Oh sure, first you rag on the quality of my pictures a while back, now you are asking questions...
Yes, that is good ol' carpet on the walls - used to kill too many live surfaces in a rectangle shaped room - I do still have a lot of good live surfaces for some decent reflection and refraction - but I tried to deaden the flat parallels.
There is indeed a green cushion in the studio!!! In fact there are two! They may not be visible, but they are there!
Those pics are old - so much new gear since those photos were taken. I have some new pics of the studio, but I haven't put any of them up anywhere yet.