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Platter mat insanity

I was doing an idler upgrade to my 401 (more anon) and when finished used the Keystrobe disk to ensure speed. I use a 10" EP as a platter mat. I played a bunch of albums and it sounded fantastic. On the 6th side, I noticed I'd forgot to remove the 4" strobe disc. Duh. I took it off and figured VTA was responsible. So I lowered the arm to see if that made it sound so good. Nope. Put back on the 4" strobe disk and raised arm. The awesome sound returned. So air under the record removed haze, smearing, flattened soundstage and muddled bass; and made it so more musical. Comments... 
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bdp24
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I like and agree with all of Victor Pattachiolla’s designs EXCEPT the Resomat. The Salvation turntable, excellent; the Terminator arm, excellent (and a great value). But the Resomat, like the Transcriptors turntable, suspends the LP in air, not a good idea imo.

It was long ago established that an LP groove being traced by a phono cartridge stylus causes the vinyl to vibrate/resonate like crazy, especially if the vinyl is suspended in the air, with no surface below it to absorb and damp that vibration. The vibration in the vinyl created by the stylus travels from the location of the stylus in the groove both out to the edge of the LP and in to the center hole of the LP, that vibration then reflected back from those locations to the stylus, where it is read by the stylus as a time-delayed "echo". How can that be a good thing?! Yes, the echo is a very low-level signal, but the dimensions of the LP groove, and the amount of travel exhibited by the stylus, are extremely tiny, and very vulnerable to any added vibration. IMO, a solid surface in full contact with the LP, the material of that surface intended to absorb and damp the vibrations inherent in LP playback, is the "correct" approach.

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noromance OP
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I would agree with you if I didn't hear what I hear. It isn't a brightness or an edge to the music masquerading as additional information from the grooves which you might get with what you describe. It is an opening up of the soundstage and a removal of noise and confusion. Bass is much cleaner, yet goes deeper when called for. Audience sounds are improved and dynamics more real and almost startling. The instruments take on more color with piano hammers and cymbals presenting texture where with a mat there is none. I'll give it another test tonight.
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noromance OP
9,869 posts
 
Looked at this critically last night. 
Notes:
1. The LP is not stable at all while perched on the strobe disk. Not that I don't know but as @slaw pointed out, the label recess is absent.
2. I ruled out any VTA issues for certain.
3. I removed all mats (10" EP and strobe disk) and tried 3 tiny 5mm high stone tiles between record and platter. Same result with previously noted improvements. (Music became slightly "harder" as the material suggests)
4. Rooting through the workshop, tried 3  tiny flathead brass bolts with screw heads on platter under the label, thread end up. This was quite stable and gave very good results. I am going to explore this path in more detail.
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cleeds
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bdp24

... It was long ago established that an LP groove being traced by a phono cartridge stylus causes the vinyl to vibrate/resonate like crazy, especially if the vinyl is suspended in the air, with no surface below it to absorb and damp that vibration ...
Please tell us who you believe established this effect that you report as fact rather than theory.
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bdp24
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David Fletcher, Marcel Riendeau, Peter Moncrieff, George Merrill, Austin Jackson. There are others, but that’s enough to get the sincerely interested started.
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