I'm a Dummy, Tell Me About Turntable Mats

I pay no attention to it, because my listening seat is far enough away from the turntable that I never hear it while I am trying to concentrate on what is coming out of the speakers. What’s the big deal?

Anyway, I view it as a "problem" endemic to vinyl reproduction, and it probably varies all over the place based on the tonearm design and construction and the cartridge design and construction,

@lewm

Its a problem due to poor platter pad design, because most people don’t have an idea how important the role of the platter pad actually is. People do seem to have noticed that they change the sound; since that is true it follows that there is something going on that’s worth actually applying some engineering time to sort it all out.

I’ve explained what’s going on with this any time this subject has come up. The resonance of the LP as the stylus tracks it **has** to be controlled, else the system simply won’t be neutral! The stylus has to get things right- you can’t fix it downstream. If the LP resonates as the stylus tracks it, that energy talks back to the stylus, reducing clarity and increasing harshness. IOW the platter pad is pretty important to getting things right, much more so than most people seem to realize.

That is why the Origin Live Mat works so well. This is an engineered material with different characteristics at the record/mat than mat/platter. The goals are to avoid reflecting vibration back up into the LP, to absorb/dissipate them in the material, and to do all this uniformly across the full range of frequency and dynamics. Simply felt or rubber mats just aren't up to the task. The best they can do is make a few areas better at the cost of making some other areas worse. In other words like Ralph says they will not be neutral.

@astolfor PM me. I have an unused SPH Cu mat.

Thank you atmasphere, I think you said it better than I. 
Lew, I know of no hard data that says it is a definitive sonic problem. We both know it exists because we hear it directly. If we hear it the assumption would be the stylus does also. I apologize if I contradicted myself. But it is useful to define our terms so we all know what we are talking about. Record noise is what you hear in the background behind the music including dirt and scratches. Let us say that tracking noise is the noise generated directly by the stylus tracking the record which in all respects is just like that diaphragm in the Victrola. The mat has to dampen the resonance without reflecting it back. IMHO the record has to be held down tightly as the mat is not doing it's job if the record is partially in the air. I think the fact that disabling the vacuum increases tracking noise is telling. You use the Sota reflex clamp which performs the same function as long as you are using that washer over the spindle. Keep your amp off and listen to the tracking noise with and without the clamp. See if you get the same results I did.