[rcag_ils]

Don't go matless with a steel platter, glass, mdf, or thin (underdamped) aluminum or zymak platter....but, nice thick aluminum, ceramic and acrylic ones seem ample buffer from extraneous energy to go matless.

Acrylic, polymer, tefnol, and other composite material are designed for mechnical impedance matching with the vinyl records for maximum mechnical energy transfer to eliminate unwanted resonance, therefore they sound better, no mat needed. Metal platters, if it comes with a mat, use it.

[Letitroll98]

The trick is to find a mat or mat material if you are a DIYer that will not suck out bass energy from the record while tracking. Almost all if not all DD tables of the past came with really hard durometer platter mats that just passed to much ambient and machine born energy through and proper mat fixes this scenario. Empire TTs have a unique method of LP support with their relatively hard mat, and those mats support the record by the outer edge only. This technique as helps keep warped LPs flatter without the use of clamps. I guess a guy has to experiment.

Wayner

A little off topic, but not too far, I have about a zillion homemade "Spot" mats.  Basically some kind of base material; paper, plastic, foam, cork, leather, or a combination of those; with various numbers and sizes of cork dots that support the record at only a few "spots".  Most of the record is in contact only with air, which allows for a very dynamic and alive sound.  Since you mentioned DIY, have you tried any of these Wayne?

Hey, I resent that. House is the only network show that I will actually sit down and watch. 

MY GF is a fan and I've tried to watch, but mostly formula writing (albeit usually well done) with fakey emergencies and constructed tension, typical TV fair, not my cup 'o tea.  After a couple of episodes the newness wears off and I'm bored.  But I'm glad you like it, I'm a fan of the actor.   

[neyloj2]

This question, as stated in my initial post, pertained to album damage and not sound quality. I'm mainly concerned about using the VPI clamp with no mat and pressing the album grooves on the platter. One response was to point and I think answered my question. If the manufacturer sells it this way leave it alone. Thank you all.