Speakers Corner

Do I believe in dust and dirt? What is this? The Interfaith Council on Faith in Reality? I simply reported that Speakers Corner stated that Pallas doesn't use mold release compound, so the necessity of cleaning is obviated for those who would otherwise clean the records after purchasing. The reason that I asked the question to begin with was the because the record sounded so pristine already that I didn't want to do anything further to muck up what I was already experiencing. The company confirmed that. I don't believe Pallas would have any incentive to mislead on this question because it would affect future sales if the records did indeed become affected later. 

I have otherwise been cleaning all of my records. I think the mold release agent is often audible as a kind of haze hanging over the recording. I notice a strong difference after doing so, but I also notice on occasion that the cleaning introduces other sonic artifacts, so I'm not always comfortable with doing so.

Washline- if you go back and read my post, you'll see that I mentioned the fact that the so-called mold release is already in the pellets of PVC compound that are used to make the records. So, the notion that Pallas says they "don't use" mold release compound does not really address whether there are mold release agents, or other ingredients  in the vinyl compound itself that make it easier for a record to be removed from a stamper. There are a number of threads on this. I contributed to a couple, so I'd have to find them and give you links. 
I think the whole "mold release" thing is exaggerated, but it is very hard to get to the bottom of this- I did a fair amount of research on older vinyl compounds and found several papers published by the AES and some information in patents that described what goes into PVC for records. The formulations are often proprietary, so it's hard to pin down exactly what is in a given product, and presumably, a label or plant could order something that is different, from a different supplier, or with a different make up, than another record plant. (I don't know if you remember the whole thing about "Clarity" vinyl toward the end of Classic Records' production, but Mike Hobson claimed that eliminating the carbon black--used for antistatic purposes--improved the sound because it had electro-magnetic properties that interfered with the performance of the cartridge). 

As to cleaning, it seems to be a subject that everyone has a different view of- if your Speakers Corner copies play cleanly out of the sleeve, enjoy them. You might also investigate some of the original pressings that they remastered for their catalog. Although some are expensive, others aren't and if you are interested in what the differences in different masterings, tape sources and the like contribute to the end result, sonically, it is actually a fun process to compare pressings. 

Thanks whart. That's a highly informative post. I don't believe I read anything about Clarity vinyl, but that's also quite interesting and I'm surprised that manufacturers haven't followed up on it. I have to wonder though if a mold release agent is already present in the PVC pellets prior to being pressed would this necessarily affect the release of the record from the mold if it lies buried inside the record during the pressing process? Is it possible to clean this agent from the record if it is present during the entire process? Do thermal stabilizers also affect the sonics of the final product? Are those also removed during normal record cleaning?

In any case, I am going to investigate more of what the label offers in my areas of interest.

Wash- it’s all part and parcel of the compound. With modern plants, as I understand it, the pellets are melted and extruded into nuggets/biscuits and that is what gets put onto the press. It’s not like the mold release is a liquid blob inside the nugget, it is all mixed together with various other materials that all perform different functions. I’m not a chemist or materials scientist, so the best I can do is tell you what I can glean from the old papers or patents- issues like "flow," stability, surface noise, evenness of heat application, discoloration- I can point you to some of the papers- some are only available through the AES by paid download or subscription to their library. One scientist was at RCA, and had written extensively on what was necessary to make a "modern" LP circa the ’70s. That wonderful JVC formulation used in the old MoFi’s was originally developed for Quad LPs.
There are clearly some sonic differences I would attribute to the vinyl used, but couldn’t tell you what role the constituent elements played. And no, as far as I know, none of this stuff would (or should) get removed by cleaning. The biggest issue I can think of-- which isn’t all that common, but occurs- is a chemical interaction between certain plastics and the record- for example, PVC outer record sleeves, which have plasticizers in them to make them soft. Those plasticizers will leach (through the cardboard jacket, the inner sleeve and onto the record itself) and in some cases, create a haze on the record that you can see and will affect sonics. I suspect it is also exacerbated by heat, i.e. storing the records in an attic. Cleaning won’t get rid of that- but that’s a chemical reaction- it’s like the off-gassing of the stuff in car dashboards that makes your windshield hazy.

Speakers Corner is one of the last great Lp reissue companies.

There are threads on mold release compound, what it is, if it exists at all, etc.

Do a search!

IMO it is nothing to worry about. 

If you clean before first play, its up to you.  I do not, except if the Lp is used.