I see that there is only 14 hours left.... so if you are still considering....make up your mind FAST ;-)
Have they stated what frequency the ultrasonic operates at? I know this was discussed earlier in the thread but I don’t see anything specific to the HumminGuru. Edit: Oops I just found this on their site: Applying a duo 40 kHz ultrasonic system is powerful enough to remove the contaminants and dust on the vinyl record without causing damage. Because the application for the cleaning is vinyl chloride, there is not much difference between 40 kHz and 60 kHz ultrasonic system in terms of cleaning effectiveness.
About 4 hours left....and only $3800 from unlocking the 10" insert. Fingers crossed. only about 10 more backers needed to reach that extra perk ;-) HumminGuru | All-in-One Ultrasonic Vinyl Record Cleaner
With 3 hours left, looks like they hit the 10" stretch goal at at $456K.(Amount for the 10" was $452). HumminGuru | All-in-One Ultrasonic Vinyl Record Cleaner
Looks promising but I will wait until its released (if ever) and for the reviews. Even if the retail price goes up a bit ot will have been worth the piece of mind. I have a vc-s and while it's fine, it's a time consuming manual intensive pain in the ass. Putting in a record and walking away is very appealing but not for a $3k degritter
Sorry if this has already been answered, but is there a definitive take on whether 40 khz is as good/better/worse than a 120khz US record cleaner, and why?
Nothing definitive. It just means smaller, more gentle bubbles. Those who worry about there somehow being damage feel better about it, but it should also mean less effective cleaning I suppose, nothing tested though.
I wrote to an engineer sort of guy in 2014 with the frequency question: Good morning and thank you for your interest in xyz ultrasonic cleaning systems for cleaning vinyl LP records. 60kHz would be an acceptable frequency for this application, but if xyz were manufacturing it, we would provide 80kHz due to its more evenly-distributed energy distribution, and less damage potential. Unfortunately, we do not sell a system dedicated to LP cleaning as those I have seen. The rotation in these systems is a very good idea, since it keeps the object in motion and aids in damage prevention. At 80kHz, the LP could be cleaned stationary, with intermittent rotation by hand, and I have heard of others doing this to reduce the cost. I always try to remember my turntable and listening setup is not inside a sterile cleanroom, so while pursuing really darn clean vinyl is noble, the fact is your efforts are likely going to be more undone by 'dust' that will fall setting the clean LP on the table, than the matter of ultrasonic frequency used to have just cleaned it. Of course, YMMV.
There are a number of definitive test results from industry and here is a quick summary: 1. Power to cause Cavitation is proportional to kHz: 40kHz requires less power than 120 kHz. 2. Cavitation Intensity is proportional to kHz & power (& tank size): 40kHz can have twice the cavitation intensity of 120 kHz. For power this is the point when any more power does not increase cavitation intensity. 3. Particle Removal: >2-5 microns 40khz is more efficient. <2-5 microns 120 kHz is more efficient. 4. Cleanliness Level: The higher kHz units can achieve a cleaner surface but that that does not mean they clean all surfaces. If the surface is really dirty - you need the lower kHz. 5. Tank flow rate: If the tank flow >50% of the tank volume cavitation intensity drops. The HumminGuru has pro's & con's. The very small tank volume is not going to need much power to get good cavitation intensity. But too much power and with the low kHz, there could be the risk of damage; and the that small tank volume can heat fast. Given the cost & size, - the risk of too much power is probably very low. However, with the record spinning, even slowly, its agitating the fluid and given the likely low power, there is risk of reduced cavitation intensity caused by the record agitating the fluid as it rotates. With only a tank volume of 350 mL, if agitation (equivalent flow rate) = 175 mL/min develops, cavitation intensity will drop. The Degritter in comparison has a tank volume of 1400 mL, so the risk of record rotation causing enough agitation (700 mL/min) to cause too much equivalent flow is much less.
I have been playing with some numbers to try to bound that question and came-up with the following thumb-rule; 1 rpm = 1 lpm equivalent flow for each record and do not exceed a flow rate >50% of the tank volume/min. The derivation is as follows: 1. Assume 0.333% of the record is in contact with the fluid and by a calculation the record (minus label) per side is 1-ft², so at any time 0.67-ft² are in contact with the fluid. 2. Assume that as the record rotates, it will agitate a film of fluid 0.25-inch thick on each side. Therefore, as the record rotates, the volume of water that is agitated = (0.67-ft²)(144-in²/ft²)(0.5-in) = 48.25-in³ = 0.8 mL. 3. However, the faster the rotation, the more fluid is moved because of drag, so a 25% factor is applied for uncertainty to yield a simple thumb-rule that the rotating record is agitating/moving 1 liter of fluid; and a rotating speed of 1-rpm = 1-lpm. So, for a single record in a 6-L tank, the maximum speed for 50% tank flow is (6-L)(0.5)/(1 record)(1 lpm/rpm) = 3.0 rpm. The more records you clean at once, the slower the speed you need and/or a larger tank. Remember, this a ball-park estimate - there's no computational fluid dynamic analysis, but if you take the above thumb-rule and you apply it to the well designed system such as the Kuzma™ RD Kit which is is often used with the Elmasonic™ P 120-H ultrasonic tank that has a volume of 12.75 liters and can clean 10 records at a time: Apply the thumb-rule 1 rpm = 1 lpm, the maximum speed for 50% tank flow is (12.75L)(0.5)/(10 records)(1 lpm/rpm) = 0.64 rpm which is right at the maximum speed (0.6 rpm) of the Kuzma™ RD Kit. So, the derivation and use of the thumb-rule 1 rpm = 1 lpm appears reasonable and its independent of kHz. The above info will be included in the 2nd edition of my paper.
Read the article Precision Aqueous Cleaning of Vinyl Records-2nd Edition - The Vinyl Press and then click on the big red download button (at 145 pages, its more of a book; lots of info). The info I addressed above is in Chapter XIV which is exclusive to ultrasonic units. If you read with Adobe, there is a document tree and the 'book' is cross-linked throughout for all references and for Chapters, paragraphs, tables and figures.
Jesus. Dunno if it’s a mistake or what, but pre-order just went live at 2.9K for the base package, and 3.3K with the 7” and 10” adaptors. Are they kidding?
