Hi Dgob,
I'm sending my Mat2 back to the factory for an exchange because mine had a little dent that looks like a gap in the graphite. It'll probably take about 10 days for the exchange process.
At the moment, I have the Audio Technica AT-600 Ceramic TT Mat on the Mambo. This is a mat that I haven't spend much time with. I haven't done A/B comparisons with the Mat2, but at least in my system, it compares vavorably to the SAEC SS-300 mat.
I listened to Diana Krall today and there is no shift in her voice that I could detect. I've been to one of her concerts and her voice via the Mat2 seems to have the same pitch as with her voice in the live concert I went to few years ago. The same I could say about the Mat1, as far as I can remember.
There seems to be an emphasis on the mid-range with either the Mat1 or the Mat2, when compared to the SAEC and the Audio Technica mats.
Best,
iSanchez