Atma-sphere amps best power tubes


This question has been debated before on A-gon but without a clear onclusion. I wonder, is it worth it, to upgrade from stock Russian or China output tubes (6as7g), to American NOS tubes?

It seems that everyone agrees that upgrading the Atma-sphere driver tubes from stock Russian/Chinese to NOS is well worth it. This is my experience also.

I am wondering about changing the output / power tubes too. I wonder if a change to NOS is well worth it also in the output case.

It seems likely, judging from my other equipment testing.

My Audiotailor Jade OTL headphone amp uses 1 6asg7 and 1 12ax7. No surprise - it sounds better with a good NOS 12ax7 compared to Russian/Chinese stock 12ax7.

More surprisingly, it also sounds clearly better with a NOS 6as7g output tube (General Electric US NOS). The improvement is largest with the driver tube but not so much behind with the output tube. Almost 50 50.

A lot of output tubes are involved - 28 tubes in my MA-1 amps. Changing them all is costly, and so I would like to know some user experience before I go into this.
o_holter
It's a very interesting combination of input tubes . Obviously highly amp specific. If you want clean crisp almost SS sound from a 6SN7 try  old stock Hytrons, avoid the CBS Hytron.
I have to chime in on this....

I just put some Shuguang CV181-Z tubes in my AtmaSphere UV-1 pre. Best 6SN7s I have heard, and by a mile.  CLARITY.  I also run M60s and will be trying to figure out if they'll fit. They are not shaped like typical 6SN7
@ bigboltz. Does the UV-1 transmit the character of the 6SN7S  really well when you roll them?
I just asked ralph about changing over my power tubes too. Just found this thread. I hope you guys can keep it alive. I would like to experiement on diffrent tubes to push what already is one of the best amplifiers on the planet.
OK i ordered 36 RCA Power Tubes for the Nirvana Amplifier Ralph has yet to post on his site HAHA.

Soon as i get them will start on pre-conditioning and use the M60 instead.

Will report back. They being shipped over from USA to Asia. So hopefully they arrive safly.