Bit unconventional but sounds good to these ears ................... :)

[Pigmy Pony]

Yes indeedy, they are Transmission Audio M1i"s. https://share.google/NCw7Xdzg30mJbtM0E As you say, very rare and highly regarded. They are the bit of kit that I have owned longest.

Up where, is up in a part loft conversion. About a 1/4 of it has been converted.

I trust that 1/4 includes the actual roof