Some thoughts on dust covers

RB, to the question contained in your last paragraph, my current opinion, open to change if presented with contrary data (not a “belief”), is based on my data, the testimony of another Forum member who’s done the experiment many times before me with his own meter, and on the Shure Corporation white paper. You can buy a decent ES meter on eBay for less than $200. Why don’t you buy a meter, make some measurements, and then we can discuss. Don’t come to me with “Google AI” and no actual data or a reference to someone else’s actual data that is publicly available. The concept that the diamond on vinyl causes static charge is repeated over and over again in advertising for anti static devices, in audio forums like this one, etc. So it does not surprise me that Google AI believes it. I insulted you earlier,so I’ll forgive you for insulting me. If you want to go into detail about ES force vs gravity force, probably that would bore everyone else. But it’s not relevant.

Wyoboy, sorry I over-reacted.

Yes I read the Shure papers.  You are right there is no data to back up their assertion. I don't know what happened to my Dust Bug either.  Maybe it generated so much static charge that it self repelled into the dust bin?  (Just kidding) Pity because it definitely appealed to me as a good idea back around 1969 or there abouts.  Certainly an option for the dust cover-less.  As I recall at that time I was struggling with an AR turntable.  Horrible thing.  Hated the arm.  The dust cover for it got deep sixed very quickly.  And Bob's your uncle, I bought a Dust Bug!  Which worked a treat and stayed with me through a succession of turntables.  I wouldn't be surprised if it is still in service on my old TD-125 somewhere.  But let's think this through together.  The footprint of a Dust Bug is considerably greater than the contact area of even the worst case conical stylus.  If the Dust Bug did not generate significant static charge, and I posit that to be so, then it is reasonable to deduce that a stylus tracking the record grooves should certainly be even less.  And without the means to measure the actual number, as reasonable people we can accept Shure's assessment that the amount of static generated by a stylus on a vinyl record, while somewhat above zero, it is negligible for all practical purposes.

I can't resist. Too much idle time. The equations of Newton and Coulomb are quite adequate for considering the situation at hand.  You used their constants yourself as a basis for your statement about the relative magnitude of the two forces. No need for a unified theory here, which anyway does not exist. The reasons that your blanket statement about the relative strengths of gravity and electrostatic charge does not hold water are at least two-fold: (1) The units of the gravitational constant and Coulomb's constant are different. You cannot just assume that a numerical ratio between two different quantities is meaningful without considering the units (apples and oranges), and (2) in one case the objects are considered only for their mass (Newton) and in the other case the objects are considered only for their charge (Coulomb). I would say yes, in some cases the ES force can be greater than the gravitational force.  In other cases, no, gravity dominates.  It depends upon mass vs charge. One other difference between gravity and the ES force is that gravity is generally a force of attraction between two objects, whereas the ES force can be a force of repulsion, when the charges are alike in polarity, or attraction, when the charges are opposite in polarity. (Yes, I know about the question of whether the reason the universe is expanding means there is a repulsive form of gravity caused by dark matter, etc. But that is not an earthly problem.)

My-O-My !  I never expected to kick up so much "dust" with my re-telling of the story of when my audio dealer dusted his turntable dust cover and created enough magnetism to alter the stylus force !

Perhaps we can end it all simply by turning our attention to another interesting thing I noticed on my 1920's Victor "Credenza".  On the lowest portion of the rather sizeable and heavy lid is a decal that states, "Close Lid Whilst Playing".  Since it was effectively the turntable dust cover, I hope to stay within the confines of the original post.   There definitely is a difference in the quality of sound when following the directions though I've never decided whether it was a diminution of the very noticeable stylus "scratch" or a real enhancement of the sound as a result of confining the sound box to a more restrictive acoustic.  Victor even encouraged the regimen of closing the lid by providing the lid with two "dashpots" which damp the lid closure enough to prevent any slamming effect.  On the Columbia "360" record player from the 1950's, the edges of the lid were lined with felt so that when the lid was closed it definitely created a different acoustic situation in which the cartridge had to function. The Speakers were located on the opposite sides of the unit and one driver was purposely wired "out of phase" to create a diffusive effect.   Later models of the "360", though much more modern in the cabinet design, went even more deeply into the idea of encapsulating the cartridge in its own acoustic by integrating a fully sealed plastic container within the player to isolate the cartridge even more fully than the original model.  You almost have to pry the lid to open it !

My question is :  Were there any modern turntables that had a dust cover/lid that was designed purposely to be closed during the play cycle to take advantage [?] of the difference between an open or closed acoustic surrounding the cartridge ? Some of us have certainly experienced acoustic feedback when positioning a loudspeaker too close to a sensitive turntable that created an acoustic feedback through the cartridge, so the reasoning follows that attention to the acoustic in which a cartridge must function is important.

I own both an early and late Columbia "360" machine and there are mono records that sound like fine stereo recordings on these machines !  Amazing !!   The outer lids on both the Victrola and the Columbia "360' machines were of wood so they could not be magnetized.  Thoughts ?   Experiences ?

I think the easy way out of this impasse and high blood pressure is….

Cover or lid, which ever way you want to play it…..

———————-

1. If the thoughts of dust filling your groove ruins your musical enjoyment, and have a lid…keep the lid down.

2. If you are worried that the sound will be compromised with the lid down or know it will be, as Arnie would say….’Don’t dooo iit!

3. If your hi-fi sounds great to your ears, you are happy with listening to music and you don’t notice a difference up or down….and have a lid, stick it down and save a lot of additional cleaning!

4. If you have a turntable without a lid, content or enjoy sometimes a little dusting fore play each time you want to listen….stick to a turntable without a lid!

I think l have about covered it?

That’s my Logic