Don't have my 950 yet, but am anxious to see what kind of results I will get. I battle hum and hiss in my system. I have cheater plugs on my amp for ground loop hum (disconnecting the CATV didn't help at all). I also have experienced LOUD hiss from the center/surround preouts of my HK receiver and from the same channels on an Adcom Pro-Logic preamp.

I am really hoping the 950 will be quiet enough in my set-up. If not, I may be forced to try something like a balanced power transformer (best deal I have found is from b-p-t.com). Still not sure if the benefits of balanced power justify the cost, but it sounds like a great idea. Anyone here know about using balanced AC power for reducing noise in AV systems? Both Outlaw and BPT have 30-day money back guarantees. That doesn't leave a lot of time. Maybe I should order the power unit when my number for the 950 comes up?

After reading this thread, I went and listened to my existing system (on the wait list for 950...). I have a Denon 2800 and PSB Image 6T's.

Sure enough, I can hear a noticeable hiss with the receiver on but no sources on-- but only with my ear an inch or two from the speaker cover at the tweeter. So I suspect this is pretty common (see review on the Rotel RSX-1065 in Sound and Vision April 2002 issue). They use a test signal to measure the noise floor. BTW, I am considering the Rotel RSP-1066 as competition to the 950.

But if people are hearing it from 8 feet away (or even 1 foot), that is not OK. The hiss level on my Denon was not enough for my Radio Shack sound pressure meter to register even when pressed right up against the speaker and set to the bottom range.

Outlaw Admins, we would sure appreciate it if you would comment. I am keenly wondering what the answer is, as others probably are on the wait list...

Thanks.
-HTLearner

Test Results.
950
Acurus A200X5
B&K EX442
Snell D's
Sony DVP-560D

This system has zero power humm.

DVD,Coax,Stereo

Dead quiet on start up, no change with volume adjustment.

Play DVD, Pause: Definite Hiss with ear 1-2" from tweeter.
Volume setting has no effect, same hiss at same level.
Power off DVD player. Hiss continues. No change.
Power off 950. Hiss gone.

Not really a major issue but it does appear to be real. The 950 performs as well or better than any receiver or pre/pro that I have auditioned. Hopefully this hiss can be isolated or explained.

Tom

Tom,

I sure would like to know a few things about your setup, email me the answers if you don't want to display here.

1) 950 xovers and speaker low freq -3dB spec (Snells)
2) room size
3) music (digital or analog pass-thru)

My 950 does not have the noise issue as reported by Perfect. I cannot hear any hissing sound from my listening position and the only time I can hear the hiss is when I put my ears up to the speaker after I used the 950. However, if I start my 950 fresh with no source on, I get nothing but silence. And even after I turn on my sources, before I actually play anything, there is still no noise coming out of the speakers. Even if I turn the volume all the way up, there is still no noise.

I have the 950 hooked up to an Acurus 125x5 amp and going into the 950, I have my DVD player and VCR. The DVD player is connected using both a digital coax and Outlaw's PCA through the stereo out. I am also using a line conditioner, a Panamax 1000+. My cable use to cause ground loop feedback but the Panamax 1000+ has taken cared of that. I have not try to test for noise without the Panamax and I probably won't because I'll have to get a power strip.

As far as I can tell, the 950's noise floor is not only NOT the first real bad news but it is IMHO the first GREAT news about the 950. For both music and movies, the 950 is always chrystal clear and the noise floor is so low that sound just floats in the air.

Perfect, I hope you will be able to isolate the cause of the noise problem be it the 950 or not. As a suggestion, have you consider looking at the interconnect between the 950 and the amp? I have had an expereience in the past where I was using some unshielded Kimber PBJ cables from the pre/pro to amp that caused the speakers to hiss. Please share with us your findings when you've made more progress. Thanks.

[This message has been edited by mxy15 (edited May 06, 2002).]

Thirty year old power wiring and 25 year old CATV cabling has kept me battling ground loops in my system for years. Regardless of the processor/amp combination, I have always noticed the presence of hiss in my speakers, but only when I've had my ear against the speaker, troubleshooting the hum problem.

The hiss is more noticeable when I have the 60hz ground loop hum under control. But in no case have I ever been able to hear the hiss outside of an inch or two from the tweeter. This is true of both my 950 beta unit as well as my MC-12.

The ground loop hum has been the only problem since, uncontrolled, it can be heard anywhere in the room, with a silent house. I've never considered the hiss a problem since it is inaudible outside of an inch or so from the tweeter.

Those who have audible hiss at the listening position likely have a system problem or perhaps a defective unit. However, nothing in this thread or in my experience with the 950, leads me to believe that hiss is any more of an issue with the 950 than it is with any other digital pre-pro.

Regards - Gene

bstan,
1) 950 xovers and speaker low freq -3dB spec (Snells)40-22K,(small) 950 xover 60.
2) room size 20X20
3) music (digital or analog pass-thru)
digital.

Just tried analog input from CD player.
Hiss is present but now varies with volume control. Same with passthru.
Tom

Hey Guys,
I have ZERO hiss/hum. Every component I have either goes thru a Monster HTS5000 MK II Power center or a Mitsubishi Diamond series UPS. Power/Line conditioning may be why I have no problems. I don't really count the w/ my ear pressed against the tweeter as noise you can hear but I did do this and still hear absolutely nothing. I am using digital optical in. RP-51 panasonic for both DVD and CD playback at the moment.

------------------
Stott

I got the hiss in my main ,and do not change with volume.The hiss from my main is not a problem because I am about 12 feet from them.My real problems are the surround ,there are about 3 to 5 feet from me(depend of my position in the sofa),is really loud with every mode ,including input from the dbs receiver(sony hd100),pioneer dvd 47-a(dvd-v,sacd or dvd-a).My connection: optical dig from dbs,coax from dvd.Connection from pre to amp :transparent cables. Before the 950, I was using a Denon 2800 as apre tomy B&K 7270 without this noise.

Have any of you tried using a different power cord? Sometimes a high quality power cord will lower the noise floor and get rid of the hiss. I used an MIT Zcord II on my old rotel and the his was gone after I replaced the stock power cord.