@UntilThen @oshipao @Jim Hodgson @nykobing @DecentLevi
Thanks for all your responses on my humble Ken Rads. A better photo is below, and I don't expect that these are anything rare or unusual.
Yes, I would describe these as being quite lush in the mids, but there's also a beautiful and refined treble presence, which I think is adding to the overall sense of soundstage and transparency. The transparency I'm getting is far superior to what I got with EL3N/Chatham 6AS7G.
These were unboxed and not labelled as NOS, so definitely used. I'm a firm believer that the largest part of the battle is finding something which matches the response of the rest of one's system. I do nearly all of my listening through loudspeakers, and my PMC 23s are fairly unusual by domestic hifi standards - they're really quite flat and can sound uninspiring when paired with the wrong amplification. I think that the combo of Ken Rad 6SN7 and the Chathams just happens to provide emphasis in all the right areas to complement the PMCs. It's worth noting that while these tubes sound great with my HE400 headphones, there's nothing as remarkable going on as when I listen over the speakers.
So, I think these just happen to be right for me. I'm still looking forward to trying the EL3N six pack, although for me, E3LN/Chatham 6AS7G was nowhere near as musical, coherent or transparent as this.
Hope that's answered some questions, and emphasised that I don't think I've discovered anything special, except for in my own system
Rich.