Audio Aero Capitole - 6021W subminiature tube ??

I would appreciate hearing from someone who can explain the performance of these tubes in the Capitole, including the typical life of the tubes, whether they are susceptible to becomming microphonic or noisy, and how to purchase or change them if necessary. I believe I read these are really small (like the diameter of a pencil) and that they are soldered onto the board. If that is true, is it then necessary to send the player back to the distributor or manufacturer if they need replaced, or are these readily available and set up for user installation? How many years is typical for the tubes to perform in the Capitole before replacement is necessary? Thanks.
They will last and perform well about 10 000 hours (said manual). Ask details from Audio Aero. I had capitole (4 years)and Prestige (3 years).
Why don't you contact the US/Canadian distributor of Audio Aero, Globe Audio Marketing. I'm sure they can answer any questions you have regarding Audio Aero products.
I have the 24/192 and it sounds so great that I don't even worry about any of that. I've read that some have replaced the tubes themselves and others have had theirs replaced quickly.

I was running through transport's and dac's before this player and now I've been content for at least six months. Just buy it. Your cd's will sound far better then anything under $3500.

The only exception is that well recorded hdcd's still have a slight advantage on my Arcam 23T. Slight.
Thanks everyone, you provided the information I needed. I chose not to contact Globe with this question, because if I purchase one of these, it will probably be used so I didn't want to waste their time.
Mitch - I own the Capitol 24/192 with a "modified" SE mod (cryoed tubes & upgraded caps). The folks @ Globe are quite helpful and responsive... don't hesitate to get their input, as they are the best to contact if you are needing advice or repair work. This CDP is a keeper... highly recommended!
I watched 'Globe Audio' change the tubes on my MKI a few years back.Even I was nervous just watching.
Not recommended that you try changing yourself.They are soldered in and you can fry the board in a second and then the tears.
Again, thanks for the responses. I own the Lector MkII and will soon have the MKIII board installed. I suspect it will retain the same sound with a bit more resolution. I have considered trying the Capitole primarily on the strength of all the positive owner comments, but as I do more research I wonder if that would be a lateral move from the Lector. I was curious about the Capitole tubes because it seems they must last a long time, which is a good thing for someone who doesn't particularly like dealing with tubes, but of course no tube rolling. I recently installed a pair of special NOS RCA triple mica 12AT7's in the Lector, and they are a noticable improvement over the stock tubes, which are also good to begin with. I don't particularly like dealing with tubes so what I would really like is an excellent solid state redbook player that does the same soundstaging and organic midrange thing as the Lector. I just don't know where to start looking at a reachable $3K or so price range.
Its not that difficult to solder in a pencil type tube with flying leads. You clip the leads of the existing tube near the glass. Then grab the lead with a tweaser, apply heat to the circuit board connection and remove each cut lead. Then just solder in the new tube.
I have owned the Capitole Mark ll and now the Prestige Reference with the cryoed tubes. The new cryoed tubes are expected to last up to 15000 hours or more even though the book still says 10000. Since these are run at a tricle the new cryoed could go way beyond even this. When I had my capitole and replaced the tubes with the new cryoed set (big change) I simply found an experienced audio repair technician in my area to replace mine that had a soldering station. With the unit delivered to them you simply retard any risk of shipping damage. It is really no big deal and Aero designed it this way to keep noise from the signal path developed by tube sockets.
I have had stock 6021Ws go out after three months in 3 differnt Prima CD players. In fairness, one channel or the other not both. Since the player mutes in "stop" position, you have to start a disc and then pause it to hear the noise.

The distributor is very hard to get a response from, even through a reputable dealer and the experience has really damped the otherwise nice sound this player produces. Clearly Audio Aero has purchased a bad batch of these but has yet to rectify the problem.

I have currently been waiting over three weeks for a response on my latest 6021 problem.
Having owned (currently still do sort of) a Capitole, I recently sent it to Arizona for new tubes to be installed - a fairly easy process and not too expensive. The company is Sedonix and are the official service center in USA for AA.

Unfortunately my CDP came back via UPS and no longer works - thanks again UPS.

Plan to replace the tubes every 3-5 years. You should be able to have a local service shop do as long as they have very good soldering skills.
If you leave the unit on all the time, like I do with my Prima mk2, those tubes won't last more than 2 years. I just replaced my Prima's myself last month after 17,000 hours and the improvement that new tubes brought was shocking. So I suggest you do it at least that often if left on 24/7.

The manual says do it every 10,000 hours but normally 6021 tubes last much longer. They were designed for circuits subjected to exteme g forces, such as missile guidance systems, and to have likewise extreme reliability. I have read that some can last 100,000 hours. But it seems AA makes them run very hard because my old tubes had obvious signs of space charge degradation (leaves a sooty film on the inside). So 17,000 hours was too much already IMO. It may be worse in the Capitole, not sure.

