The Stellavox TD9 is probably the most beautiful and the best tape machine ever designed. Modular, it allows recording and playback of the tape 1/4 inch (st or mono) to 16 mm film strip, stereo 2 times full runway strip 1/2 inch, etc., speed 9.5 cm / s to 76 cm / s. 18, 24 and 25 frames per second.
All this changing in a few minutes the head block and tape guides.
Unfortunately, the advent of digitization has sealed the future of this marvel that the recording quality has never really been equaled.
To my knowledge, fewer than 200 of these machines were built and their owners (myself included) would like to keep.
Still in contact with engineers Stellavox, I will try to find documentation on Stella devices (SP7, SP8, SP9 and TD9)