New 12AX7s from Audio Research

I'm wondering does anyone know the measured specs of what ARC considers a low noise tube suitable for use in the phono section (only 1 needed for the sp16 apparently)?

How about the other 5?

I am thinking it would be good to know these tube specs as a means of being able to shop multiple sources for similar performing tubes.

I gotta say, the new tubes do sound fantastic! They were expensive but so far seemingly worth it, I suppose.

Very open, dynamic, lively and vibrant on both the Dynaudios and OHMS with both digital and phono. Who ha! Good stuff!

Like a bright shiny new red Porsche glistening in the sun, or something like that!

Have not listened to the Triangles yet, but expecting good things there as well.

Yup v4 is the right rear slot of the preamp. If you look close at the board the numbers should be printed next to the slots.

Barruch,

WIthout the manual in front of me, v4 is the right rear slot (phono tubes on right, LS on left), correct?

That is where I put my primo tube to get good results but this was a guess/trial and error process for me since no directions regarding the primo tube was provided.

The $55 dollar tube is the low noise tube and should go in v4 in the sp16 for a quiter phono stage. I just received these west germany tubes too and they sound great, very transparent. The sp16 sounds warmer to me with these tubes. They are worth the money and should last 3 to 4 thousand hours, to me thats 4 to 5 years depending on listening habits.

ARCs website says they avoid NOS for various reasons.

The rep I dealt with (Calvin) indicated a new West German supplier, that's all. I did not question further in that they know a lot more about tubes than I do.

They were actually out of 12AX7s when I first called and in process of onboarding tubes from the new supplier. My tubes shipped about two weeks later.

5 tubes cost $40 and one $55, which I did not expect. The $55 tube apparently measured better in some way. I did not receive install instructions , but found a placement combo with the more expensive tube in the phono stage that resulted in low noise levels similar to what I recall when the unit was new.

ARC warrants their tubes for 90 days under the basis that most issues with new tubes will make themselves known sooner rather than later.

I am satisfied, but $250+ to retube a pre-amp ain't pocket change. THe thing does sound really good though!

That could CONNOTE, "manufactured by Siemens."

Are these ARC tubes "new production" or NOS, (new, old stock?). I wasn't aware of any new production tubes coming out of West Germany? Maybe there is a new plant there.

If they are NOS, could be Telefunken, Siemens or Amperex.

Glad they sound good and you like them.

The new 12ax7 tubes from ARC are in and sounding good.

ARCs new 12ax7 tubes are "West German".

Does that infer Telefunken or could they be from some other W. German maker?

For about that kind of money, you can buy the new Psvane 12AX7 Grade A, fully matched from Grant Fidelity. I have some of these in one of my phono stages and LOVE them. I think there is someone here on the 'Gon that sells them also. I have only purchased from Grant Fidelity...excellent company.

I would get matched tubes from Vintage Tubes in Michigan, Great prices and service! I have used him to retube both a Ref 3 pre and Aesthetix Atlas amp with better than factory results. AR checks closely for matched output but you can get a better suited for you sound with a quick conversation and still have matched tubes, often cheaper. Cheers

$40.00 per 12ax7 is an outrageous price for that type tube. Get a nos GE or Sylvania for about $10.00 a pop and you will be very satisfied with them.