12ax7 valve sound help.

[s.thomas]

Hello all,

Im looking at replacing the stock 12ax7 tube in my SET amp. I would say its quite flat and brash sounding.

Does anyone have any experience on which 12ax7 valves have a wider soundstage, better instrument separation etc; I find with my current 12ax7 the mids can sound "hard". Basically I think its just a cheapo tube. Im guessing a valve will sound different in different types of amps, but some general guidance would help considerably. Please !

Thank you.

Stephen

 

[i_should_coco]

What makes you think it's the tube at fault and not just the way the amp sounds?

 

[s.thomas]

Kind of a chicken an egg situation ! Lol !

 

[i_should_coco]

Indeed. I suppose it's cheap enough to try....

 

[s.thomas]

Yes, only needing a single 12ax7. Worth a go ! Could even buy a few different ones to test - if the price is right.

 

[Cable Monkey]

The real benefit of the 12ax7 is that there are plenty of tubes that will work in its place. You can go for rare 'Old Stock' tubes, or something brand new from Psvane. You can also choose more carefully from modern standard tubes which will be quite cheap. Look up the list of alternatives to the 12ax7 too. Of course they might not make the difference you are looking for but it doesn't hurt to experiment.

 

[silencio]

Stephen, there are numerous threads on the Wam regarding valves , 12ax7/ecc33 including. Why not check them first. Here are a few - NOS Telefunken ecc83, NOS Tungsram ecc83, NOS TungSol 12ax7, NOS RFT 12ax7. Ne ones - TJ Full Music 12ax7, JJ ecc80s gold pin.

 

[s.thomas]

Silencio, yes I have searched for general 12ax7 info here, but my post is specific in that Im looking for a certain character of tube. Infact online there are many hundreds of reviews for tubes, but I respect the opinion of this forum as it has served me well in the past. Thank you for your suggestions and I will take a look at those now.

 

[June]

I've tried 1960's Amperex (Bugle Boy) ECC83, 1970's Brimar ECC83, Ei (pre-war) ECC83, Groove Tubes 12AX7, 1960's GE 5751 grey plates, 1950's GE 5751 black plates and Sylvania Gold Brand 5751 (grey plates with gold pins).

In my system, most of the time I'll take a 5751 over an ECC83 / 12AX7.

However, if you want a specific recommendation then a 'full fat' tube you could try is an early 12AX7 that Philips made in their Eindhoven, Heerleen, Sittard, Brussels and Copenhagen plants in 1953.

They are usually labelled as RCA or CBS Hytron (not many were labelled Amperex at that stage) and have Delta 0 mCA (Feb 1953) or Delta 1 mCA codes (March 1953); the 'Delta' just means they were made in Eindhoven but it doesn't matter which plant they originated from because at that stage they were all identically constructed, used the same materials, same chemical processes and were overseen by Philips company personnel).

To my ears they sound far more 'organic' and 'earthy' and have more bass than your more familiar Amperex longplates (Philips later made modifications and started labeling more of them as Amperex with mCb, mC2 etc...codes; further modifications resulted in the long plate Amperex Bugle Boy but there's no comparison to the 1953 tubes IMHO).

They're not cheap though. You could try a Bugle Boy (plenty about and reasonably priced) and if that's the the right direction for you then go for the earlier Philips 12AX7.

Having said that, and as has been said many times before on similar threads, the final sound is more down to the circuitry than the tubes you use.

My 2p of course.

Good luck with your tube adventure.

 

[s.thomas]

A really detailed and generous reply June, thank you. That was exactly what I was looking for. Its great there are so many varied tubes out there and I think I will thoroughly enjoy some lengthy rolling time ! the Philips/RCA/CBS and the Amperex Bugle Boy are on my radar now thanks to you.

 

[AlanB]

If you want to smooth things out - you said it was brash sounding - then you won't go far wrong with GE 5751's. Cheap at Langrex too. If that doesn't do the trick it may well be the amp.

 

[s.thomas]

Thank you AlanB. I have infact ordered a 5751, so fingers crossed. I also hadnt heard of Langrex - wow, what a great site and very reasonable prices.

 

[Tel]

If you haven't heard of Langrex then maybe you haven't seen this thread

http://www.hifiwigwam.com/showthread.php?5163-Valve-info

 

[s.thomas]

Cheers Tel. What a helpful bunch, as always ! :^

 

[parmeko]

Hello

try the CV4004 or ECC83 long plate, I have been given 4 pieces perfect and working if interested thanks Rob

 

[spook]

Recently replaced some chinese 12ax7's with a pair of nos Brimar's in my power amp. Made a noticeable improvement. Not too expensive so well worth trying if you fancy some tube rolling.

 

[s.thomas]

Hellotry the CV4004 or ECC83 long plate, I have been given 4 pieces perfect and working if interested thanks Rob

Recently replaced some chinese 12ax7's with a pair of nos Brimar's in my power amp. Made a noticeable improvement. Not too expensive so well worth trying if you fancy some tube rolling.

Thank you both for those suggestions. I have replaced my 12ax7 with a Sovtek LPS tube (not chosen for character, purely due to price) and already Im hearing much clearer and better defined sounds. Ive bought mostly new tubes to begin with - Gold Lion, JJ 5751 & ECC803S, three that I will hope will smooth things out a little.

 

[silencio]

Check out the NOS RFT ecc83 for deeper and better controlled bass. Pretty reasonable prices too.