Ultrasonic Cavitation & Cleaning Explained

[rich121]

And here is two other quotes from the book:

XIV.1.7 Standing Waves: In a traditional UCM with bottom firing transducers, the acoustic waves that are propagating upward through the liquid will reflect downward from the fluid surface. When reflected downward the acoustic waves will combine with the upward acoustic wave and the subsequent wave can be constructive(amplifying) if in-phase or destructive (attenuated) if out of phase. Ultimately areas/layers of higher acoustic energy/cavitation (standing waves) will form and there will be areas/layers of lower acoustic energy/cavitation. The standing waves tend to layer at a distance 1/2 of the wavelength with Table XXI showing the wavelengths and resultant standing wave of common UCMs frequencies; highlighted blue. The spacing of the standing wave is relative to themselves. Their position in the tank relative to a fixed point is dependent on the reflected surface – is it hard or soft; water height and other factors such as the type of transducer and water temperature. Based on an article by the late John Fuchs Ultrasonics - Near Field and BEYOND! - CTG Technical Blog (ctgclean.com), the first standing wave reflected from a hard surface (such as a tank metal wall) is about 1/2 the wavelength, while the first standing wave reflected from a soft surface (such as the water surface) is about 1/4 the wavelength. So, for UCMs with bottom firing transducers and the Degritter™ with side firing transducers into the record (soft surface), the location of the first standing wave relative to the water surface or record could be as close as 1/4 wavelength. Subsequent standing waves will be spaced about 1/2 wavelength apart.

And this is mostly associated with bottom firing transducers:

XIV.1.8 Sweep Frequency: Many ultrasonic tanks advertise a “sweep frequency” function. The “sweep frequency” function essentially modulates the main ultrasonic frequency about +/- 1 to 2 kHz with results shown Table XXI. The intent of “sweep frequency” is to minimize narrow standing waves that will form in the tank when using a fixed frequency which is valuable for cleaning parts that are layered static in a UCM. Sweep frequency tends to equalize the cavitation intensity throughout the tank. But the record(s) is rotating and standing waves may be beneficial since the record is exposed to a scrubbing type action as the record alternately moves from areas of lower cavitation intensity to areas of higher cavitation intensity.

Thank you Neil.

 

[tima]

"I've never experience any record damage from cleaning at the low frequency."

Tell us how you've determined this. I'm sure it'd be a function of power intensity, duration of exposure, cleaning agent used, and other variables. And how do you examine your records to determine whether or not they've sustained damage during the cleaning process? A profileometer, SEM, naked eye? What does that process entail?

I play the record.

 

[bazelio]

I play the record.

Ok so you probably shouldn't claim that you've never damaged a record.

 

[tima]

Thanks for your opinion. I stand by what I said.

 

[abeidrov]

I was somewhat interested in the Kirmuss (sp?) machine after inspecting it at THE Show this weekend. However, the guy in the white lab coat (Milligram's experiment anyone?) spent too much time trashing his competition for my liking. He also said that Tergitol should never ever be used on vinyl records and when I referenced the literature to the contrary that we've discussed in this forum, he simply said he was familiar with it and it's wrong. I need to look at the Tergitol MSDS and research a bit. But for now, I'm confused.

I agree that Mr. Kirmuss has a certain personality and some of his statements are a bit on an aggressive side, but his cleaning process, although tedious and very time consuming, produces excellent results. At least in my case, I’ve had a few old records cleaned with Klaudio, and they still had some pops and clicks. Not so much after going through 4 to 6 cycles in the Kirmuss machine.

 

[bazelio]

I agree that Mr. Kirmuss has a certain personality and some of his statements are a bit on an aggressive side, but his cleaning process, although tedious and very time consuming, produces excellent results. At least in my case, I’ve had a few old records cleaned with Klaudio, and they still had some pops and clicks. Not so much after going through 4 to 6 cycles in the Kirmuss machine.

Do your records come out of the Kirmuss dry without the need for further drying as Mr. Kirmuss claimed they would?

 

[abeidrov]

Do your records come out of the Kirmuss dry without the need for further drying as Mr. Kirmuss claimed they would?

Yes, they do, almost completely dry, just a few drops of water on each side. It takes about a minute to dry them with the cloth and polish with the supplied brush as per this video:

 

[bazelio]

Yes, they do, almost completely dry, just a few drops of water on each side. It takes about a minute to dry them with the cloth and polish with the supplied brush as per this video:

Ok, good. Despite my dislike for the Kirmuss trade show tactics, I'm still somewhat interested in the product. The immediately obvious downside in my mind is the limitation of three full sized records combined with the long cycle time. But perhaps used as a post-Degritter ultrasonic rinse step with shorter cycle time, it could have utility for me. And I guess, averaged out, the time per record isn't too far off from what my Degritter workflow yields.

 

[mtemur]

I don't want to risk inner groove damage from a cleaner though. Perhaps I already am since this is a discussion of a topic that has no data to substantiate any claims. Horses for courses.

