Best 12AX7 for phono preamp

[aussievintage]

I know there are heaps of reviews and discussions out there already.  One problem is, I found myself reading comparisons that were 10 years old and  more.  I am looking for 12ax7s to go in my phono preamp which uses 2 x 12AX7s with a passive RIAA between them, and then a 12AU7 output buffer.

 

So,  when I look at some local suppliers I see quite a choice of new 12AX7s.    Being for phono preamps, I am leaning towards something with low microphonics and noise.  Noise is something that doesn't often get mentioned.  I mean that low background hiss or rushing sound you get when you are using lots of gain in a circuit like a phono preamp. I might also prefer gold pins - maybe.   

 

I have Electro-harmonix and JJ already, the cheap versions, so looking at what else there is.   I see Genalex Gold Lions being well reviewed, and getting a premium price.  I see Tung-sol Gold pin at a cheaper price, and claimed to have low microphonics (due to short plates?).  Lots of other choices.  I guess I am leaning towards the Tung-sol gold for the first position in my phono preamp, mainly because of low microphonics.    

 

What's your preferences? What do you use?

[doogie44]

The input tubes in a phono stage are the most sensitive and so you need matched and low-noise tubes for preference. 

 

In the world of tube rolling and especially the 12AX7 you do get what you pay for. While the modern varieties of valve sound 'OK' they can't compete in my opinion with the qualities of NOS (New Old Stock) types. I note that some preamp and phono preamp makers use JJ tubes, so presumably these have excellent quality control. The other Chinese or Russian tubes leave something to be desired. An exception may be the Psvane and Shuguang Chinese speciality tubes (Black Treasure and such); these do cost much more and bring up the question 'if you're willing to pay for those why not buy NOS from a reputable dealer?'

 

Unfortunately NOS tubes are expensive but not out of reach. They make a fantastic difference to your overall sound. It's a premium cost over buying ordinary tubes; to my mind, totally worth it. I don't personally wish to buy a matched pair of NOS Telefunken because that's 'very' pricey. YMMV regarding cost.

 

As a broad generalisation the Mullard and Brimar qualities have a somewhat lusher and warmer presentation while the Telefunken and Siemens qualities emphasise clarity and detail. It's a matter of tonal preferences. When I finally settle on a particular make of valve I often regret the expense of buying lesser kinds--that I can't bring myself to use having heard the best.

 

Brent Jesse discusses the merits of 12AX7 tubes here (I find his comments accurate, service impeccable, and his prices high!):

http://www.audiotubes.com/12ax7.htm

 

In the past I have bought NOS from dealers in business for the long term and not 'straight off eBay' (buyer beware). Testing results are essential there...

 

Note that the 5751 tube is a substitute for 12AX7, giving a slightly lower output and a greater range of valve types to choose from.

 

Currently in my 12AX7 amplifier front end I have low-noise matched Sylvania NOS 5751 gold pins, or Siemens NOS; in my preamp phono section, as an example, I use 12AT7 (not a substitute for 12AX7) either Mullard or Telefunken NOS. 

 

If at all possible you might be able to ask an SNA member to insert some NOS valves into your system so that you can see what all the fuss is about. Once heard, never forgotten, I say

 

Just my 2c worth

 

 

 

[Gryffles]

42 minutes ago, aussievintage said:

I know there are heaps of reviews and discussions out there already.  One problem is, I found myself reading comparisons that were 10 years old and  more.  I am looking for 12ax7s to go in my phono preamp which uses 2 x 12AX7s with a passive RIAA between them, and then a 12AU7 output buffer.

 

So,  when I look at some local suppliers I see quite a choice of new 12AX7s.    Being for phono preamps, I am leaning towards something with low microphonics and noise.  Noise is something that doesn't often get mentioned.  I mean that low background hiss or rushing sound you get when you are using lots of gain in a circuit like a phono preamp. I might also prefer gold pins - maybe.   

