Tung-sol 12AX7...

[Alexo]

... and have noticed, that sometimes it's quickly dying in CF stages.

Have you tried the CF safety feature on www.valvewizard.co.uk?

[novosibir]

No, haven't tried it yet. I can't believe, that this isn't sound influencing!

Larry

[pylet2000]

The Tung Sol RI is a great tube, new production or NOS aside. And coming from New Sensor, I found it to be a shock. I was really skeptical, as the RI Mullard from them was a dissapointment to me and the only other tube they put out worth a hoot is the Sovtek 12AX7LPS (maybe only worth 3/4 hoot).

I would suggest ordering more than you actually need, as I've bought about a dozen and had problems with 2 or 3 of them. One was DOA, one burned out VERY quickly (10-15 hours tops), and one was hopelessly microphonic/noisy. Another problem I've had with these is the diameter of the tube is a little bit larger than standard. Usually not a problem, but I couldn't use these in a VibroChamp because the tube shield base was too small. I guess the VibroChamp has a relatively small tube shield base, but it was a real disappointment.

As an update, 3 failures has turned into a solid 4 gone dead!

The latest fatality was on a gig in my bass players Mesa 400+. Not like that amp is hard on it's preamp tubes. The tube has seen maybe 50 hours use, tops.

So my verdict on these is, decent tone, among the best for new tubes. But yikes, look out for failures. 1 out of 3 going dead is far too much.

A tube that I think sounds every bit as good, and has been quite a bit more durable (to date) has been the JJ long plate, ECC803S I think it is. And I'm hoping Ei starts cranking out those excellent Telefunken copies soon...

[Alexo]

Those Ei's do sound good, but side by side with an actual Tele long plate, there is no comparison, but I haven't found any tubes that compare with those!

Sorry about your Tungs!

[rjgtr]

If Ei could just lick the microphonics issues, they'd be one of my top picks.

The 12ax7EH also dies when used for the CF. I like the Tungsol 12ax7 and use it quite a bit now, but I also use JJs with them. I find that by mixing them you get a better balance and the JJs are very reliable. If the amp is darker sounding chinese 12ax7s are also a good choice for a PI or CF.

[Brewmaster]

If Ei could just lick the microphonics issues, they'd be one of my top picks.

The 12ax7EH also dies when used for the CF. I like the Tungsol 12ax7 and use it quite a bit now, but I also use JJs with them. I find that by mixing them you get a better balance and the JJs are very reliable. If the amp is darker sounding chinese 12ax7s are also a good choice for a PI or CF.

I have found that EI's work better in heads because of the long plates.

I recently had one of my Tung Sols go bad with about 50 hours on it. It started squelling like a pig.

[lo-watt]

havent tried the Tung sol...yet.

I thankfully have a bunch of good used Mullard Blackburn relabels...and they rock.

as jar as new production,i've had good luck with regular JJ ecc83's