Insane tube prices Genalex 1300.00 12ax7's ????

[SteveinTempe]

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... =3284&rd=1

[Plexi]

Oh My!! and yes there are bidders.. And i thought the tubes i had were pricy,I bought out an old TV shop, and had some number 50 tubes And 2A3 . And some old NOS VT and Jan tubes.. Sold them all to Antique electronics. I have seen some old hifi amps posted for around 75,000
But this one you posted...tops all i have seen just for a pair of 12AX7s

Richie

[Dai]

I don't know how correct this is, but when I looked for info on those on the web (tube sites, etc.), those were supposedly just the same thing as a Mullard, but given a fancy presentation as a marketing thing. IIRC, there was a Red Bank version of the 12AX7, so perhaps that would actually justify such a high price, with the overbuilt construction and materials typical of the Red Bank series of tubes.

Dai

[Wannatone]

Just check the bid history for the current 0 feedback bidders.
Btw, some Chinese guys appear to pay any price...

Adrian

[Dai]

Well it doesn't look like anything special construction-wise. No extra mica supports, only single getter support. There does exist for some people the train of thought that the older and rarer the tube is the better it will sound. I guess it's easier and maybe more prestigious to be able to buy rare tubes and switch them in and out of your stereo equipment than it is to learn how to make modifications. I kind of think that Eric Barbour (of VTV fame) is right and there are probably lots of less commonly used/popular tubes that would make great audio tubes.

Dai

[SteveinTempe]

Yeah like the 12av7 is a cool tube
I just bought 100 of those for 25.00

They sound killer !

[zaphod_phil]

Well it doesn't look like anything special construction-wise. No extra mica supports, only single getter support.

If it's been made by the General Electric Company (aka Marconi or M-OV) as I suspect, the differences may be very real, but located deep inside of the tubes. With their Golden Lion branded tubes the differences were things like chemical purity and quality of emissive materials and electrode platings, plus very accurate grid spacing. These guys took a lot of pride in how they built their valves. And it's these small details that make all the difference for the Audiophiles. I recently had the privelage of meeting Dr Barry Vyse, who used to be the company's CEO before they got shut down - a very interesting person to talk to.

[Dai]

I suppose that could be true, or some audiophile types guess that they were part of the normal production line but chosen after a stringent selection process. Appearance-wise, it just looks like a regular Mullard 12AX7/ECC83. Looking at Red Bank tubes seem to give a sense of what overdesigning looks like--extra stiffening rods, spacers (ceramic instead of mica for RB), high temp glass, ceramic base, ceramic sleeve for the heater, etc. In some of the com and MIL versions of more common tubes, you can see a bit of the same in extra mica spacers, stiffer looking build inside with extra supports or whatever.

Dai

[zaphod_phil]

Those features you're describing relate more to physical ruggedness than tonal quality. Typically the more rugged valves were made for military usage, but are now very popular for guitar amp usage as they tend to be less microphonic and longer lasting under the stressed conditions found in gigging guitar amps. The other inner factors of chemical purity and quality of emissive materials and electrode platings, very accurate electrode spacing, etc are the ones that provide the tonal purity. No doubt some selection may have been carried out, but this is a more common practice these days, with the less strict quality controls of Eastern European and Far Eastern producers. GEC Marconi were big rivals of Mullard, and both companies made consistantly good valves, due to having perfected their production and quality control systems.

[Dai]

Well yeah, I am talking about more from a technical perspective and how un-special the tube in auction appears to be. Subjective tonal qualities is a completely different ball game. Lots of people seem to like the sound of Ei 12AX7s (audiophiles and guitar players) for example, but as a tube it's pretty crappy. Poor quality control, inconsistent, short life, etc. But there aren't any organizations I gather that ensure tubes meet the specs and no longer a huge market so not much competition as before. I have no argument about GEC, Mullard, etc. making excellent tubes. That seems to be the general consensus for anyone into tubes. Some tubes like Mullard GZ34s and GEC KT66s are known to last decades apparently in some cases. There is no way a modern Chinese or Russian version will last as long (or at least I SERIOUSLY doubt it). As far as the chemicals, alloys, plating, grid winding, etc., I'm pretty certain that the makers of the Red Bank series of tubes would have paid attention to those those aspects too. I don't see how they would overlook some aspects while making the others completely extravagant. In case you don't know these were a series of overdesigned extravagant tubes built for the U.S. military. You would've been able to buy Gold Lion as long as you had the money but not the Red Bank stuff back then. And they probably cost much more to make. As far as tonal qualities, they seem to differ depending on tube and application. The 6V6 version got the top rating for audio use but not a very good review in a guitar amp, for example (in VTV mag). From the little that I've read, I'm not really that surprised at the higher quality (in general) of tubes back then. They were so much more important, and a staple of electronics. The military needed them for com equipment and whatever else, so they had to have good tubes. A vastly larger consumer market, radios, then hi-fi, TVs, and whatever else (ham radio?) existed. So there was a time when the best university grads and talented people went to tube manfs., (metallurgists, chemists, whatever) so it's obviously a very different situation now (unfortunately for us tube lovers).

Dai

[zaphod_phil]

As far as the chemicals, alloys, plating, grid winding, etc., I'm pretty certain that the makers of the Red Bank series of tubes would have paid attention to those those aspects too. I don't see how they would overlook some aspects while making the others completely extravagant. In case you don't know these were a series of overdesigned extravagant tubes built for the U.S. military.

I am familiar with the Red Bank tubes, and agree with what you say about them. I was merely trying to point out that the parts of a tube which make the most difference in tonal quality aren't always the ones you can see. As I'm into distorted guitar amps, most of those benefits in tone are probably of little interest to me anyway...