Objective Data re: Record Cleaning


There are many threads about record cleaning, and different techniques for cleaning.  Most writing about audio is inherently subjective but this strikes me as one area that might be analyzed with real data.  Ironically it might require some digital tools to do so.

  For example it should be possible to measure the amount of pops and clicks digitally in an lp pre and post clean.  Perhaps take 3 digital readings pre and post clean and do this for 100 LPs were cleaner to measure the delta.  Many other variables would have to be controlled, such as stylus wear and dust accumulation, but this should be doable.

  Forgive me if this has been previously discussed, and if so please direct me to the relevant thread.  A quick search on my end didn’t reveal much 

  

mahler123

To objectively measure the efficiency of a cleaning process, you always start with a known contaminated standard and then measure how much of the contaminates were removed.  This is generally accomplished with parts of a specific area and weight with a known weight of standardized soil applied, and pre and post weights are compared being one criterion, another being a wash with a powerful solvent to measure non-volatile residue (NVR) and another being a particle count.  High magnification could also be used, but the inherent problem is field of view - you end up looking at a very, very small area.  For large surface areas, and complex geometries (i.e., a grooved record) often statistical measure are applied based on allowable contamination (NVR & particles) per sq-ft or sq-in or for semi-conductor chips much smaller with crazy NVR and particle count requirements.

But the record presents a unique situation since every inch represents valuable data.  So, a small area sample would likely not be representative requiring a larger area which then adds a lot of complication to the test.  Record contamination with hard non-viscous detritus (such as a particle) can cause the ticks and pops, but soft viscous detritus (such as a cleaner residue) can cause loss of high frequency information.  

If you read this article on UT, pay attention to the particle cleaning efficiency between 40-kHz and high kHz - awad-reprint II (crest-ultrasonics.com)Recent investigations have confirmed that higher frequencies are more effective for the removal of certain contaminants.  Reports on particle removal efficiency have shown that the removal efficiency of one micron and submicron particles in deionized water has increased with the higher frequency. At 65 kHz, the
removal efficiency of a one micron particle is 95 percent, versus 88 percent at 40
kHz. A similar increase in efficiency results was reported for 0.7 and 0.5 micron particles. 

If you did a rigorous record cleaning test, you would more than likely find that there were efficiency differences in any single step with different equipment and different chemistry but combined in a process of pre-clean & final clean they could all yield very high cleaning efficiency with only small differences at the higher end with higher end not necessarily defined by the most expensive process.  A lot of expense is for convenience.

Just some thoughts.

PS/Precision cleaning processes, cleaning efficiency and cleanliness verification is something I did for the Navy for 20-yrs for high pressure oxygen (and other compressed gases) and life support systems.  

I don’t think that weighing records pre and post will tell us much.

Since these particles are so small I am not sure how useful studies showing more or less sub 100 micron particles have been removed are.  It might mean something but it would be awfully difficult to control for small particle contaminants pre and post clean.   
  What truly matters to me would be how the record sounds.  That is why I am wondering if there is any objective measure-such as pops and clicks- to go by.
  

When measuring weight, the samples are measured to <0.01 mg and particle counts below 50-micron are normal noting that the nominal width of the groove (at the top) is 50-microns.  

Otherwise, Parks Audio phono-preamps Parks Audio (parksaudiollc.com), the current WAXWING and the older PUFFIN both have a Grade feature parksaudiollc.com/waxwingmanual.html and C:\Users\parks\AppData\Local\Temp\mso6045.tmp (parksaudiollc.com) - This function determines a letter grade for an album side based on scratches, vinyl surface noise, and groove wear. It works best in conjunction with your own ears.  You can do before and after.  However, how the Grade feature functions is unknown, and once you introduce "how it sounds" that's subjective, leaving you with the many current reviews and opinions.