OK, I'm sure this is going to bring a storm of replies and generate a lot of heat here in the forums. Please realize up-front that is not my intent; I am merely reporting what I am hearing here on my 950.

After hooking up my system last night, I had my head near one of my front speakers and I noticed it hissing quite a bit more than I was used to. I figured maybe it was my amplifiers, and that it was probably time to upgrade them.

Flash forward to today, where I decided to investigate this issue a bit further. The hiss is still there, and I think I've actually tracked down two distinctly different noise floors on the 950. Below are my observations.

Working with my Onkyo DVD player connected optically to the 950 via Optical Input #1, we begin.

Turning on the 950 fresh, with the volume set to -80dB, I hear a very very faint hissing and a very slight upper harmonic of a 60Hz hum. This is what I considered the normal noise level for my old system (dodgy power, and I live within a couple of miles of a fairly powerful FM transmitter). It's barely audible when I'm sticking my ear within 1 foot of the tweeter.

Turning the volume up to -30dB, I begin to play a music CD. The 950 is set to Stereo mode. The trouble starts when I pause the DVD player. The hiss coming from the speakers has increased dramatically from the "cold start" condition. This hiss is audible from several feet away from the speakers. If my room is quiet enough, I can hear it slightly from my sweet spot about 12 feet away.

Repeating the experiment using my CD player. It's hooked up to optical #2 on the 950. Also set to "Stereo" mode. Again, starting up the 950 "cold" set at -80dB, the noise floor is what I consider to be normal for my system.

I start the CD playing. The volume is still set at -80dB. The first "click" on the volume knob to -79dB kicks on the hiss. It goes from what I consider to be normal to something much higher than normal. The hiss does not get louder, even as I take the gain all the way up to 10dB.

The hiss does not go away by dropping the volume back down to -80dB, nor does it go away by stopping the CD player. I _can_, however, make it "reset" by flipping to a source with an analog input. This drops the noise floor back down, and I can repeat the above experiment to bring it back up again.

The very last experiment goes back to the DVD player. I added an analog connection from the back of the DVD to the DVD analog inputs on the 950. I started up the 950 cold again, with the volume at -80dB.

Leaving the volume at -80dB, I started the CD. Same "normal" level of noise. I then hit "Stereo Bypass," thinking this might work around the noise. As I clicked from -80dB to -79dB, the noise level still increased!

Another point of information is that the "mute" function does not affect this noise floor at all.

I'm not sure what to make of all of this yet, but it's the first really significant problem that could take this product down from the stratospheric heights which it has obtained in some reviews so far.

If I get ambitious this evening, I'll grab my oscilloscope and see if I can get some noise floor measurements. Stay tuned.

My fingers and toes are crossed for good news.

LQQK

There's a conversation going on on HTF on the same topic. A few folks are participating. Good discussion so far.

http://www.hometheaterforum.com/htforum/showthread.php?s=&postid=662611&t=6826#post662611

I just ran the same sets of experiments with my DVD player hooked up to optical1, input mode set to stereo, and CD as source. Sure enough, I could hear the hiss when the CD was paused, and I could hear the hiss on the switch from -80dB to -79dB as well.

The hiss was faint and I don't think I could hear it from more than a few feet away, but it's definitely there. (Prior to upping the volume from -80 to -79, I couldn't hear any background noise, which is usual for my system, so the hiss is obvious, especially when the CD is paused, or skipping between tracks, etc.)

I didn't try any of the other experiments but I have little doubt the results would be the same.

I've run the same test and noticed a louder then normal noise floor. I actually had one of the first shipments from the beginning of April and I also noticed a louder amount of hiss coming from my speakers as soon as I plugged it in. I was running a Yamaha RX-V3000 with a Parasound 2205 amp and I never noticed any hiss, even at really high volume. However, with both of my 950s, April 4th and the new April 30th shipment I do notice much more hiss coming from my speakers. It is definitely coming from the outlaw. I have run numerous test and even switched back to my Yamaha. I'm not sure if it is normal or a problem. Overall, I'm very happy with the 950, however for a product that is supposed to be ultra clean, I find it odd to have way more hiss then my receiver.

Dan

Anyone try a coax DVD input yet?

Also, interesting data point about the TA-E9000ES I have. You can *set* the connection (opt, coax, or analog), or have the unit "auto detect" for it. If you *set* the connection, the noise floor is a lot lower than "auto detect".

In either case, can't hear it at my listening position though. (8 ft away.)

Hopefully the Outlaws can address this...

Prefect,

Let us know what the oscilloscope says. I've got my dvd hooked up via coax and can hear what sounds like a 60hz buzz to me, when the dvd or cd is paused. Of course, I have everything connected with crappy wires (temporarily), a not so glamorous surge protector (also temporary) and I have never mapped the circuits on this house. AFAIK it could be line noise.

Thanks,

Allen

Well, I fear the oscilloscope is the wrong tool for the job. I fiddled around for a bit last night and couldn't show anything conclusive with the 'scope.

So I'm going to see if I can call in a favor or two and get an Audio Precision One audio analyzer on loan for an evening.

Over on HTF we have another person reporting that they can replicate my experiment, and another person claiming they can't hear any hiss at all.

For what it's worth, the speakers I've got hooked up to the 950 (PSB Stratus Silver i's) are less sensitive than the speakers I used to use with my old preamp & amp (Klipsch KG-3.2's).

Perfect,

You should be able to see the noise relatively easy with the oscilosope on the pre-outputs (I'm not sure if they have to be loaded though). It will not be calibrated so you won't be able to tell how much noise is there in dB, but you'll see it. When the volume is at -80, you'll see almost straight line on the scope. When you turn to -79, you should see the noise to appear. Set the scope to around 50-500mV range. It would be more interesting of course to connect a spectrum analyzer to see what the noise actually looks like. I mean, is it totally random or has some shape.

If the noise does not depend on the volume setting, I wonder where is it coming from. From someplace after the preamps? After the volume control? Strange.

FWIW, the hiss on my 950 has a measurable maximum sound level of around 54dB on my radio shack meter. (Meter set to its lowest setting of 60dB, lowest setting, and the needle ranges between -10 and -6.) But that's with the sensor immediately in front of the tweeter. At a foot away, it's too low for the meter to detect.