Recommended 12au7/5814s for Atma-sphere MP-3

IMO the best overall value for the MP-3's line section is the RCA clear top.

Priced NIB at $50-$70 per pair, it's tough to find a 12AU7 with a better QPR given the escalating prices of the highly prized Mullard, Amperex, etc.

As always YMMV.

I popped in the Clear tops last night and love them (in this unit), I just bought another pair and Mullard 12au7s from the Blackburn factory - I should be set. I also bought some RCA 6sn7GT - grey glass from the 1940s for the MP-3. Thank you all for your advice. I could not be happier with my Atma-sphere pre and amp; an incredible combination with Merlin speakers (and others I'm sure).

Bill, thanks for jogging my memory - a friend gave me a few of RCA 12AU7 Clear Tops a few years ago to try in this amp, telling me how great they were, and I completely forgot about them. I'll need to give them a shot...

Joe,
Thanks. In response to your first post, earlier this year I purchased 2 pair of the Amperex 7316/ECC186; one pair halo and one pair D getter.

First of all, I didn't need them. My tube inventory has reached a ridiculous number, probably close to 1,000, most of which will never be used. I plan on selling many of these within the next 2 years in order to be at a "manageable" level. Thank goodness most of them were purchased prior to the current "run" on NOS and at really stupid prices e.g. 6922 Bugle Boys for $15/pair and Sylvania 6SN7 Bad Boys for $20/quad etc. Of course this was back in the 70's and 80's.

Secondly, the Amperex tubes are great, perhaps the best iteration of the 12AU7 I've heard. If money isn't important it probably doesn't get any better. However, having heard them in a number of amps and preamps, I would not spend that much money again. There are other 12AU7 that perform admirably for much less.

YMMV

While I understand that to some extent, every tube matters, do the 6sn7s make as noticeable difference in the MP-3 compared with the 12au7s? That is, are these slots worth spending NOS money on?

On the M-60s, do the front and back 6sn7s (V1? V2?)get equal billing for NOS upgrades, or are the V1 spots more sensitive in terms of impacting the sound? Additionally, my understanding is that the V2s in the M-60s in the back have to be GTA/Bs to handle the voltage.

When does the bidding start on the Bad Boys?