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12ax7 upgrade recommendations

I

IanTY

New Member
Hi, I've just ordered a Pro-Ject Tube Box II phono pre-amp. I am thinking to the future for possible 12AX7 upgrades. Turntable is a Systemdek IIX with a Jelco arm and DL-103 cart. BTW, what are the "Pro-Ject" branded 12ax7's?

Can anyone recommend both new and NOS tubes for me to keep an eye out for that would be suitable for this phono pre-amp. Many thanks. - Ian.
 
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I haven 't gotten a straight answer from anyone... but my guess on the origin of the tubes in the Pro-Ject Tube Box is probably either EI or Tesla, or something similar. I'd expect them to source tubes locally to them... somewhere in eastern Europe...

Regards,
Gordon.
 
best thing to do is get a good cross-section of 'well-regarded' 12ax7's, roll 'em in circuit, and see which you like best . . .

telefunken, amperex, rca, GE, mullard . . . . everyone has their favorite flavor . . . there's also the 7025, which is a 'low noise' 12AX7 . . . might be worth checking out since it's a phono stage. I know at least the big US tube companies made them (RCA, Sylvania, GE). . .

sometimes you can find people selling mixed bags of 12ax7's on 'the Bay' for this express purpose.

I'll take vintage tubes over new production any day of the week :yes:
 
You can also try 5751s. Slightly less gain, but work well as a 12AX7 sub. With the possible exception of the generic GE gray plates (only mediocre), they sound very good.
Jack
 
As far as new production, you may want to try these:

Sovtek 12ax7LPS
TungSol 12ax7
Mullard Reissue 12ax7

I'd also recommend the Groove Tubes 12ax7M tube but there's been some decline in quality in the past year or so.

The above tubes are decent tubes and far cheaper than NOS. Worth a try IMO.

Jeff
 
If you never push your system (in terms of ultimate output volume) you might be able to try 12AU7s. You take a hit in gain, and therefor ultimate volume (5+ dB) for a given output setting. But old stock 12AU7s are often reasonably priced and most are dead quiet. Thats one reason why so many old tube organs settled on 12AU7s in their tone cabinets. On the flip side, many guitarists use older tube amps where 12AU7s and 12AX7s can be used interchangeably. But they avoid many of the 12AU7s because they can't get them to distort the way the 12AX7s will.
 
If you want great-sounding NOS, or strong used tubes, look for Mullards, from the Blackburn plant. The second line of the "date code" (a misnomer for Mullards) will begin with a "B"

Why a misnomer for "date code"? The so-called date code on an older Mullard tube tells you what type the tube is and which plant it was produced in, as well as the date. In other words, there's a lot more info there than which week of what year it was made. The Mullard date code tells you the month and the year, but not which week.

I'm using a pair of used, but strong testing Blackburn Mullards in the phono stage of my modified Counterpoint SA-1000 preamp, and the sound is stunning!
 
My JJ 12ax7s sound pretty darn good in my integrated's phono section. No issue after a few months of regular usage. NOS is better though I hear
 
IanTY said:
Hi, I've just ordered a Pro-Ject Tube Box II phono pre-amp. I am thinking to the future for possible 12AX7 upgrades. Turntable is a Systemdek IIX with a Jelco arm and DL-103 cart. BTW, what are the "Pro-Ject" branded 12ax7's?

Can anyone recommend both new and NOS tubes for me to keep an eye out for that would be suitable for this phono pre-amp. Many thanks. - Ian.
Click to expand...

Ian, I have a Tube Box II, although it's currently on standby because I've upgraded. It's a very good phono preamp and it got me really interested in tubes. It was also the first good phono preamp I owned, and I was thrilled at how much better everything sounded in my turntable system when I hooked it up.

The Pro-Ject branded tubes that it comes with are Electro Harmonix - I compared them and they're 100% identical in every way. While it will sound good out of the box, the EH tubes are hardly going to show you the best of what the Tube Box II has to offer.

When I began tube rolling I first tried Sovteks, which to me sounded like a real upgrade from the stock tubes. I then went through several new models of tubes and found the JJ Tesla to be without question the best-sounding in my system.

If you want the best you'll have to pay for NOS, which can be quite expensive. I wasn't thrilled with Telefunken 12AX7s (yes they are genuine) even though they're a very popular tube. Mullard worked quite well, as did Sylvania (a softer, warmer sound that brought out the midrange a bit, and less expensive than many NOS tubes), and GE 5751s like some recommended here - they're good with this preamp but there's less gain.

