On owned ID TT;s I have had a very pleasant surprise from a 5mm Forex Foam Material.
The same surprise has also been discovered with the 5mm Forex Foam in use on owned DD TT's
A Friend was quite impressed with the same 5mm Material used on their BD TT, where I gifted them my spare Mat.
The owner of the BD TT, now uses the 5mm Mat on their SP10 R as well.
I bought 2 x 3mm and 2 x 5mm Forex Foam, produced as a TT Mat, where including delivery it was approx' £30.
At the time of Purchase the Material, it was described as being the same as a Brand known as DAT Mat, which was approx' £100 and the Mat thickness I can not recall for this product.
The 3mm was able to change the Sonic, but also impacted on the SQ.
The 5mm is a different impact, every thing that is extremely attractive is maintained or slightly improved, even when there is a noticeable hint of Richness of Tone with the 5mm used in comparison to a Metal Mat.
The Forex Foam 5mm will work with the Concave Platter.
If moving away from Richness of Tone is attractive, then Metal Mats are able to produce this perception.
In my experiences, the AT 666 Vacuum Mat is the one to produce the perception of being most Transparent/Lean of used Metal Mats.
The Tenuto is next in perception of Transparency/Lean.
The AT 677 Duraluminium Technihard and Micro Seiki Duraluminium are perceived as a hint towards Rich Tone when compared to other Metal Mats.
The Micro Seiki being 8mm Thick, is perceived as the one with the most perception of a Rich Tone, with my experiences of Metal Mats used.
Do not let anybody try and steer one into thinking Mats don't create a perception of Tone.
Do let in the notion, that a Mat of a certain type can be quite a bad inclusion.
As there is the materials, or interface for the material, that creates a end sonic, where much of what is attractive is effected to the point it is perceived as being very deficient and unwanted.
The downside is to learn where the differences are to be found, does mean Differing Materials, Differing Materials Thickness are needing to be experienced in use in the environment the TT is set up in.
The upside is, when the correct interface is found, there is a deep satisfaction to follow.
A lot of Though has gone into what the TT and TA is to be seated on.
Similar thought is also required to discover what is the best for the Vinyl, as the Source Material and Styli as the Data Extractor to be seated on.