speaker hiss with audio aero capitole mkII

I have noticed a hiss from my egglestonworks andraII speakers that is noticeable from the listening position at the highest volume settings on the audio aero capitole mkII. The hissing comes from both the tweeter and the twin mid-range drivers from both speakers and is equal from both sp's. It gradually increases as the volume is turned up and is not present with the capitole turned off and the Krell fpb 300cx on. I have dedicated circuits with their own main panel and the capitole is connected to a PS audio P-300. The hiss is present also when the capitole is not connected to the P-300. I suspect that this relates to intrinsic noise or distortion in the capitole, possibly from the tubed analog output. Although the system sounds terrific, i am concerned that the hissing may be masking low level detail at moderate to high listening volumes. Has anybody had a similar experience with the capitole? Can this be improved? Any suggestions? Thanks.

Rafael, I audition Krell 300 KPB and when I read the
brochure of krell, I think if you use tube, you
iether the amp or your cd if you use it direct,
Read the Krell instruction.
Sounds like tube hiss to me, eithew because you need quieter tubes, or you need new tubes, or the noise is inherent in the design. I have the same problem with a CDP, but the hiss is low enuf in level that it doesn't obscure any musical sounds at normal listening level.
Sorry about my post I didnt proof read it, You can
damage, I think the Krell amp or the tube preamp.
Read the instruction of Krell.Iam not sure if your
are using cd direct.
I was aware of the problem with the krell and tubes that requires engaging the coupling capacitors on the krell to be compatible with tubed inputs. However, because the capitole has a subminiature tube in the output i didn't think much of it. I may be wrong and i just e-mailed krell about it. I will post the answer from krell. Thanks for the advice and for waking me up to this potential incompatibility! Yes, i am using the capitole direct to the amp.


With regards to the Wadia, if i change the audio aero i'll
be going to the Meitner DCC2. But thanks for the advice.

My AA Mark II is perfectly quiet when run through my McIntosh Tebe receiver and when run through my other tubed amps. Hve tried running the AA through another amp?

If you have a really good rapport with your local high end audio shop, try bringing the AA down to them and try it on a couple of amps. Just remember, there is a skrew holding the transport in place that is meant to snap if the AA Mark II is bumped during, say, shipment. The problem is easy to repair, but might be a bummer of a new problem.
How old is the CD player? I think you can tell by the first four numbers in the serial number (0207/335 would mean July of 2002) The little tubes in the A.A. are supposed to be good for at least 10,000 hours (14 months of being on standby or in use) and that's probably a conservative estimate. The tubes would probably go bad one at at time, but I suppose both tubes could be well past their "freshness date" if the player is a couple of years old.
The player is usually very quiet.
the Capital will exhibit the "pin #1 problem" with some amps with balanced cables only due to grounding issues between the components
Golden ears,

The serial# is 0207/338. I can't tell the # of hrs. on the tubes 'cause i bought it from the original owner. He told me that he had put ~600 on it when i purchased it, but this may be an underestimate. Also he may have not counted stand-by time. In any case, the music is played beautifully by the capitole is just that with the music off and the volume setting at the highest levels a hissing sound is heard, not a hum. Would that be how a "bad" tube present? I really am not that experienced with tubes.


How can i tell if i have a "pin #1 problem"?


Are you saying that you only hear the hiss when you rotate the volume know to maximum? If so, I wouldn't worry at all. There are a lot of tubes that have a low level residual hiss - if you can hear it at normal volumes you would either have tubes that were noisy in the first place or tubes that have gone noisy after some use. Neither of these things are unusual and present no electrical problem (but be wary if you're hearing snap, crackle and pop sounds after warm up - this would indicate that you should probably replace the tubes).
Yep, you guys are right . This does not affect the sound quality at normal or reasonable listening volumes and is only noticeable at the highest volume setting into the very powerfull Krell amp which obviously at that volume level is greatly amplified. There are no crackles, snaps or other noises. Krell's answer, in true manufacturer's fashion, was that they weren't familiar with the AA capitole or its tubes, right! I am satisfied, however, that this is not of significance and had a great listening session last night at the volume settings i like! Thanks to all for the great advice!

So, we have here yet another AA Mark II beliver. Yes, the thing can be tempermental, but we do love it!
Same thing happens with my Cap MkII. The curious thing is that the hiss is mainly heard in the right speakerĀ“s treble and mids, while in the left I only notice it in the mids. I run Stereophile's phase test and the pink noise clearly sparkled in the same place as the hiss (right speaker mid and treble). Another thing I notice is very strons sibillants (harsh s). My speakers are Von Schweikert VR4.
Have you reversed your speaker connections st see if the problem moves with the change. Then, try it again with your other connections. If the problem changes "downstream" it might not be the Cd player.
It is clearly from the Capitole. I connected my other player (Rega Jupiter+IO DAC) and it is dead quiet. I even turned the volume down on the Capitole to -7db to match it with the Rega's 2v output and the hiss persisted.
One more suggestion. Try reversing the connections at the Capitole. See if the hiss follows. Also, do you have XLR connections? Trying a different output (XLR) might tell you if this problem is just in the terminal, or a least somewhere past the DAC. When you have tried all of the above, call Globe Audio. They are very helpful. I don't have globe's phone number handy; it is an '800' number. You can find it by doing a search for 'Globe Audio'.

I do suggest all possible tests before calling. The more you can tell them, the better the help.

Good Luck!
How old is the player? There are two 6021w subminiature tubes inside. If the player is more than about 18 months to two years old, those tubes may need replacing. They would not grow old at the same time (if you know what I mean) or in the exact same way, so you'd start to hear a little noise in one channel, then the other a little later....?
Interesting thought. Perhaps reversing the tubes will answer the question. Also, it could be possible--although a remote one--that one of the tubes just needs to be tightened.