PWD Noise Floor

I am wondering about the inherent noise floor of the PWD. When I turn my dac on it used to contribute an audible hiss that if I remember correctly could just barely be heard at my listening seat about 8 ft from the speakers. I say, “used to” because I lowered the gain significantly on my Hypex amps so the hiss is now only audible very close to the tweeters. I know that some hiss is expected from most amps but does this sound like normal PWD behavior? I am thinking something may be amiss…

PWD noise floor should be something greater than 120 dB below maximum output as I remember. Exact number uncertain, but between 120 and 130 dB. Of course, you don’t want to rely too much on my memory, the answer is buried somewhere in these forums. :smiley:


nile49, this sounds unusual. My system is very quiet when no music is playing, and the addition of the PWD did nothing to change that. Is the PWD plugged into the same outlet or circuit as the rest of your source gear?

Yes it is on the same circuit.

Curious. Do you have the opportunity to try multiple PWD inputs?

Yes I agree, I have essentially no sound with my ear close to the spkr. But my Mini is DC and I have a couple of P.I. Audio’s noise filtering gear which helps I am sure.


I do, and will see what I find tomorrow.


The noise floor is about the same between inputs when the connected components are on. For instance when I select toslink but do not have our connected PS3 turned on it is basically silent, but when it is on it is only slightly quieter than the other inputs. The same is true with USB and my Mac Mini although I would say that that input is fully as noisy as the bridge input. The bridge input retains the same noise level regardless of whether or not the ethernet is connected.

Hmm, I’m not sure what else to suggest. :-?