High Efficiency System- Noise Floor Reality Check?

Trying to gauge whether I'm expecting too much quiet with the system at steady state, ie idling, no music playing. System consists of Avantgarde Duos, with the latest version of the Audiopax 88 monos; Steelhead preamp running a single phonoplayer (The TT, arm, cartridge and wire to the preamp will change in about a week).
Everything is plugged into a pair of Shunyata Hydras- two separate units, one for the speaker/amp woofers (Hydra two, with two outlets; the other a Hydra 6, into which the Steelhead and Audiopax amps are plugged). Using fairly high grade Shunyata power cables on everything; the Hydras, in turn, are plugged into a Richard Gray Substation, a 240v step down transformer that has its own line.

What am I hearing?- well, if you put your ear up the tweeter or midrange horn, a soft 'zzzz' type electrical noise, and from the woofers, a muted 60 hz hum. From the listening distance you can't hear it at all. And, when you crank the gain up on the preamp, no music playing, these noises don't get any louder.
Am I hearing the invariable low level noise of electrical equipment through very efficient speakers? I'm not so anal as to believe I can eradicate all system noise on a set up of this type, but I'm concerned that even this low level of residual noise may interfere with the system's musical capabilities. Would love to hear from high efficiency types since this is my first horn based system.
I also have a good electrician who has helped me in the past, but I'm not sure there is anything he could do beyond this to improve the noise factor, is there? Reality check? TIA.
Having very efficient spkrs. & tube amps, you`re stuck with the residual noise in the electronics. I forget the name of the tune, but a line applies to your system, "nothing can be done."
Porziob........ Not so fast.

The 60 cycle hum should not be there. With my Duo's, Aesthetix, Art Audio (i.e. all tube system) all I hear when I put my ear next to the horn is a gentle tube hiss. I am not using any type of power conditioning in my system at all. I have a Shunyata Anaconda VX on my CD player, Cardas PC's on my subs, and an Argento PC on my preamp....... other than that all cords are stock. The thing I have done however is to run four dedicated 20amp lines, off of a dedicated breaker panel with it's own grounding etc.

I have the lines seperated for digital, analog front end, power amp, and subs.

I would try pluging your components into different lines if you can. You might try removing the powerstation, etc..... In short experiment until you get the lowest noise floor. If you can't get it to completely go away try your electrician buddy.

Chris has different electronics so you can't really compare. I agree with his advice to try various things to minimize the noise, but if you hear nothing at the listening position with these then you are in good shape. What matters is how it sounds at the listening position while playing music, not how it sounds with your ear up next to the speaker.
Well, you guys represent the extremes of the internal debate I have been wrestling with- it shouldn't bother me, but I don't like knowing it's there.
FWIW, I have already tried virtually every permutation I can within this room; I have yet another set of dedicated outlets that take from a leg of the 240 line that feeds the stepdown transformer, but this may still be affected by what's on that line, i guess.
As to the differences in electronics, no doubt you are right, Herman- the Audiopax amps are, as far as tube rush goes, quite quiet. But, there is that hum. Damn!
The only way to know for sure is to have another completely separate subpanel, with 20 amp lines set up and run into the room. So, I'm going to probably talk to my 'guy.'
Oh, and the sound at the listening position does keep improving. At first, I refused to invite the devil into the system by way of a CD player to break things in- so I was doing speaker break-in the long way, through playing and listening.
Then, I got impatient, so I hooked up a little portable and found my copy of Art Zoyd's 'Nosferatu,' a virtually unlistenable little sonice nightmare that is perfect for breaking stuff in. Let that run for a day or so;
still fiddling with speaker position and woofer settings, but the bass on a good recording is impressive and musical, if not real. (Again, went to a club last night down in the lower east side and listened to a couple bands- the kickdrum is impossible to duplicate, at least in my smallish listening area with this somewhat 'modest'system).
Thanks, all. :)
Whart, if you want to get the lowest hum possible from your system there is a simple device made by Granite Audio called the "Ground Zero" that may banish or seriously diminish the hum. I'd almost think it would be a must for a high-efficiency setup like yours. Here's a link to more info: http://www.graniteaudio.com/zero/index.html

The zzzz from the tweeters could be a differnt problem, possibly improperly shielded interconnects...

BTW, that's a great looking system you have there and I'd love to hear it sometime. I was very impressed by the Audiopax electronics when I heard them at T.H.E. Show in Vegas this year.

Have you tried cheater plugs........ Probably an obvious "Yes", but thought I'd ask.....

