Used tubes question

Finding TungSols in matched pairs will be hard to do(no- I can't cite a good source), but worth the effort if you can locate some that are low enough noise for a preamp section. Depending on what half wave rectifier you are presently using(ie: Chinese), you should have an audible improvement by installing say, a NOS RCA. They're selling for around $5 now, so the experiment will be cheap. Too bad there aren't any Mullards out there.

I only use NOS tubes and there are big differences between these even in the Mullard variety. I switched from Phillips miniwatt 6GW8 for my Rogers Cadet III to English Mullard NOS. I am finding these harder to source but I hunt them down. Massive improvement. Good NOS rectifiers will improve things further. Lebens are respectable little amps and contrary to common misconceptions quite robust. The only thing is the Leben fixed or cathode bias if the latter pop em in and enjoy. Cheers

Wow again. What a difference with the Sylvania 6CS7's. It is more dramatic then when I added the xf2's. BTW-The CS-600 is more than respectable and more than little :-).

Those that don't experiment with NOS tubes, just don't know what they're missing. Enjoy your music!! =8^)