Parasound Halo P3 Hiss and Hum

[Ned2865]

I've been reading threads on this forum for quite some time now but this is my first post. I'm new to this forum but not into the audio world. I bought a Parasound Halo P3 preamp in june of this year and I really like it It replaced a Cambridge audio C500. The first time I turned it on, I noticed right away a faint hiss as soon as the volume went up to the first step (without any music and whichever source was selected). This is absolutely normal until I have to put my ears close to the tweeters, like 6 inches. But since a few days, I noticed a "hum" coming from the midranges, not really a hum from a ground loop cause it's above 60 Hz. I don't hear it from the woofer but from the mid's, so I guess it's around 1 Khz. I use balanced outputs but I tried with unbalanced and still the same. Changed amplifier and still there, so it's definitely coming from the preamp. Anyway, it appears as soon as the preamp is turned on. I moved everything to another room and still doing the same. Maybe it's normal, I can't tell. Just like that hiss, I have to be really close to the midrange to ear it. If anyone owning a P3 can spot check that issue and tell me more about it, that would be appreciated. If there's something which can be done or checked, I'll do it. Thanks in advance for you responses.

[Pat D]

I've been reading threads on this forum for quite some time now but this is my first post. I'm new to this forum but not into the audio world. I bought a Parasound Halo P3 preamp in june of this year and I really like it It replaced a Cambridge audio C500. The first time I turned it on, I noticed right away a faint hiss as soon as the volume went up to the first step (without any music and whichever source was selected). This is absolutely normal until I have to put my ears close to the tweeters, like 6 inches. But since a few days, I noticed a "hum" coming from the midranges, not really a hum from a ground loop cause it's above 60 Hz. I don't hear it from the woofer but from the mid's, so I guess it's around 1 Khz. I use balanced outputs but I tried with unbalanced and still the same. Changed amplifier and still there, so it's definitely coming from the preamp. Anyway, it appears as soon as the preamp is turned on. I moved everything to another room and still doing the same. Maybe it's normal, I can't tell. Just like that hiss, I have to be really close to the midrange to ear it. If anyone owning a P3 can spot check that issue and tell me more about it, that would be appreciated. If there's something which can be done or checked, I'll do it. Thanks in advance for you responses.

Do you mean your new Parasound preamp is noisier than your Cambridge Audio one? If so, I'd take it back! What does it do that the old one didn't?

Audio electronics all produce some residual noise, and in fact, most have specs for residual hum and noise. I would be surprised if there were not a noise specification in your owner's manual. Some electronics are lower noise than others, of course, and there's nothing the matter with overkill. As long as the noise is inaudible from your listening position at the volume settings you normally use, it should not be a problem. If you have to put your ear close to the speaker to hear it, it definitely is not a problem.

[Ned2865]

Do you mean your new Parasound preamp is noisier than your Cambridge Audio one? If so, I'd take it back! What does it do that the old one didn't?

Audio electronics all produce some residual noise, and in fact, most have specs for residual hum and noise. I would be surprised if there were not a noise specification in your owner's manual. Some electronics are lower noise than others, of course, and there's nothing the matter with overkill. As long as the noise is inaudible from your listening position at the volume settings you normally use, it should not be a problem. If you have to put your ear close to the speaker to hear it, it definitely is not a problem.

Pat, I agree that this faint hiss is normal, you can't hear it from a normal point of listening. That preamp has a digital volume instead of the analog one on the Cambridge. Volume set to "0", you don't hear a damn thing. When stepped up to the first step (which is "2"), that hiss is already there and stays at that same level until "80" max volume is set. That is normal. What is abnormal is that buzz coming from the midrange. If I noticed that hiss at first, I would have notice that buzz too, but I noticed that since a few days ago and that is not normal. This unit meets all the company specification BUT that buzz wasn't there since lately and that's what I wanted to check out with some other P3 owner

[Peter_Klim]

You may want to read the review in the link below that contains this text:

"Once everything was connected, I turned the P 3 on. As the preamp powered up, I could hear a hiss in the speakers. I had not expected this as the Simaudio unit is dead quiet with both the balanced and unbalanced inputs. The only time the hiss disappeared was in the volume's lowest position or when mute was engaged, and in both of those cases the speakers became dead quiet. I did try the ground lift switch on the P 3 but it did not make any difference. The hiss is only noticeable a couple of feet from the speakers and should not affect music reproduction at low listening levels or in highly dynamic recordings, unless you were sitting 3 feet from the speakers."

from:
http://www.hometheaterhifi.com/volum...r-10-2002.html

I listened to this pre myself, but not with any familiar components, so I can not give you a fair review on its sound quality. But, I did notice the hiss as described in the review. My thought were: "For an $800 pre, I shouldn't be getting ANYhiss at all." That is one factor that helped me decide in not to prchase this pre.

The other is that there are not that many steps to increment the volume (I'd prefer an analog knob with continuous variable control). the other is that I heard other reviews of that hu, The otther is that I heard (from a few sources, including some reviewers here at audioreview) that when people touched the volume knob, a static charge was created that caused damage to the unit (I think it was the IC chip in the volume control). But yours should not have that problem, as the newer models have a fix to this problem.

I am sure that the unit sounds as good as all the reviews say it is. But I don't want to take a chance in purchasing a unit with so many issue (who knows, I may still change my mind).

I hope I didn't bring you down. But here are some more positive reviews:

http://www.audiorevolution.com/equip/halo/
http://www.stereotimes.com/amp040803.shtm

http://www.audioreview.com/Preamplif...x.aspx#reviews (some reviews here talk about the volume defect)