CuSat 50 or Libran

Success!
   I bought a Neutrik 6.5mm socket and four banana binding posts. It was simple enough to wire it as per Graham’s instructions, and I installed it all in a little ABS Jiffy Box after drilling five holes. Job done.
Thanks Graham.
Mick.

I would make a habit of turning all dials down before you switch between different headphones or speakers, to minimise any risk of accidentally damaging any device you've got connected, say for example you switch outputs quickly and make a simple error. Let me know how you get on and what you choose to drive. If I recall correctly, I used 8-9 o'clock on the Proprius for driving the sensitive high resolution HD800, 9-10 o'clock for driving HD540II/HD560II (so HD250 would be the same) and 12-3 o'clock for the K1000. 12 o'clock is perfectly adequate for the K1000 but I heard no hiss at 3 o'clock either and you don't have to turn the Majestic dial up as much. For my high resolution Mark Audio P drivers, I set the Proprius dials at 12 o'clock or lower. As I move from 12 towards 3 o'clock, I personally hear some low background hiss from them which I find quite intrusive especially beyond 3 o'clock so as I personally like hiss as inaudible as possible, I choose to keep the Proprius down as much as possible and crank up the preamp level (Majestic or Bitzie).  I was very pleased with the sound quality and felt that I no longer needed to have a headphone amplifier such as the Solo, as all my chosen devices were suitable loads for the monoblocks. The K1000 is the only headphone I have these days so I'm simple but I do have the freedom of using something like the HD250II from the monoblocks if needed. This is the headphone that Graham used to make the Proprius, after all.

It's definitely worth a little DIY or contacting John Cadman for a suitable cable. I've driven my LCD2's from the Proprius amps in the past and found the sound very dynamic and full. To be fair the Solo ULDE puts out enough for quite loud listening levels.

Ash and Mick's tip is not just on headphones. Backing off the level control on the Proprius amps opens up the the range of usable settings on the Majestic level. I have fairly sensitive speakers and sit quite close of them so found late night listening ends up being right at the bottom of the Majstic volume pot otherwise.