 

I have Electro-harmonix and JJ already, the cheap versions, so looking at what else there is.   I see Genalex Gold Lions being well reviewed, and getting a premium price.  I see Tung-sol Gold pin at a cheaper price, and claimed to have low microphonics (due to short plates?).  Lots of other choices.  I guess I am leaning towards the Tung-sol gold for the first position in my phono preamp, mainly because of low microphonics.    

 

What's your preferences? What do you use?

The Sovtek 12AX7LPS is the best new production IMO. Long plate and spiral filament.

 

If the 12AX7 are the first gain stage then talk Jim McShane and he will test the noise level for you and supply the better ones. This is what I did when I had an Aesthetix Rhea and it worked well.

[unclekanus]

Word on the street is that JJ is about to release a new frame grid tube, a-la Telefunken ecc803s.

That would certainly provide an interesting current production option, especially if they approach the quality and longevity of the TFK. I have some vintage Tesla e83cc frame grids that sound great for phono duties. Tried all manner of 5751's in that phono but 12ax7 types seemed to work better into the passive eq.

[aussievintage]

1 hour ago, doogie44 said:

As a broad generalisation the Mullard and Brimar qualities have a somewhat lusher and warmer presentation

I have one Mullard Ecc83.  Sound is one thing, but this particular one is prone to pickup hum.  Not so much a problem as I used shields.

 

1 hour ago, doogie44 said:

Shuguang Chinese speciality tubes (Black Treasure and such)

I haven't tried the specialty ones, but I do have some Ruby tubes and one National, which apparently come from Shuguang.  They actually look very different internally - seem to have more structure.  I also find them to be low noise and low microphony.

 

1 hour ago, doogie44 said:

Just my 2c worth

 

much appreciated

[aussievintage]

1 hour ago, Gryffles said:

If the 12AX7 are the first gain stage then talk Jim McShane and he will test the noise level for you and supply the better ones. This is what I did when I had an Aesthetix Rhea and it worked well.

I hadn't considered specially selected tubes.  Worth doing for difficult situations.

[aussievintage]

9 minutes ago, unclekanus said:

Word on the street is that JJ is about to release a new frame grid tube, a-la Telefunken ecc803s.

That would certainly provide an interesting current production option, especially if they approach the quality and longevity of the TFK

Yes Teles have quite the rep.   Could be good.

 

10 minutes ago, unclekanus said:

Tried all manner of 5751's in that phono but 12ax7 types seemed to work better into the passive eq.

They are a bit lower gain too I think.   I am experimenting with a passive "preamp" so I really need normal gain.

[Wayne Elliott]

I replaced some junk Chinese no-name tubes in a Phono stage with a matched quad of Psvane 12AX7-11. Yes the Psvanes were better as they would want to be. They are relatively quiet, although havn't compared to any NOS tubes. I have a quad of  Electro Harmonix 12AX7 in another component, I've been intending to do a comparo with in the Phono stage, I'll see if I get time to do in the next week or two.

[aussievintage]

1 hour ago, initforthemusic said:

Yes the Psvanes were better as they would want to be. They are relatively quiet, although havn't compared to any NOS tubes.

 

Something I have noticed.  Some of the less microphonic and quieter valves have tried, have a similar construction.  As you look inside 12AX7 and other tubes, you notice they are not all constructed the same way.  

 

The Psvanes have a triple mica setup, and have a shield between the two triodes, that actually wraps around at each end in the opposite direction forming an S shape when viewed from above.  This setup would lock the construction together very solidly.  You can see the wraparound end in the first picture below - it's the silver bit right behind the logo.  Now, I am guessing because of the heritage of Psvane,  it is not surprising that Shuguang tubes and the cheap guitar oriented resellers, like Ruby tubes,  use the same construction in some of their valves like the AC5.  You see the same in the the 12AX7-Ts from Shuguang.  The older plain Ruby 12AX7A tubes I have also have this construction. 

