Speaker hiss with Simaudio Moon Evolution i-7 integrated amp

Cam -- Sat, 07/24/2010 - 19:55

Hi Folks,
I just bought a used Simaudio Moon Evolution i-7 integrated amplifier and I have an audible hiss from my speakers when I turn the amp on. It's not distracting when listening to music but it is much louder than the hiss I used to get with my NAD M3 integrated amp. The volume of the hiss does not change with different volume or source settings on the amp. I'm wondering if there is a problem with the i-7 that I need to get checked out or if it's normal. Simaudio says there can be a more of a hiss with their products than some others due to their "no feedback" Linx design, however I've heard others say the i-7's noise floor is extremely low with very "black" backgrounds. Ultimately I just want feedback as to whether this could signal a problem I should be concerned about and if I should see my local Simaudio dealer.
Thanks,
Cam

TOGA -- Sun, 07/25/2010 - 00:15

Hi, I use Moon P8 to connect with W7M, I also have hiss when I put my ear 3- inches from tweeter too, this hiss gone when I put preamp in
Mute mode. level of hiss is constant independent from volume level. I think all electronics will produce such hiss to a certain degree at
tweeter. For mine, just 6 inchese away from tweeter and it is inaudible, how about yours ?
Toga

Cam -- Sun, 07/25/2010 - 10:39

Hi TOGA, my experience is the same as yours. The hiss is independent of volume level and input setting and it disappears when I put the pre-amp in mute mode. It is only audible within a couple feet of the speaker but not from my listening position.
I've tried to play around with my interconnects and speaker cable (Cardas Golden Reference) to make sure they are well apart from each other and the power cords but it really hasn't made any difference.

TOGA -- Fri, 07/30/2010 - 03:14

Hi,
It's the noise generated from auio circuit, should not be big matter. I've heard it from Levinson 326s , Audio Research Ref 5 as well.
some tweeters are really sensitive and highly resolving, human ears too. So I think this is not a big matter. But read reviews of Simaudio P8 from Stereophile and it seems like the writer overrated it. He wrote that he heard nothing even his ear on speakers. But his speakers may have tweeters that is less sensitive.

TOGA -- Wed, 08/18/2010 - 21:10

CambasKey,
I think you will be comfortable to know that my new ARC top of the line pre amp, produce the loudest hiss form tweeter I ever heard
in my life !!! I've Mark 326s, Moon P8, XP20, ARC Ref5 in my system before, all produce clearly audio hiss from tweeters in 5" distance. But
this new ARC preamp make this noise a sound effect on music. it is worse on Right Ch. than on Left Ch. May be it's a nature of tube system.

john.knox@gmail.com -- Fri, 09/10/2010 - 09:55

I would contact SimAudio to see what they recommend doing to alleviate the hiss in your speakers.