Is there any data for damage caused by stylus? Or brushing or sleeves? Lack of data on those doesn't keep anybody using them.

We need to consider the type of damage and degrees of damage. It's not black and white. Listening causes wear and I'm personally ok with that simply because i like listening.

Why you're ok with damage caused by stylus but not ok with damage caused by ultrasonic cleaning even though there wasn't any obvious sonic degradation but oppositely there is sonic improvement? Couldn't it be possible to be personally ok with damage caused by ultrasonic cleaning simply because it sounds noticeably better?

 

[bazelio]

For stylus damage yes. You can find it if you're so inclined. A poorly aligned micro ridge is worse than a poorly aligned conical for example.

I don't trust other people's ears when they claim something like this isn't audible. We all listen for different things.

 

[Neil.Antin]

Listening is obviously not a valid approach for determining whether or not damage has occurred. Temperature is but one variable and I'm more concerned about damage that might occur even under lower temperature conditions inside units such as the Elmasonic due to the characteristics of the unit itself rather than other factors. Temperature, TDS, etc can be monitored but doing so may still be insufficient for avoiding damage. And it's a question / concern that hasn't been satisfactorily answered. Thank you for your insight.

Temperature alone did not cause the damage; kHz alone did not damage the record, power alone did not cause the damage, and record rotation alone did not cause the damage. BUT, high temp, low kHz, high power and very slow rotation now changes the equation, and the record may be damaged. As @tima said, a good process is not going to damage the record and given his UT process and his stereo system and his sensitive hearing, you should trust his experience, regardless of what I say or have written in the book. However, I am not here to convince you that UT is safe; I am not selling anything.

 

[bazelio]

@Neil.Antin , Listening tests are flawed in multiple ways and I'm interested in data, though there isn't much to be found. Are you familiar with the Kirmuss metal (aluminum?) disc demonstration? He shows these discs that have supposedly been run through different machines as evidence of their cavitation efficacy. The Kirmuss aluminum disc was essentially deformed by the ultrasonic action where as the Degritter disc remained smooth. There were other discs from other types of machines (I think Kuzma was one). And the lack of deformation of an aluminum disc was one reason he sited for claiming the Degritter is merely a bubbler. But I looked at the disc test as possible evidence that the other cleaners or methods or both could actually damaging the media. At least it seems difficult to confidently rule it out.

 

[Neil.Antin]

@Neil.Antin , Listening tests are flawed in multiple ways and I'm interested in data, though there isn't much to be found. Are you familiar with the Kirmuss metal (aluminum?) disc demonstration? He shows these discs that have supposedly been run through different machines as evidence of their cavitation efficacy. The Kirmuss aluminum disc was essentially deformed by the ultrasonic action where as the Degritter disc remained smooth. There were other discs from other types of machines (I think Kuzma was one). And the lack of deformation of an aluminum disc was one reason he sited for claiming the Degritter is merely a bubbler. But I looked at the disc test as possible evidence that the other cleaners or methods or both could actually damaging the media. At least it seems difficult to confidently rule it out.

Listening tests can be flawed, but not necessarily with how UT could damage the record. From all the videos Iinks that I have provided, you should be sensitive to how UT could damage the record - if it damages the record, it should be some form of abrasion - such as the dull-mottled surface finish or like the cavitation damage to metals - the surface is pitted. If the surface/groove is pitted, you should hear that.

Otherwise, yes, I am familiar with the aluminum foil test - read this post Degritter Users | Page 102 | Steve Hoffman Music Forums.

 

[bazelio]

Listening tests can be flawed, but not necessarily with how UT could damage the record. From all the videos Iinks that I have provided, you should be sensitive to how UT could damage the record - if it damages the record, it should be some form of abrasion - such as the dull-mottled surface finish or like the cavitation damage to metals - the surface is pitted. If the surface/groove is pitted, you should hear that.

Otherwise, yes, I am familiar with the aluminum foil test - read this post Degritter Users | Page 102 | Steve Hoffman Music Forums.

Yeah, I think we're at an impasse w.r.t. damage. The available information and "shoulds" are inconclusive. I'll leave it at that. By the way, have you addressed or considered whether or not being in close proximity to a high powered ultrasonic machine (e.g. 100W to 300W at XX kHz) could have detrimental effects on our hearing? I always wear ear plugs when operating mine because I simply don't know!

 

[Neil.Antin]

Yeah, I think we're at an impasse w.r.t. damage. The available information and "shoulds" are inconclusive. I'll leave it at that. By the way, have you addressed or considered whether or not being in close proximity to a high powered ultrasonic machine (e.g. 100W to 300W at XX kHz) could have detrimental effects on our hearing? I always wear ear plugs when operating mine because I simply don't know!