 

They are all related to Shuguang so no surprises.  I am just saying the construction method is fairly unique and results in a good solid quiet tube, even in the cheap ones that I have tried.

 

 

 

 

 

[Guest Muon N']

12AX7LPS are low microphonic, but low microphonic does not guarantee a subjectively great sound.

 

That Ruby tube is a rebranded tube IMO, and might even be made by Psvane So I wonder if you are comparing virtually the same tubes there.

 

Edited October 3, 2019 by Muon N'

[Ittaku]

These guys have one of the best grading systems around that specifically checks for noise and microphonics. Unfortunately they only ship to North America, and then won't even let you buy it from Australia and ship to a NA address. If you know someone in the USA who can buy them for you, you can get something that's guaranteed to be quieter. Sure some production types are more prone to microphonics than others, but even within them you can grade them and get a sane affordable valve.

https://www.upscaleaudio.com/collections/preamp-tubes/12ax7-ecc83-cv4004-5751

 

Alternatively, I've had very good results by buying my preamp valves directly from the grantfidelity shop who will deliver to Australia, but they cost proportionately more.

http://psvanetube.com/wordpress/purchase/shop-by-tube-model/12ax7/

[aussievintage]

12 minutes ago, Muon N' said:

12AX7LPS are low microphonic, but low microphonic does not guarantee a subjectively great sound.

 

That Ruby tube is a rebranded tube IMO, and might even be made by Psvane So I wonder if you are comparing virtually the same tubes there.

 

 

My belief is that Shuguang make the tubes that Ruby rebrand, and, at least to start with grew out of Shuguang's R&D department.  Not sure if Psvane still get Shuguang to make all the stuff or not.    

 

I haven't tried Sovtek in a hifi amp that I can remember.  The LPS  has been around a long while IIRC.

[Ittaku]

2 minutes ago, aussievintage said:

I haven't tried Sovtek in a hifi amp that I can remember.  The LPS  has been around a long while IIRC.

I fell in love with Sovteks years ago in my first ARC amp. They have their place, and I use a mix of Sovtek, Tungsol, and PSVane tubes, but note, I do not use any 12AX7s so this is just generic opinion from their other valves.

[aussievintage]

14 minutes ago, Ittaku said:

These guys have one of the best grading systems around that specifically checks for noise and microphonics. Unfortunately they only ship to North America, and then won't even let you buy it from Australia and ship to a NA address. If you know someone in the USA who can buy them for you, you can get something that's guaranteed to be quieter. Sure some production types are more prone to microphonics than others, but even within them you can grade them and get a sane affordable valve.

https://www.upscaleaudio.com/collections/preamp-tubes/12ax7-ecc83-cv4004-5751

Yes, certainly choosing the best of a standard production run should get you nice valves.  It would be a nice service to have.

 

15 minutes ago, Ittaku said:

Alternatively, I've had very good results by buying my preamp valves directly from the grantfidelity shop who will deliver to Australia, but they cost proportionately more.

http://psvanetube.com/wordpress/purchase/shop-by-tube-model/12ax7/

I was just nosing around that shop earlier.  I love their branding and packaging.  Shouldn't allow myself to be sucked in by stuff like that but, yeah, looks nice.

[Guest Muon N']

Just now, aussievintage said:

 

My belief is that Shuguang make the tubes that Ruby rebrand, and, at least to start with grew out of Shuguang's R&D department.  Not sure if Psvane still get Shuguang to make all the stuff or not.    

 

I haven't tried Sovtek in a hifi amp that I can remember.  The LPS  has been around a long while IIRC.

Yes, but now most tubes of well known brands are all made by New Sensor, they bought the names and rights to names like Mullard, Sovtek, Svetlana, and the list is too long to name...you name a brand It's likely held by New Sensor since 2000 or 2001.

[aussievintage]

1 minute ago, Muon N' said:

Yes, but now most tubes of well known brands are all made by New Sensor, they bought the names and rights to names like Mullard, Sovtek, Svetlana, and the list is too long to name...you name a brand It's likely held by New Sensor since 2000 or 2001.