Also, the Sylvanias are not made the same as the Philips. Perhaps part of my improvement was due to the change in brands. The stock Philips have gray open plates whereas the Sylvanias have boxed black plates. So the are NOT the same construction which means they could well sound different. This has been my general experience with tubes in any case.

Replacing these tubes is easy if you are a patient person and have access to a high-quality soldering iron. Having the right tool is everything so don't attempt this with a Radio Shack special. Let me know if you want detailed directions.

Hmmmmm...My Capitole's tubes are more than four years old. No problem yet.

Good Thread.
Oh, there was no problem with mine either - I got used to the gradual sound degradation! It wasn't until I installed new tubes that I realized there was a problem before. Besides, I didn't want to wait until an obvious issue "popped" up. You never know how much damage a shorted tube can make and I don't like waiting to find out! For $20 and 1 hour of my time, I am off to a fresh start - and my Prima sure sounds like it too.

how much is it for a pair of 6021 tubes. do the SE upgrade really need cryo tubes. or changing capacitors make major difference. V caps are only $100.

comments please

Thank you in advance
AA Capiyol reference - SE upgrade

i got V caps directly from their web site for $100.


1 pair of 6021W cryu' from another site for $75

looking for that vibration pads. Any idea whwrw to buy that from ?
Hi masilu
Are you happy with your upgrade. What sort of difference did it make to the sound? Thanks
Hello everybody,
Since it is capitole thread maybe somebody had similar problem.
When my monoblocks (Clayton M100) are connected to my CDP Audio Aero Capitole mkII with XLR interconnect, there is pretty audible white noise. When I disconnect XLR connection noise disappears. Noise have constant level in both channels. When Claytons are connected to CDP with RCA interconnect there is no noise, dead quiet.
Any idea why ? Any suggestion. Is not supposed XLR to be quieter connection ? I have tried many different RCA, XLR cables, always the some, so problem is not in a particular cables make, but in the connection itself. problem must be either with AA Cap or with Clayton.
Sorlowski- Have you checked to see that the pin-out on the balanced output on the AA is the same as the pin-in on the Claytons? There are some products out there with a non-standard configuration for the XLR connectors.
That is an interesting thought. Is it not normalized, especially that both Clayton and AA cap are products designed for US market. US How do I check that ?
How do I check that ?
If you have a multimeter, check for continuity between xlr pin 1 and the ground sleeve of an rca connector. Otherwise check with the manufacturers.

However, the most common inconsistency in xlr pinouts is that the signals on pins 2 and 3 are interchanged, which would not affect hiss levels. It would just invert polarity, sometimes referred to as "absolute phase," which would have minor or negligible effects on many or most recordings.

Also, check that continuity does NOT exist between pin 2 and ground, and between pin 3 and ground. A near zero resistance between one of those pins and ground would indicate that the unit does not drive the xlr connector with a differential pair of signals. I would be very surprised if that were the case, but if it were it would go a long way toward explaining the hiss.

-- Al
I suspect that the polarity and pin set-up between the two is NOT the issue. Do a search on invert in the preamp/amp section and you will see from some pretty knowledgeable people (amp designers, etc. . .) that such an issue is not going to cause this problem.

I think you can immediately narrow down the problem to one of three causes:

1: the least likely cause is that you balanced cables are defective. Use, borrow or buy (even a cheap one at a local musical instrument store) and try the new one and see if the noise goes away.
2: there is an issue with the power amps' balanced input handling of that signal internally in the amp (this can easily be tested by an RCA to XLR plug, running the RCA from your Capitole to the balanced in of your amp to see if you are still getting the white noise).
3: there is an issue with the balanced outputs of the Capitole (you can determine this by buying or borrowing an adapter so you run the XLR balanced cable out from the Capitole into the single ended inputs on the amp and to see if you still have the white noise). I suspect this is going to be your problem. Why? Because the Capitole CD players are known for failing or breaking down. They are musically great sounding, but they are made in France!
I have done tests with multimeter, happens that I have Fluke, so I could get pretty exact measurements.

>check for continuity between xlr pin 1 and the ground sleeve of an rca connector

there is continuity 0.14ohm which is 0 for my Fluke.

AA Cap
RCA - 0,52 ohm
XLR - pin 1,2 0,45ohm
XLR - pin 1,3 0,57ohm
XLR - pin 2,3 0,83ohm

I was surprised how low output resistance of this CDP is.

