficiency), how does one know what they are really getting and what they are doing to the record surface (not only whether it is effectively being cleaned, but whether it is being damaged in the process)?
As a follow up, directions I'm considering:

*80kHz tank since I use it as the 2nd stage and 80kHz process is more penetrating but gentler
*slower motor; anyone knows of a cheap 1/3rpm or so motors in EU? 230V synchro would be the best
*submicron filter - are carbon filters good? would they not filter out also the chemical solution out of the water?

I've been experimenting with USC in the past few month, having cleaned about 30-40 2nd hand classical Lp's so far. I've added USC as a second stage after my regular Okki Nokki vacuum cleaning.

I must say it has not been so far such an epiphany to me as it seems to others, rather incremental. The biggest disappointment is that it does not seem to reduce clicks&pops, sometimes making them even more pronounced, probably due to quieting the background. I'm quite sensitive to clicks as I'm listening on high efficient Stax headphones, so all is in my ears.

Whats it does seem to do, provided I use right chemistry (see below), is  increase of micro and macro dynamics, and detail retrieval (so perhaps all the clicks I hear are due to permanent vinyl damage). On some LP's the sound becomes more direct which is a big plus for me.

Here is the hardware and procedures I use:

GT Sonic 6L 150W 40kHz machine + 1um filter+ 1rpm motor for rotation. I clean at most 3 Lp's at the time as evenly spaced as possible. I can clearly see the standing waves between the vinyls.
Currently I'm using 5% IPA + 0.05% Tergitol S7, which is available in Poland albeit v expensive. This Tergitol concentration is recommended by the archivists and the solution is already foaming. I was afraid to  use the higher 0.13% concentration as recommended elsewhere after my failure with PhotoFlo. I used it instead of the Tergitol and it was giving me unpleasantly "plasticky" sound despite a mandatory 2 step rinse on the vacuum machine. Had to US rinse all vinyls I cleaned with it and clean all that had contact, incl. the tank, the filter, brushes, etc.

The procedure is:
*1 step vacuum: Apply the above solution, let it soak for 5mins, biderectional scrub, vacuum.
*USC: 60% power 40kHz, 32-33C, 15mins (first degass for 10mins, filter before the batches)
*2 step vac rinse: First high purity DI water then 3% ethanol

I've once heard opinion that alcohol dries vinyl surface and one can never get rid of pops&clicks. I tried just DI water USC too but no real change and Tergitol softens the cavitation action at 40kHz, lowering the surface tension. I'm thinking of investing in a second 80kHz tank to see if the more refined cavitation would improve. Perhaps my initial vac + scrub is quite efficient in removing what's easy to remove.

Cheers,
b






I built my own cleaner on the design of a drive thro car wash system. I am a aero modeller/flier so have lots of servos/materials and tools.

Its basically a rectangular tub with a horizontal spindle and lock for the record disk. I have two (one for each side of the record) high pressure jets (tubes of aluminium drilled with tiny holes) to blast the surface of the disk. The lid of the unit covers the disk to the lower part of the label so it doesn't get saturated (after bit of experimenting and lost labels later). I pump distilled water under high pressure to blast the grit and muck from the record for 2 minutes and then the timer servo switches off the water and then blasts filtered air for one minute the dry the disk surface.

A second timer signals the procedure is finished. No chemicals, no mess other than to empty the drain tank underneath when a float contact says its full. The whole cleaning blast area is 1/4 the record area. They come out nice, clean and dry. Amazing what a bit of tinkering will do and watching drive through car washers.

I have about 25,000 LPs.  I've noticed that the LPs I cleaned 20 to 30 years ago using a stiff brush and Torumat fluid on a VPI 16.5 sound as good and clean as when I first cleaned them.  I'm playing them on a VPI VI/SME IV (mod)/Benz Ruby 3.  No increase in surface noise even after 100 playings of several of them.  Clean stylus and clean records make both last a long time.
I noticed that the Rushton cleaning method also limits the water temperature and the cavitation frequency.   It could be that his solution is important for better results.  This is an experiment I'm willing to try.  He also uses a VPI 16.5 to dry as I would.
I like the Kirmuss Audio cleaner because it uses a lower frequency (35Khz), lower temperature (95 degrees), common fluid (distilled water and a touch of alcohol), proper spacing for cleaning (Cleaner Vinyl Pro stack doesn’t permit cavitation bubbles to enter deep between records), does shellac 78s and 45s as well as 2 LPs at a time and cavitation to occur beneath and away from the records (not blasted at the surface like one $4500 machine). It doesn’t have scrubbing felt/brushes or other surfaces rather just a slight grip from lips to hold the record in place while it spins. It’s $800 for a fully finished machine. It does not dry but also doesn’t add static or dry dirt back to the surfaces.  Plus, the low cost of water/surfactant allows for no filtration and just refilling after a dozen washes.