Unfortunately I have to tell you the very best were in fact the most expensive, many of which I bought from Upscale Audio, which has some amazing tubes, but you will pay big time because they're all rare, thoroughly tested and definitely never used. A pair of Holland-made Philips with dimple pan getters were amazing, especially in the higher frequencies, and there was improved resolution. The absolute best was the Pope 12AX7, which is apparently the exact same thing as the infamous and highly sought after Amperex Bugle Boy. When I bought them they were around $125 a pop, which is far more than most people can or would spend on tubes, but in every category they are phenomenal, and also the most neutral-sounding of any 12AX7 tube I've heard. I think the price has since increased because they're probably running low on these, and I think they're quite rare.

La Radiotechnique is a lesser-known French brand, so these are not always quite as expensive, but I highly recommend them. Very good imaging, solid all around.

I hope this helps a little. Remember that tubes are circuit and system dependent, so what I've told you might still not be your experience since we're only talking about the same circuit, and we have different systems.

I'd really like to hear your impressions once you get the Tube Box II, and of course once you start tube rolling.

Dave
 
jmathers said:
As far as new production, you may want to try these:

Sovtek 12ax7LPS
TungSol 12ax7
Mullard Reissue 12ax7

I'd also recommend the Groove Tubes 12ax7M tube but there's been some decline in quality in the past year or so.

The above tubes are decent tubes and far cheaper than NOS. Worth a try IMO.

Jeff
Click to expand...
This is the best list of new but Id put the Tung sol at the bottom of it as the Sovtek LPS is said to be the most dynamic of all 3 and haveing rolled all 3 latley in my little Bellari single tube along with an Ei silver long plate,I found my self removeing the tung sol,as it had a hell of a lot of gain,importaint in a single tube but not the most importaint it had big bass and trebble but weak mids,Not to bad because I'm am useing a Grado Gold and Ei pre amp tubes and Tad EL 84 driver tubes all midrange strong,the Ei's gave great highs and mids but lacked bass,the Mullerd gave me all three but laid there uninvolving luke warm boreing,the sovtek lps long plate spiral screen is fun and engaging bass ,mids and highs are all pretty even here and not microfonic like the Ei .
If money is no object 1950 to 1964 (west german) Telefunkens or Amprex Bugal boys(Holland made not France) or pre 1970's Mullards.
 
Awesome responses, many thanks to all for taking the time. Mr. Lin. I will indeed try to post my findings once I get it warmed through. It arrives Wednesday. Sorry I'm late responding to this post as I've spent all night assessing two Reel to Reel decks. One or the other will be used for spares. Akai 1722MKII and an Akai GX4000. Trying to make one good deck from the two. The 4000 is looking promising even though it has the higher milage of the two.

Once again many thanks. I'll re-read the post tomorrow to try to take it all in. - Ian.
 
IanTY,
Some pretty good 12ax7 suggestions have been given in this post. I would simply add the Raytheon black plates and the Sylvania black plates to the list of 12ax7s that you should try. The 1950s American black plates have a very rich and lush sound to them.
 
budget 12AX7s : the Shuguang 12AX7C9 is very warm sound, the Sovtek 12AX7LPS is very good too. Also be on the lookout for Matsushita and Toshiba 12AX7s - very well made and quiet too.

Through Ebay I've also bought Westinghouse tubes which are usually (but not always) relabeled RCAs. Also be on the lookout for Fisher/Dynaco/etc labeled tubes as these can often be Telefunkens, Mullards, or whatever.
 
Through my Eico HF 85 phono stage Tele smooth plates sound great with much detail; Mullard Gr. Britain old stock very warm and smooth; Amperex Bugle Boys the best so far with rich detailed involving instruments and vocals. The saxophone moved right in front of me where it felt I could bend over and look into that spout. Ben Webster never sounded so good. Hope that helps.
 
markus said:
best thing to do is get a good cross-section of 'well-regarded' 12ax7's, roll 'em in circuit, and see which you like best . . .

telefunken, amperex, rca, GE, mullard . . . . everyone has their favorite flavor . . . there's also the 7025, which is a 'low noise' 12AX7 . . . might be worth checking out since it's a phono stage. I know at least the big US tube companies made them (RCA, Sylvania, GE). . .

sometimes you can find people selling mixed bags of 12ax7's on 'the Bay' for this express purpose.

I'll take vintage tubes over new production any day of the week :yes:
Click to expand...


is there somewhere in particular one can go to read about these 'flavors'?
 
I just rolled some 1950 Standard Brand RCA 12AT7's short black plates into the pre stage of the Manley Stingray and WOW! are they dreamey.(NOS)
 
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