Just a point of reference regarding the Audiopax monoblocks and the Art Audio PX 25 amplifier. I've had both in my system driving Duos. Both are fantastic products. Although the 'Pax are quiet, the Art Audio PX 25 amp has a significantly lower noise floor. The Art Audio could be the quietest tube amp around.

Some people talk about a desire to achieve a noise-free "mystical" blackness where music appears against a noise-free background. Using the PX-25 with my Basis Debut 'table (w/its hydraulic suspension that keeps the 'table immune to outside vibration/noise) this blackness was achieved which adds significant enjoyment. Hearing low level details that would otherwise be missed, and to hear every note played during fade outs is a thing of beauty.

For high efficiency speakers such as Avantgardes, be sure to get the low voltage input option on the Art Audio PX 25.
"...if you put your ear up the tweeter or midrange horn, a soft 'zzzz' type electrical noise, and from the woofers, a muted 60 hz hum. From the listening distance you can't hear it at all...

I'm not so anal as to believe I can eradicate all system noise on a set up of this type, but I'm concerned that even this low level of residual noise may interfere with the system's musical capabilities."

My friend, listen to yourself. You're analyzing it to death.
You have the same problem as me, you are listening to the machinery and not the music.

I have found a simple solution; reading while listening. It distracts my analytical nature enough to allow my asethetic nature to enjoy the music without criticism. Try it.
Douglas, using your solution 'reading while listening', could also be applied to all perceived 'problems' with audio systems, especially those nasty sounding cables and PCs. Still, I don't know how you can listen AND read at the same time, if you are serious about any of the two!
Bob P.
'reading while listening' that'll make the music sound better

I like to listen while reading... it makes the book better too

Well, no joy yet. Got one of those Granite Ground Zero thingies, it does work, but it is not solving my problem (yet). In fairness to the manufacturer, I don't want to suggest that I have reached the end of all possibilities in using it- for example, where does one find a ground on the Shunyata Hydras? Those are the only 'components' in the system that have not yet been routed through the Ground Zero.

I also tried: removing everything plugged into the step down transformer other than the hi-fi system Shunyatas- no difference; running the Shunyatas into conventional outlets in the room that have nothing to do with the step-down transformer (and pulling the plug on the step down transformer as well). No dice.

My electrician came by yesterday- at first, he looked at me like I was insane for complaining about noise that you hear by putting your ear close to these big speakers- but, after a few minutes he acknowledged that he could hear it in the room, sitting nearby the speaker, not right on top of it.

He is of course willing to install a separate subpanel for 240, giving me the option of either leg to experiment with and setting up yet another group of dedicated lines with an isolated ground. This will involve some cost and some breaking of walls~ so i've been trying to find solutions short of that. The killer, though, would be for him to do all this work, and for me to still have the hum.

I suppose he could rig up something temporary to see if it does the job, but the distances are more than 50 ft. from the main panel to the room- and three floors up- I wonder if he has a really long extension cord?

Any further thoughts on this, gang?

BTW, got a Monaco amp stand with the carbon shelf and footers from a fellow 'Goner yesterday- wow! Sort of like
taking your car out of the mud and driving it on smooth, fresh pavement. The fact that it is gorgeous doesn't hurt,either.

This noise problem is driving me a tad crazy, though.

(OH, yeah, I'm supposed to get my new TT today too, so
at some point, this system is going to reach its potential).
The 60Hz hum in the subs may be from poorly shielded or oriented power supply transformers in the sub cabinet. I belive the Avantgardes use internal amps for the subs, yes? If they do, have you tried running them straight off the wall socket with no filtering? If you get a similar 60 cycle hum, you've got an inernal noise source--that is, the mains transformer. Opening the speaker (yikes!) and carefully shielding the transformer with ERS cloth (*don't short anything*) or similar could help. A more simple method of banishing such hum from a component builder's perspective is to change the orientation of the transformer. In other words, unmount it from whatever it's attached to and simply turn in from it's origial mounting position and listen for changes.

If the mains transformer is in a separate chassis from the subs, you can try similar things and it's easier since you don't have to open the speaker.

Not sure about the sound from the horn, but it doesn't sound like a tube issue as the volume doesn't increase with settings.

Hope this helps--we all can get a bit neurotic about this. As I recently said to my audio bud, this sometimes seems more like a support group than a hobby group.

Thnx Doug. Interesting angle. I'll call my buddy Jim Smith about that- he was the importer 'til recently.