RCA - infinity
XLR - pin 1,2 0,85ohm
XLR - pin 1,3 infinity
XLR - pin 2,3 infinity

So it seems like Clayton is not a balanced amp, he is is the culprit, am I right ?
Wow! Those are indeed strange readings. Let me first verify a couple of things, which I hope you won't mind my asking:

1)Did you make these measurements with power off, which is how they should be measured? If power was on, voltages such as dc offset, ac leakage, etc., might have confused the meter.

2)When you say "0,45ohm," "0,57ohm," etc., am I correct in assuming that you mean "0.45 ohms," "0.57 ohms" etc? And are you sure that the scale the meter was set to was ohms, not Kohms?

Assuming those answers are "yes," I too am very surprised at the low readings on the cdp outputs. However, the 0.14 ohm reading from xlr pin 1 to ground appears to confirm that pin 1 is ground, as it should be.

Did you also measure from xlr pin 1 on the Clayton to its ground (the shell of an rca connector, or chassis)? Looking at your readings, I'm wondering if perhaps for some strange reason pin 3 is used as ground on its xlr connector, instead of pin 1.

Best regards,
-- Al
1) Yes I did measurements with power off.
2) Yes I meant 0.45ohm

I did some additional measurements:
XLR Pin 1, ground (on chassis) 0.28ohm
XLR Pin 2, ground (on chassis) 0.9ohm
XLR Pin 3, ground (on chassis) 22Mohm and falling

XLR Pin 1, RCA ground 0.18ohm
XLR Pin 2, RCA ground 0.8ohm
XLR Pin 3, RCA ground 32Mohm constant

Thank you for your interest.
OK. Perhaps the very low numbers looking into the Capitole's outputs indicate that its outputs are transformer coupled. If that is the case, dc resistance measurements probably don't tell us very much.

Based on the additional measurements, I agree with you that the Clayton's xlr inputs appear to be unbalanced. It looks like pins 1 and 2 are both grounded, and the only input used for signal is pin 3, perhaps through a capacitor.

Since the xlr interface therefore appears to be essentially an unbalanced interface, it might be worthwhile temporarily isolating the amp's ac safety ground, via a cheater plug. Perhaps a ground loop, to which unbalanced interfaces are susceptible, is causing the noise (although a ground-loop problem would usually involve low frequency hum, as well as high frequency buzz, and I'm not sure why the rca output would be quiet if a ground loop were the problem).

Also, I'm wondering if the Capitole's output circuit may be having problems due to having the signal it outputs onto pin 2 shorted to ground, by the Clayton. If possible, it might be worthwhile trying a specially prepared xlr cable that leaves pin 2 unconnected.

Just some thoughts.

Best regards,
-- Al
So I went in quest for XLR to RCA adapter.
I have found one gold plated which I liked.
But it got PIN3 disconnected and PIN2 connected to center pin of RCA plug.

But looking at my measurement I need one with PIN 2 disconnected and PIN3 connected to center pin of RCA plug.

So appear that XLR wiring is not universal or my Clayton’s quasi-balanced XLR inputs are wired wrong way ?

Or they are two schools of wiring quasi balanced input in power apms?
Usually USA-made equipment uses xlr pin 2 for the positive polarity signal, and pin 3 for the inverted polarity signal. The opposite is done in equipment made in some European and other countries.

Therefore rca-to-xlr adapters that are available in the USA usually connect the rca center pin to pin 2 of the xlr connector.

If the Clayton is indeed designed to use only one of the two differential signals, perhaps it uses pin 3 instead of pin 2 to compensate for a polarity inversion in its internal signal path. Or perhaps its input circuit is somehow defective, or miswired. All I can suggest is trying to contact someone at Clayton, or one of their reps or dealers.

-- Al
After all hassle appeared that Clayton's have been OK. And AA Cap finally died on me. There is no sound anymore, only quiet hum is coming out of both speakers. So I'm going to take advantage of my misfortune and upgrade it. I'm planning to replace Hovland Musicap with VCap CuTF caps, and Philips Jan 6021W with Sylvania . I have heard that Sylvania's are the best 6021W ? Is it much difference between plain Sylvania's and cryoed Sylvania ? Where can I buy cryoed Sylvania's, I'm having not luck finding them.
About my recent modification:
I have changed Musicaps in my AA Cap to VCap CuTF ($202). After 500 hours of burn in I have started my audition. I hoped that there would be any difference, to my surprise I have got real increase in transparent and resolution. But under the stipulation that AA was powered from AudioMagic Elipse. When powered directly from mains, differences are negligible. Now music is much more involving. Best upgrade I have done recently.
I was so excited about my "reasonably cheap" upgrade success, I decided to upgraded my Jan Philips 6021W stock tubes to cryo Sylvania 6021W.
Another 500 hours of burn in, and I have started my audition, no change in resolution, transparency, but I have lost bass impact and dynamics, I'm really frustrated.

