Anthem Pre 2L tube rolling question


The Anthem Pre 2L uses four matched 6922s. I've swapped in plenty of varieties, and now have found some that sound really good (Valvos) but were pretty expensive. I've been swapping whole quads in and out.

Is it ok to use one pair of "good tubes" and one pair of stock tubes (or other ordinary tubes) in combination and still get positive effects? Of course, this way my quad of "good tubes" will last twice as long.

Just curious - of course I need to know if the good pairs should be on the front or the back.

Anybody with experience on the Pre1L or Pre2L can answer?
dozer
Yes, put the good ones in front. If there is a difference, this will be an improvement, although not as much as with preamps such as the AI M3a where 2 are for the linestage and 2 are for the phono. That's what SF used to recommend. I swap out all 4, but I dont get real exotic. Tube life in these preamps is pretty long, not at all like the AI preamps, so I don't worry about how long they last.

Paul
I used to own the Pre2L and have upgraded to the Sonic Frontiers Line 2 preamp. It is the rear tubes that have the greatest effect on the sound. This was conveyed to me by Kevin Deal (where I bought the Pre2L and an Anthem/Sonic Frontiers dealer) and he reiterated this at another audio forum. I believe he said the rear tubes will get you 80% vs using the same tubes in all 4 positions. My personal experience is that life is too short, and I use Siemans 7308's in all 6 positions of the Line 2. BTW, the Pre2L is an excellent preamp and very underated, as long as you don't mind living with the sensitive remote volume control.
Hmm, that's a problem because I thought for sure Kevin told me the opposite, unless we arent talking about the same front. I could be mistaken, and as I said, I just swap all four. I'll see if I can raise him.
I've been wondering the same thing for my Pre-1L. I'm about to start tube-rolling and would like to save time/money by swapping in pairs rather than quads. Are the two pre-amps the same as far as tube position?
Paul/Yowser: Could one of you break the tie by saying "I'm 100% positive that I'm the one who heard Kevin Deal right"?

Back pair = closer to rear panel. Front pair = closer to front panel.

Thanks. Dozer
Hi there..

In the Pre-2L and Pre-2LSE both pairs of tubes are voltage gain. One may be more pleasing to upgrade than the other for you. There are no rules to that. Try it for yourself.

In the Line 1 and Line 2 we seemed to get the best results by changing just the rear pair. This in an effort to get the most bang for the buck and not do all six tubes.

The good news is that both preamps are such that you can mix and match. Just make sure that each pair are the same. So you can put Russian 6922 in one position and 7308, 6922, 6DJ8, CCa, etc in another.

Regards,

Kevin Deal