 

and Shuguang isn't still around?  The internals of those "new" Mullards and things are not like the Shuguangs and Psvanes.  Might still be separate manufacture.

[Guest Muon N']

1 minute ago, aussievintage said:

 

and Shuguang isn't still around?  The internals of those "new" Mullards and things are not like the Shuguangs and Psvanes.  Might still be separate manufacture.

Yeah, they are a Chinese make of course not owned by New Sensor, I did say most..and as far as I know Shuguang is only a relatively new brand regarding being well know in the west?

 

New Sensor owns names like Sovtek, Svetlana, Mullard, Tung Sol, JJ, Electr-harmonex.

[Guest Muon N']

Personally, the ones I have heard that I liked are all NOS and ones like Mullard, Philips, Amperex (bugle boys) ect'.

 

But we all like different things, and it is largely dependent on the system, we never hear a tube in isolation I actually went with octals in a phono stage when I had a TT, 6SL7's to be specific.

 

Some NOStbesw can be noisy but it is not representative of all, but that's a gamble we take when is search of a sound, we some of us.

Edited October 3, 2019 by Muon N'

[aussievintage]

4 minutes ago, Muon N' said:

New Sensor owns names like Sovtek, Svetlana, Mullard, Tung Sol, JJ, Electr-harmonex.

That's why I was a little hesitant about Tung-sol.    I don't think much of this re-using brand names thing. 

 

The old Svetlana was a good brand - of have a pair of lovely EL34s from them.

[Guest Muon N']

1 minute ago, aussievintage said:

That's why I was a little hesitant about Tung-sol.    I don't think much of this re-using brand names thing. 

 

The old Svetlana was a good brand - of have a pair of lovely EL34s from them.

I'm with ya' there, I run NOS Svetlana EL34 Winged C's

[aussievintage]

2 minutes ago, Muon N' said:

Personally, the ones I have heard that I liked are all NOS and ones like Mullard, Philips, Amperex (bugle boys) ect'.

 

I have a small collection of Mullards (ECC83 and ECC81s) that sound OK.     

 

Years ago I had a bunch of Bugle Boy and Telefunken pulls that tested great.   I compared them to the Aussie AWV and Philips miniwatt, and thought that maybe they were a bit better, maybe not. Anyway, the prices they were getting on eBay were astronomic, so I sold them off.  I figured others like them way more than I did, or rather than I liked the money

 

I am still using the AWV 12AU7s.

[Ittaku]

I listen to my system a LOT. Every NOS tube I've ever put in has gotten noisy or failed before its time. As a result, I've given up on NOS tubes and just try to find the best modern production ones. YMMV.

[aussievintage]

33 minutes ago, Ittaku said:

I listen to my system a LOT. Every NOS tube I've ever put in has gotten noisy or failed before its time. As a result, I've given up on NOS tubes and just try to find the best modern production ones. YMMV.

 

It's the luck of the draw.  I have about 5 electro-harmonix.  Two of them have become noisy.  One seems to make funny noises as it warms up.  Not a great recommendation for new tubes.  I used to say I like them - and I did, the sound is good.   However, the relationship has soured.

[aussievintage]

35 minutes ago, Ittaku said:

I listen to my system a LOT.

 

Oh and yes so do I.    4 to 5 hours a day is normal when I am home.  Today, the stereo has only stopped for about 1 hour since I got up.        I do go away for months at a time as well though  

[Be Quiet...Listen]

NOS tubes are head and shoulders better than the current production offerings. But, in saying that, I do feel that the current companies are improving. Ever so slowly

I have been slowly collecting a little bag of older tubes and listening to the differences between the Euro, English, Japanese & US tubes. They all have either strength and weaknesses and it’s very hard to recommend a tube with knowing 1) your complete system. 2) what music you listen to and 3) having an idea of how you ultimately like to hear your music.