How this could have happened, are not Sylvania's supposed to be better ?
Maybe Sylvania simply do not work well with VCap's ?
Did anybody tried Sylvania's in AA vs Philips ?
What were the results ?
I do not know what to do, pay technician to resoldier my old Philips, or maybe process of soldering tubes charged electrostatically AA board and I have to wait longer for it to discharge ...
You said in a previous post your AA Cap had died, what was wrong with it? Congratulations on the upgraded caps, where did you have the work done? Where did you get the cryo Sylvanias? I found several Sylvanias and I was going to get them cryod but I'm not sure it's worth the trouble. I think it was more of a way to sell an upgrade to reference.

Thanks in advance for any info you can give,
What was wrong, good question... nobody knows.
After months of fruitless repairs, appeared that he did not like my Legrand Power Strip to which my Audio Magic Eclipse was connected, AA was connected to Eclipse. I had to connect Eclipse to power strip which do not have any reactive elements, just the cheapest, simplest one I could buy. My AA is very finicky when it comes to power supply. It works from one socket at home and do not from another. I know it sounds crazy. I have asked electronics engineer about that, he was flabbergasted and could not explain it seeing it by himself.
Important now it works.

I get Sylvania's in Finland: Have sent them for cryo treatment to: (really cheap).

Do you know if in SE upgrade Philips or Sylvania 6021 W are used ?
I have the AA Cap Reference SE and my tubes are Philips, this does not mean the Philips sound better than the Sylvania, I think the Sylvania are just in short supply. I got some Sylvanias from Vacuum-Shop and another source from that part of the world. I contacted Tube World about getting mine Cryo treated but I'm just not sure it's worth it, Like I said, I think the Cryo might have been part of the selling point of the SE upgrade.
Soldering 6021wa tubes into the circuit.
Audio aero tubes are soldered in with short leads and
the tubes in vertical position.
this may lead to some microphonics problems.
personally i keep the leeds lonng and bent the wires so the tube are iin an horizontal position more or less floating position.
I can give you some tubes for trial.
good luck
AJ van Doorn

i created the "SE"upgrade for initially the North American distributor: Globe Audio Distributors, then it was installed at the factory after most existing pre "SE" capitole, prestige and prima dac were upgraded in the field ,most in Canada at Globe and also at the tech in Arizona. The caps in the kit were Sonicap platinums, a silver composite/teflon film and foil cap. Careful listening experiments revealed unanimous overall improvement over the rel cap tft. Lesson # 1, all caps that are film and foil teflon do not sound the same. V caps performance according to 1 high profile boutique tube manufacturer were similar quality improvement over hovland musicap but different than the sonicap platinums. Sonicraft does not have any more of this value of cap. I have a dozen pair or so in storage,as well as the damping/mounting pads. We tried many nos 6021w but went back to the phillips jan and cryoed them,most upgraded and earl factory "se"will have these tubes except some of the early units that were upgraded in the field. Never did as careful, controlled listening tests on different tubes, consistency and supply being in favor of the jan philipps . Cryo tubes  make a difference if you have a well sorted system with excellent cables(and yes good cryoed cables allow you to hear the difference more easily cryoed tubes make). It does the same thing ;sounds more resolved and refined, quieter, more relaxed,more involving 3d halograph sound. Cryoing tubes is not cheap so if was not worth the expenditure, we would not have done it. Everything in that "se"upgrade kit, made a difference. Also all caps were matched as well as tubes were tested/matched after cryo for symmetrical gain/noise /microphony. I produced the kits along with a well known high end audio tech/designer. Globe Audio distributed to their dealers and the initial factory production of "se". Did have some good results ourselves with sylvania gold 6021w and the few close friends with them. I think a Mark 1 Capitole has the same sylvania golds 15 years now, i'll check on that next time in Canada.



Very interesting as well as re-establishing an old AA thread. Is Globe Audio or Sedonix AZ still operational? If operational, does either business still support Audio Aero players?


Happy Listening!

Globe Audio is long gone. But Sedonix might be operational. I got a used Prima 2 dac last year( from Jody, former Globe owner)waiting for me in Canada.

I plan to install Dueland cast caps. Rich at Signature sound mentioned that he tried some Dueland RS i think in a Capitole and liked the improvement over the se caps.

In the last 10 years or so i've been mainly listening ,experimenting with NOS dacs using philips 1541, 1543, 1545. I felt that although upsampling dacs like AA Prima/Capitole have some interesting qualities, they seem to add some amusical noise in the high frequencies. Probably delta sigma dac noise shaping anomalies.

Also going to compare a Berkeley Alpha dac with hdcd. Should be interesting comparing these 5 dacs.



Excellent! Thank You for the follow up. Someday, I would not mind seeing Audio Aero establishing a come back. A revamp of the brand.


Happy Listening!