Best New Production 12AX7 Tube, Blind Tests

[Firestorm]

12AX7-M from Groove Tubes was Shuguang, but they disappeared shortly before Fender took over (QC problems, probably). Are they back? When they were good, they were very, very good; when they were bad, etc.

[mascis]

Yeah, the box to the Groove Tube 12AX7-M says made in China, and copyright Fender Musical Instruments. I really wanted to like it but found it a bit too aggressive for me.

[Littlewyan]

Apparently its still a decent valve, although I've yet to try one. The Chinese are supposed to be really coming up in terms of quality with valves. At the end of the day it depends on how much money the men in black suits want to spend on materials.

http://www.guitaramplifierblueprinting. ... heets.html

Scroll down to the bottom of that and you'll see actual tests done on modern production valves. The GT comes out best, however I think the guy doing the tests works or worked for GT so he is probably a bit biased. Interesting though.

Edit: Also if you look at the notes at the bottom of the Output Curves or Specs for the Pre Amp Valves you'll see which valves GT relabels as their's. I.E. Tung Sol or EH are GT-12AX7R3 Valves.

[pdf64]

TAD also do a ' faithful reproduction of the legendary original Mullard
ECC83' http://www.tubeampdoctor.com/images/Fil ... %201_0.pdf

Also Watford Valves http://www.watfordvalves.com/product_detail.asp?id=2152

Any ideas about the countries of origin?

[matt h]

(deleted)

[Structo]

It's all an illusion.

That $100 Telefunken just has to sound better!

Yes TAD tubes are Chinese made but some say they are made to
their specs. Maybe the labeling is the custom part, I don't know.

I have tried their 6L6GC derivative and was satisfied.
Had one short a few years back but I think it was an isolated event.

I thought the EH 12AX7 was a bit more harsh in the high end of guitar.

But you could slap another EH 12AX7 in and it will sound fine.

I think the QC is so wacked now that you can't really generalize the tonal
descriptions anymore.

My favorite preamp tubes are vintage GE grey short plates from the 60's.

Other gem are the re-labeled organ tubes that can be Sylvania or Ratheon or other manufac.

I like to stick an old long plate in V3 PI spot depending on the strength of the tube.

[Littlewyan]

Yes I believe TAD Valves are chinese valves made to TAD's spec. They could just be tested to TAD's specs maybe.

I think you can still generalize tonal variations between brands but only to a certain extent as like you say QC is bad news nowadays. Will it ever get better? Or will it stay the same for years until we forget how good valves once were.

[Firestorm]

If you want better than usual QC, you can try the gold pin variants from JJ and Reflektor. The tubes are selected for sound, noise and microphonics, then plated. I'd rather they just perform the selection and skip the gold.

[Phil_S]

I'm quite the skeptic when it comes to anything made in China "to your spec." It is one thing for the computer I'm using, for which I suspect there is a stateside QC done and for which they extract some payback when it isn't what they ordered. That's big business exerting itself. For vacuum tubes, that's got to be small business. I imagine they make a number of "models" of the same tube...for example maybe they have the old GE equipment for the 6L6's or something. In the end, my suspicion is that the distributors like TAD, GT, and everyone else, buys large lots and culls the good ones. They figure all this into the monetary side of the deal. Imagine, you buy 1,000 tubes for $1,000. Your yield is maybe 100 good ones. Your price is $10/tube. Then you've got to get paid for culling, testing, matching, etc. $30 for a decent Chinese tube isn't too shabby. I'm doubtful there are any real custom runs as we might understand that. Just my 2 cents and happy to be proven wrong!