[davidrs]

I have an Ayon Spirit II integrated amp.

The Ayon distributor is recommending NOS RCA 12AU7s with 62-19 markings, that were made in 1962. I have been informed that there are no additional markings on the tubes.

I do not have any photos and I came up empty with my online searches.

Curious if any members have any thoughts regarding, or experience with, these particular tubes.

[troutboy]

The best sounding RCA 12au7's i have come across are clear top 12au7's.  Interesting that he recommended a tube manufactured in a specific week in 1962 for the unit.  I would think that some of the earlier 1950's tubes would probably perform as well or better from my experiences with the clear tops.  I actually do have some 1962 RCA cleartops but i didn't check closely enough to see if they were manufactured in the 19th week though.

[HAITIMAN]

I have an Ayon Spirit II integrated amp.

The Ayon distributor is recommending NOS RCA 12AU7s with 62-19 markings, that were made in 1962. I have been informed that there are no additional markings on the tubes.

I do not have any photos and I came up empty with my online searches.

Curious if any members have any thoughts regarding, or experience with, these particular tubes.

Easy. Just ask the Ayon guy..."are these RCA "cleartops?" The answer will be either, "yes" or "no". If the answer is yes, then give them a try. I have them in my Rogue Cronus Magnum, (the Ultravalve Destroyer), and I am very pleased with the result. Mine are branded CONN....as in Conn Organ, so they were manufactured for use in Conn organs during the '60s. If the answer is no, then you are likely going to get RCA grey plates. I don't have any experience with these.

[davidrs]

troutboy and HAITIMAN,

Thanks. I will follow-up with them and check whether they are clear tops or not as well ask a few more pertinent questions.

Ayon USA did say they tested and listened to the Ayon integrated amps with 1950s RCAs, and that these specific RCAs came out on top for the preamp section.

I found it interesting that Ayon Austria allows the US distributor to make the final call on which signal tubes to use. My amp came with Raytheons.  Ayon Austria does hold fast on the output tubes, though.

 

[WGH]

I don't know about those particular tubes but Jim McShane knows tubes and is a straight shooter.
http://pages.prodigy.net/jimmcshane/tubes.htm

From his web site:

(1 matched pair) 12AU7A RCA clear top, used but test new and look good! This pair is Gm & gain
matched and has near perfect section balance. $44.50/pair.

[davidrs]

(1 matched pair) 12AU7A RCA clear top, used but test new and look good! This pair is Gm & gain
matched and has near perfect section balance. $44.50/pair.

WGH, Thanks. I will add these to the short list.

[davidrs]

I have additional information on these tubes.

They are not Clear Tops. They are 'Black' Getters described as lighter than black - so I'm guessing grey, as pointed out in the responses, and described as a 'step' down from the clear tops (also confirmed by the rep).

There is a "round halo" between the getter and top of the tube. This was described as being better than RCAs with rectangular or squarish halos. (If someone could explain what this means and whether it is relevant, that would be very helpful).

Finally, the tubes are Brand New NOS (never used). Advantages or disadvantages with this?

According to their tube techs and matching with the amp, they feel the ones I'm inquiring about offer the best balance of performance and value.

I have not made a decision as of yet. Based on other threads, the Psvane Black Treasures are also on the list.

Thoughts? Thanks in advance for your help.

- David.

[ltr317]

I have additional information on these tubes.

They are not Clear Tops. They are 'Black' Getters described as lighter than black - so I'm guessing grey, as pointed out in the responses, and described as a 'step' down from the clear tops (also confirmed by the rep).

There is a "round halo" between the getter and top of the tube. This was described as being better than RCAs with rectangular or squarish halos. (If someone could explain what this means and whether it is relevant, that would be very helpful).

Finally, the tubes are Brand New NOS (never used). Advantages or disadvantages with this?

According to their tube techs and matching with the amp, they feel the ones I'm inquiring about offer the best balance of performance and value.

I have not made a decision as of yet. Based on other threads, the Psvane Black Treasures are also on the list.

Thoughts? Thanks in advance for your help.

- David.

David,

The "black" is not the getter, but the plate color.  It's actually close to a charcoal grey, hence blackish is more correct.  The getter is actually the halo ring, or square, horseshoe, disc or other shape of the top metal piece as it protrudes from the rod.  Back when they were manufactured, they cost the same as any other 12AU7 and not considered special.   I've had several of the RCA charcoal grey 12AU7s, as well as other brand charcoal grey tubes which I have sold.  In some circuits, they sound very nice.  I guess the Ayon folks like the tube in their circuit as well. 

Paul

[HAITIMAN]

You gotta' buy 'em and try 'em. Nobody can tell you exactly how any tube will sound in your system.
Do a little research and buy a few variants, ie. Mullard, Telefunken, Raytheon, GE, etc.

I finally settled on 2 RCA cleartop 12AU7s and a Tele smooth plate for the gain stage, and then 2 Tungsram 12AX7s (labeled RCA!!) in my amp. Plus I have a complete set of Mullards that I haven't even tested yet. Not cheap, but you have to pony up the bucks if you want to get started with tube rolling. Most anything you try will be an improvement over current Chinese or Russian tubes. Don't be afraid to try used tubes that test well. These small signal tubes have a long life. My Tele is used and it is a sweet tube indeed. Worth every penny.

[davidrs]

Paul (ltr317),

Thanks for the explanations. Very helpful.

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"You gotta' buy 'em and try 'em." C'est bon!  I'm getting there, Haitiman!

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[Starchild]

I too have rolled many a tube over the last 13 years.  However, I couldn't accurately hear the tube's true characteristics until I started using Herbie's tube dampers a few months ago.  Whatever tube you use, you won't hear them at their best until you try the dampers.  I'm using two Radiotechique and two RCA black plate 12au7s with a Bugle Boy 6es8 in my Margules preamp and I love that combination.  Very open, great soundstage and good dynamic bass.

Mike

[davidrs]

I too have rolled many a tube over the last 13 years.  However, I couldn't accurately hear the tube's true characteristics until I started using Herbie's tube dampers a few months ago.  Whatever tube you use, you won't hear them at their best until you try the dampers.  I'm using two Radiotechique and two RCA black plate 12au7s with a Bugle Boy 6es8 in my Margules preamp and I love that combination.  Very open, great soundstage and good dynamic bass.

Mike

Mike,

I'm using Herbie's Tube Dampers. +1, in a major way, on your statement regarding Herbie's Dampers.

Advantage of mixing the Radiotechnique with RCA 12AU7s vs. going all of one or the other?

- David.

[bpape]

Which you get depends on what you want.  There is a LOT of difference between 12AU7 RCA blackplates and 12AU7 RCA clear tops.  Clears will bring things forward with more detail and are good if your system is too laid back.  Blackplates will mellow things out, bring up the bottom and smooth the mids but without killing the extreme high end.

All depends on what your system needs.

Bryan