Terry9-I think your method of US is using 10 C degree too hot water and 100% too high a cavitation frequency. Maybe that’s why you can’t hear the difference on 3-6 posting; however you state you did see and hear the difference using this method on 2-6 post.
@dgarretson ,

Let us know how the tergiclean vs. Versa-Clean works? Please?
@terry9,

Sorry for the delay. In terms of SQ, I cannot tell a difference. I do steam beforehand. I think my heroic pre-clean method needs to be a factor in my posted results here. I believe your "heroic" rinsing is still a big key in SQ after a US clean. I doubled the Versa-Clean after I wrote the post above to my latest water. I have not noticed any SQ differences.

After adding the Photo-Flo, I noticed a completely dry record after lifting it out of the bath and letting it spin for a very short time. I feel trying the additional steaming after the US cleaning is a waist of effort. I get a better SQ result from a warm rinse from my kitchen sink tap water/sprayer , then a rinse of distilled water, then a final distilled water rinse/vacuum on my VPI 16.5, the a De-Stat.

@bdp24 ,

I guess the appropriate discussion for music is elsewhere, but I agree with MF regarding the SQ= around an 8 on the PC lp which is alright.
Thanks for mentioning the Versa-Clean. I just ordered it to compare to the mix of Everclear and Photo-flo that I’m using in my Elmasonic P. After a 20 minute ultrasonic bath I rinse/vac with distilled water and TergiKleen on a VPI 16.5. This evacuates and dries the LP so well that I don’t feel a need for more rinsing or steam.
@slaw 

How does the 1:120 work (vs 1:40)? I have not tried it at lower than Fisher's 1:40 recommendation.

I do not use photo-flo. My goal is to leave nothing whatsoever on the surface of the record.
AFAIK, I have never reviewed or commented on the Benchmark DAC in Stereophile.
I apologize Kal. In fact, I pledge not to diss on your rather unique (for Stereophile) perspective or to use your name in derogatory fashion in the future. Your viewpoints on audio could nor possibly differ more than my own and as a result, I make careless mistakes like this one. I need to move on an not single you out. That said, on a wine board that I regularly frequent, someone enthusiastically recommended the Oppo UDP205 as a CD spinner based on your blurb under "Recommended Components". I find this unfortunate. I believe that any recommendation has to take into account longevity and build quality, something that seems to be a non-issue in your assessments. But there I go again. I will move on from making you a boogieman. 
Ooh slaw, the MFSL A Salty Dog! One of my long-time favorite albums, I have owned the British Regal Zonophone pressing from the time of the album's release. How does the MF sound? Have you heard a Regal Zonophone for comparison? Great sounding album!
@terry9,

I just changed to brand new distilled water. The closest I can measure, I’m using 256 oz. in my tank when it’s filled properly. I put in 2 oz. Versa-Clean, & just slightly over 1 tsp. of Photo-Flo. The first lp I’m cleaning is a brand new Procol Harum "A Salty Dog" MFSL. My settings are..40 minutes / 45 degeees C / RPM = 1 revolution every 7 minutes.. This is a much lower ratio than you suggest...closer to 100:1. I do steam first with the Audio Intelligent down with dirty concentrate. At this ratio, great rinsing is still needed.

I forget,, do you use Photo-Flo in your mixture? For right now, my heroic rinsing is another steam of the lp after a US cleaning. That’s pretty "heroic"!
fsonicsmith wrote:
I apologize for digressing, but JA and his buddy Kal Rubinson still insist that Benchmark DAC's are among the best and yet consumer after consumer on the various audio Boards express their regret for having bought one.

AFAIK, I have never reviewed or commented on the Benchmark DAC in Stereophile.
This discussion, has been most helpful for me.

I only hope others will find it in a similar way.

Thanks so much to terry9!
You may find this explanation of different purification processes helpful:  [url]http://www.emdmillipore.com/US/en/water-purification/learning-centers/tutorial/purification-techniqu...[/url] The source is a manufacturer of equipment used in labs and hospitals.
In my interview with the LOC, the preservation specialist suggested the D/I was sufficient for records, the main objective being to remove mineral content. 
I've been told you can buy reagent grade II at places like Cosco. 
The reagent grade 1 cannot be shipped to a residence. It's also more costly. I now only use it to mix fluids and for rinse steps on the Monks. I used standard supermarket distilled in the US machine. 

Another way to describe how much of an improvement this has made...

I have, waiting for me around 30 newly purchased lps.
I'm finding myself gravitating towards my older lps to hear them like I've never heard them before.This is on my (free day)!

How's that.........?
@slaw 

It depends. First on the quality of distilled water (which is standard), and the sample of RO water (which is not).

If I were doing that measurement, I would try an instrument called a 'megger', which typically reads resistance with the help of a high voltage supply. Since I don't need one, I don't have one, and just bite the bullet and buy pharmacy distilled at $1.50 a gallon. Lazy? Yeah - but that's just me.
@terry9,

How does distilled water compare to de-ionized water in this realm?

