@tyray
I bought as much of the American market (and UK market for that matter) of A2900s that I could a couple of years ago, kind of accidentally cornered the market in a way as I had well over 100 of them at one point, which included a code-matched octet. At the time I was running 20 of them in my kit, 16 in the signal path at any given time. When you’re ready to pull the trigger on some let me know and I can help you vet what is a truly great pair and what is not. There are a lot of wildly off balance/mismatched pairs of GEC A2900s out there that will have no problem taking your money. That said, I had bonkers off balance pair I would use as a demo pair for my clients, which I would tell them in advance of sending them the pair, but not one person could detect the difference in listening to them.
Here’s a somewhat informative write up I once had included on some of my listing pages that details their sonics and technical details.
Enjoy,
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Hearing is believing.
You’re thinking it’s expensive. Too expensive. There’s no way it could be that good, that much better than all the other 12AT7 or 12AX7 tubes out there. Only an idiot, moron or your brother-in-law would pay a guy (who can’t even park straight) that kind of money for what, a used tube with a peeling sticker? Well, you’re right about a couple things. It is expensive, but remember, grasshopper, that price and value are different things. Ask anyone that’s bought one if it was too expensive, I betcha not a single one will say so. The only people that talk about it being too expensive are the all tubes are the same skeptics, a group largely comprised of degenerate forum fiends who’s only real contribution to society is ensuring whoever the poor soul is that mops the mouth foam off the floor of the echo chamber gets enough over time. You’re also right that it’s not the best 12AT7 out there because the A2900 is no more a 12AT7 than it is a banana. For all that the A2900 does so brilliantly, it fails us all as a banana.
The A2900 is what Mr. Royal my 7th grade science teacher would call an abundant enigma. He also called me an abundant enigma, but a story for another time. Not 12AT7, not 12AU7, not 12AX7, the A2900 goes its own way. Built like a tank because it was built for a tank, the A2900 was meant to be used during wartime, not the joystick wars we fight today, but getting hard shelled with your pants down by a Panzer twice a day kind of war. It’s highly probable someone has submitted to the business end of an A2900 in hand to hand combat. When it’s not giving your 12AT7s a wedgie, the A2900 can be found bragging about its 10,000 hour life expectancy, its ability to dissipate 3.5w of plate current vs. the 12AT7s 2.5w, and that it can take 550v of straight lightning with no chaser compared to the those 12AT7 lime lickers than can only take 300v of canned heat. The A2900 can be best defined by what it is not: colored, syrupy, overhyped, or exaggerated. This is the most natural and neutral sounding 12AT7 variant I have heard. It fully communicates all appropriate musical emotions intended by the artists without adding any embellishment of its own. This almost seems like I’m damning the tube with faint praise, but I must be clear: the GEC A2900 adds nothing and removes nothing from the sound. It facilitates a true connection between the listener and the music. This tube gets out of the way and lets the music happen in a manner unlike any other.
How do they sound? It’s the only tube other than some of the finest Siemens tubes that I have heard that can balance being absolutely transparent with being pleasant to actually listen to. One true flex of the A2900 is its almost comically large soundstage relative to other tubes; going back to those other tubes after the A2900 feels like you’re watching a concert take place in an airplane bathroom. Natural mid-range, fantastic controlled bass, a musicality that doesn’t add any color whatsoever. This tube has performed excellently in both 12AT7 and 12AX7 sockets. I’ve even pressed it into service as a 6SN7 substitute (using the appropriate socket adaptor) with superb results. In my experience, the A2900 tube will perform anywhere it is applied. It’s not a 12AT7 or a 12AX7 or a 6SN7 or anything else. It is an entirely unique creation that will lend its special quality to any system where it is installed. The Brits designed this tube with purpose, and it is immediately audible. The A2900 is highly capable, incredibly tolerant, and sonically impressive. In fact, I recommend the A2900 be used in almost any amplifier design specifying a standard 12V dual triode. I cannot be effusive enough in my praise for this tube and its quality. Top shelf, indeed.
You know what is expensive? Parking tickets.