New production 12AX7 for guitar amps...like to hear what everyone likes!

[dcollins]

Originally Posted by Wavebourn

Did you gentlemen try trimpots instead of cathode bias resistors? Such a way you may tune any brand of 12AX7 tubes to any sound you wish (hard, smooth, rough, bright, dim, sweet, sour, ____), much cheaper than buying exotic tubes. No magic at all. The same glass, metal, vacuum, and slightly different geometry causes slightly different characteristics.

Wouldn't it be great if it really worked like that?

Think how easy life would be. Chinese 12AX7? Just 'dial in' the Telefunken cathode resistor and voila!


DC

[Wavebourn]

Originally Posted by dcollins

Wouldn't it be great if it really worked like that?

Think how easy life would be. Chinese 12AX7? Just 'dial in' the Telefunken cathode resistor and voila!

Yep. When tubes from RCA and Telefunken were cheap and available a life was easier, since all of them were similar like twin brothers, and all tubes if were alive performed the same way as they did on the table of the gear designer. Regimes had to be tweaked at once, during design. No further adjustments were needed: just plug in a new tube, and get the same currents, voltages, curves! The same sound!

Now when spread of parameters of vacuum tubes is wider than barn gates you have 2 options: either to roll tubes in order to find one that match better what was used by original designer and by a factory, or tweak regimes of tubes you have. Both ways are valid.

However, there is one more way: to use DC feedbacks like I do in my Pyramid amps, to automatically adjust regimes no matter what brand and age of tubes are inserted. But when vintage gear was designed such tricks were not needed: all RCA and Telefunken tubes were very close to specs. So, you have two ways to get needed regimes: either to adjust resistors, or to find right tubes. In both cases the result will be the same: identical curves for the identical sound.

Originally Posted by Puffer Fish

But I have had the best luck with the JJs.

Me too. I always liked Tesla tubes more than Soviet ones: they were sometimes available in USSR.

[on a mission]

I like the Sovtek 12AX7 we put them in a fender hot rod deluxe with
Sovtek 6l6WXt+. Very punchy and freakin loud. Though it's hard to tell
how clean they are because the speaker has a little fuzz to it.

[Voc Rock Guitars]

My absolute favourites are

12AX7LPS (Long plate Spiral). Fantastic Bandwidth with no particular emphasis but really smooth. One of the best current prod tubes today Me thinks.

12AX7 Tungsol Fairly low gain but plenty of bottom end thump.

ECC83S JJ High gain works really well in some amps for rip solo leads. Nice smooth and emphasised mid range. Not too good for bass frequencies though.

All our tubes are tested thoroughly for noise, Gain and Trans.

[Wavebourn]

What do you mean by Fantastic Bandwidth?

[Voc Rock Guitars]

Wide Bandwidth. Good High frequency detail and good very low bass....

[mobius.media]

Originally Posted by Voc Rock Guitars

Wide Bandwidth. Good High frequency detail and good very low bass....

And which one is that?

[Voc Rock Guitars]

The Sovtek 12AX7LPS (Long plate Spiral element)... Extended high and low frequency. One of the best pre tubes Sovtek are making today. My opinion of Course.

[htieksppircs]

This catagory is too broad. Depends on the tube type depends on the amp. For instance, I'm not crazy about JJ 12AX7s, but their EL84s rule! Like the tung Sol 12AX7, a bit bright but never annoying. The Mullard EL 84s seemed slow and lifeless to me. Tung Sol 6V6 very nice tone, very even, but slightly lower output. Haven't tried the JJ 6v6.