Higher end Tubes for Ah Njoe Tjoeb 4000

Au contraire, the 6ES8's work fine in the Ah, and they sound
great too. After much tube-rolling, I settled on the 6ES8's
and yes, I wanted to use the much more expensive Siemens
PCC88's or the Tungsrams and others-a very surprising find for
me. YMMV! Have fun.

Frogman,
The 6ES8 is a variable mu tube, not suitable for pre-amp use,
no wonder it sounded awful. The AH! uses the tubes only as
buffers, not as voltage gain devices, giving more leeway in
your choices. As long as pinout is compatible, anything goes
but how it sounds is your call. My 6ES8's are American
Amperex, and they were really cheap in comparison to the
others I auditioned. As always, YMMV. Clyde.

Hmm, very interesting. I didn't notice any overt increase in
temperature with my ES8's. I haven't done any tube-rolling
for about a year now and since I have acquired a few more
6DJ8 types since then, perhaps it's time to revisit this
scenario and see if my tastes have changed. It's all very
subjective, with amps, cables and speakers also in the mix.
Thanks for your experiences, very informative Frogman. I sure
find it strange that Melos would recommend the 6ES8 as a
suitable substitute, perhaps it's the tube itself. All my
information says it shouldn't sound good at all, but I'm not
familiar with that piece of equipment.