I’ve read on various threads about a measuring device for mold an so on...I ask because if there's an inexpensive device that might be able to help us determine with more accuracy, a water change in out US cleaners?...  Do you have any thoughts on this?

Thank you.
@slaw 

Thanks for posting your experiences. Glad it's working for you! I am sure that it will help others to achieve better results.

As for your RO question, I think it is a good one. I used distilled because it has very low concentrations of dissolved minerals, which could conceivably deposit on the record while drying. Dissolved minerals can be measured by conductivity, which is very low for distilled. Specs for RO are harder to come by, and depend on system maintenance, etc.
@terry9 ,

After re-reading my last post, I realize it was unnecessary.

I had asked you earlier if you could ascribe the positive benefit of your cleaning methods (filtering/rinsing/fluids) over what I was doing. You said around 50%. I was skeptical. I am no longer. Just using the Versa-Clean in my current water and better rinsing was a revelation. I've cleaned several lps from new to very rough record show finds. The improvement is easy to hear across the board.

About one year ago, I went through my Janis Joplin lps to compare different pressings. I have the MFSL 45rpm "Cheap Thrills". At that time I was very disappointed in it. So much so, I put it in my to sell pile. I re-cleaned it this morning and WOW!, it is a completely different sounding record. Actually, it is of reference quality. I'm not kidding.

Thank you for your posts!


@terry9 ,

Why finish with distilled if it’s not as pure as RO or the like?

I was just posting my initial findings, I think it may work???...not sure yet.
@slaw 

Good idea about the RO systems. Think that's absolutely right. I like to finish with distilled water.

Chemistry - I like to use 40:1, measured with lab glassware. But a measuring cup would work fine, if you are careful.

Glad to see that it's working for you. All the best.


@terry9 ,

I’ve been experimenting again... I can certainly understand now, why you describe your rinsing effort as heroic! Let me explain......

I’m still using my AD/distilled water. It’s at close to a complete water change. I received my Versa-Clean. I decided to just put in a small amount to my existing water. I did not measure it but I guess 2oz? When I pulled the lp out to rinse/vacuum on my VPI....major suds coming through the vacuum tube. So, I’m not even at the 20:1 ratio and still having a major amount of rinsing to do.

Mine is a 10 L tank but of coarse it isn't filled to capacity. It takes slightly under 2 gal to fill it to operating capacity.

@terry9,

I've ordered Versa-Clean and Photoflo. My plan is to use this with distilled water for the time being as my next phase of my progression of US cleaning.

I have two existing RO filtering systems. One I cut off years ago when a leak developed and an identical new unit never installed. I think I'll try to install/fix both and use one with a mineral cartridge for my drinking water and the other just for my US cleaning needs. Thoughts/suggestions?
Re-reading my post of March 6, I should have written

7. Observed no AUDIBLE change or difference of any kind.
Hello Audiom.

I use a 6 litre tank. Well made, good features, no regrets. Since it's a lab machine, I trust its specs - and the results are quite surprisingly good, even for my high expectations.
@terry9 Those Elmasonic machines look very nice!  What size tank are you using?
Hello Nolo. Welcome!

I have done such an experiment - it was my first act of US ownership. Methodology:
1.  Wash both sides with VPI 16.5.
2.  US clean both sides for 5 minutes.
3.  Turn off the motor, so that one sector of the record remained in the US bath.
4.  Cooked the record in US for an hour.
5.  Removed the record from the bath, and rinse.
6.  Play on a high end system, expecting a change every second or so.
7.  Observed no change or difference of any kind.
8.  Concluded that US does not damage vinyl.

Of course, after cooking in the hot bath for an hour, the record was warped - but that is a function of heat unevenly applied, not US energy.

My US cleaning process:
1.  Rotate at 12 RPH.
2.  Clean at 80 KHz with Elmasonic machine (German, lab grade).
3.  Chemistry is 2.5% VersaClean from Fisher Scientific.
4.  Temperature is 45C.
5.  Rinse heroically.

My system is based on 6 Quad 2905 ESL's, a DIY air bearing TT and DIY electronics.

For years I used a VPI 17 then Audio Desk followed by Klaudio were introduced and I began reading all the rave reviews. However, like nolojunko, I had concerns about exposing my records to ultrasonic cleaning. Let me add that my concerns were purely subjective without the benefit of any empirical evidence. As, a result I went with the Clear Audio Double Matrix Professional Sonic and couldn't be happier. It does a wonderful job and it's built like a tank.
Mulveling
Cool! Like minds and all. I didn’t think anyone read my posts. Thanks for letting me know I was wrong. Like you, I love my double matrix pro sonic. Makes life(vinyl) spin.
🖖✌️
@whatthe 
I too was considering the KL Audio & AD cleaners, and ended up with Clearaudio DM Pro Sonic. It's changed record cleaning (with a VPI 16.5) from a torture to a pleasure, which has become the most important parameter for me. And of course, it cleans EXTREMELY well, to great effect -- especially the heavy-duty cycle!