It's inconclusive because of the many variables. But consider that the precision cleaning industry has been using UT to clean delicate parts for >50-yrs and uses mega-sonics to clean semi-conductor chips. It's all about the kHz, power, temp & exposure duration. But if you are the least concerned - do not buy the Kirmuss with its 37-kHz large cavitation bubble/high cavitation energy. As I wrote the 120kHz Degitter produces a much smaller bubble but do not compare its power (300W) with the power of a lower kHz unit since as I wrote, the higher the kHz the more power that is required to produce cavitation - the book Chapter XIV goes into some detail.

Otherwise as far as hearing damage - there are no OSHA regulations, but there is some literature about it (PDF) Effects of Ultrasonic Noise on the Human Body—A Bibliographic Review (researchgate.net) and Possible Effects on Health of Ultrasound Exposure, Risk Factors in the Work Environment and Occupational Safety Review (nih.gov)

 

[Neil.Antin]

Listening tests can be flawed, but not necessarily with how UT could damage the record. From all the videos Iinks that I have provided, you should be sensitive to how UT could damage the record - if it damages the record, it should be some form of abrasion - such as the dull-mottled surface finish or like the cavitation damage to metals - the surface is pitted. If the surface/groove is pitted, you should hear that.

Let me add this:

What is the 'weakest" part of the record? Answer - the side wall ridges that produce the high frequencies. The peak of the modulation is very thin. Its the first place that stylus groove damage occurs - the stylus trenches the groove. Ergo, common sense - be it damage by a cleaning agent or a cleaning process - the first place this will occur is the side wall ridges and the likely result (given the variables) is either high frequency noise or loss of high frequency dB output. People have digitally recorded records before and after UT (37kHz and above with a protective process) showing no damage to the high frequency content. I do not have the links readily available - but if you dig around you should find them. Now there was an early post by Harry on the now gone VPI Forum addressing audible loss of high frequency content after UT - that was later determined to be failure to fully rinse cleaning agents that were being used.

 

[tima]

If there is fear of damaging a record from ultrasonic cleaning or the mere lack of data about it, just think of all the other ways vinyl records can be damaged -- as noted by @mtemur . One with such fear may feel more comfortable if they confine themselves to digital.

 

[XV-1]

@tima, @bazelio, @marty:

Make no mistake, that the powerful UT tanks that are used being used for record cleaning can damage a record. I recently assisted someone who was using an Elmasonic P60 with temperatures as high as 50C with a Vinylstack spinner at about 0.15-rpm, and at least one record was damaged. The record surface took on a dull, mottled finish. Now there was no subjective audible damage but without comparison to a new record that could be debatable.

Now in this case, four factors were in play - the high power of the Elmasonic, the 37kHz which with power can damage surfaces (with the power of the Elmasonic and 37kHz - it could pit gold), the high temperature and the very slow spin speed.

When people try to compare other uses of UT to UT for record cleaning, very often the comparison is not applicable. Always remember, there is the power needed for onset of cavitation, which is not that much, and then there is cavitation intensity which is power dependent. Cleaning jewelry is easy and does not need a lot of UT power and given the nature of the substrate that is metallic or jewels that are relatively soft, you definitely do not want a lot of power - it will pit the surface. Additionally, the surfaces do not want to hold on to detritus like a record does.

The record is a rather odd beast to clean. The stylus can produce an audible response equal to a displacement of less than 1-micron, and trying to remove particles and films this and smaller is not easy. And this is complicated by the material (the substrate) that has these wild properties - first its plastic which wants to hold on to all forms of detritus - this isn't Teflon, its elastic - it's not rigid like metal so it can deform under high cavitation intensity, and it has this crazy looking groove with side wall ridges - it's like trying to clean the Grand Canyon.

So, on first glance the record appears pretty simple, but dive deeper and it becomes quite a challenge to clean it well enough to recover all the music it can reproduce with mostly absent any crackly background.

Ultimately the devil is in the details.

Take care,
Neil

Are you stating that KL ultrasonic cleaners damage records?

If you are not, why are you polluting a KLA ultrasonic thread with this stuff?

 

[Neil.Antin]

Are you stating that KL ultrasonic cleaners damage records?

If you are not, why are you polluting a KLA ultrasonic thread with this stuff?

You have taken what I said out of context. I am not saying that KL ultrasonic cleaner damaged records. I reference where someone used a DIY w/Elmasonic UT incorrectly and the record was damaged. The KL audio is an automated machine that has been well designed to operate w/o damaging a record.

Otherwise, this is nothing more than an intellectual discussion in response to someone challenging whether UT damages a record - read back on this thread; and maybe in hindsight, the conversation should have probably been moved to another thread.

 

[tima]

Are you stating that KL ultrasonic cleaners damage records?

If you are not, why are you polluting a KLA ultrasonic thread with this stuff?

While I cannot speak for Neil, I don't believe their is any speaking ill of KLaudio. Neil is stating facts about ultrasonic tanks in general. The message (to me anyway) is that ultrasonic tanks are a tool and when used correctly can do a fine job cleaning records, KLaudio included.

Edit: what Neil said above, I was writing when he posted.