Will: -Whoops on the Klispch.. and was teasing on the volume, would have to have an awfully big space for that 1812 at +5 but…. wouldn’t it be something…just up until you went deaf!

Seriously, Will I’ve been following your various hiss (now hums).
My info may be outdated resolved,etc but when I saw you mention you had a CG amp this week, it rang a bell on a memory of some info I had run into on Carver amps way back when I was looking for Class D or hybrid-like tech. I ran into this on the Sunfire Cinema Grands ( also affected were the ‘Signiture’ release of the CG) and another Carver design release I can’t remember. I pulled this from 2000/2001 consumer reviews.
These (hiss/hum)issues appeared in ‘some systems’ but not others, - with theories it could be traced in some systems to interconnect interactions, various model pre-pro/reciever interaction with the CG, etc. Some posters mentioned …the issue did not occur until they changed/added in their AV setup. Most posters who had these issues often never returned their amps (due to their great satifaction with the product) but attempted by tweaks/changes in their systems to minimise impact and declared their intention to "live with it" due to the great preformance/sound of the Carver design.


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Reviewed by: Gary , Audiophile, from los angeles,ca
Product Model Year:2001
…….btw, I also had that damn buzzing/ground problem……….
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Reviewed by: Chris Immormino, Audiophile, from Roy, UT
……when I first hooked up the unit I had a hum from the center speaker with my preamp in stereo only mode. Disconnected the cheap RCA cable I had used to connect the center and the hum went away. Replaced the interconnect with a Kimber cable Hero interconnect to match my mains and the problem is gone. I suspect the unit is very sensitive to interference and ground loops.
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Reviewed by: Adriano , Audiophile, LA
……… I am deeply bothered by this very audible hum. I thought it was an isolated problem until I read ….
Major humming. Problem…..
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Reviewed by: Jeff , Audiophile, SJ,CA USA
….When it was in standby, there was a hum coming from the amp (i.e., from inside the box). When it was on, there was a very obnoxious hum from all five speakers that clearly audible, even over music.
I was so bad that I thought mine had to broken. I returned it to my dealer, who let me borrow their demo unit to see. The demo unit was marginally better (hum not has bad, and not as bright), but still unacceptable. Thankfully my dealer allowed me to return it. My dealer plugged mine into their system and told me that it appeared to be fine.

My take on all of this is that the CG is VERY dependent on system matching, even though everything I tried couldn't solve its problems in my system.
On the plus side is that the CG through an amazing soundstage
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Posted by Anthony 9- 20 -1999 Using Mozilla/4.0 (compatible; MSIE 4.01; Windows 95):

This weekend I just purchased the new SUNFIRE CINEMA GRAND SIGNITURE AMPLIFIER...I was an earlier owner of their CINEMA GRAND AMP.... It was not so apparent with the earlier Cinema Grand amp but now I hear a slight "hum" from the speakers when plugging in the new amp (is it quite possibly because this amp is so much more powerful and/or this amp has a 3 prong AC cord. My room is rather small so I am close enough to all my speakers and components to hear this hum in quiet passages of film soundtracks(mostly when there is just vocals present without background music or effects:especially T.V. news broadcasts)…
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Audio Revolution. -Sunfire Cinema Grand Series II Architectural
Reviewed by Jerry Del Colliano - July, 2002
The Downside
Despite design changes to make the amp more quiet relative to a signal to noise ratio, I still find the Sunfire Cinema Grand Series II to be noisy in comparison to amps that don't employ the Tracking Downconverter concept. If you want the power and the finesse at this price without the heat in a small package, you have to sacrifice something and that compromise is a tiny fraction more noise than you will hear on a Proceed AMP5 or other amps in the Sunfire Cinema Grand Series II’s class. For home theater applications, I don’t think this amount of noise is much of an issue, but for extremely critical musical listening, especially on more sparse productions like some jazz and small-scale classical albums, audiophiles might object to the ever-so-slight hiss
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Posted: June 28th, 2002
Andrew_Ballew
AVS
The ONLY component in my theater that has a 3 prong cord is the Monster HTPS 7000 Power Center. EVERYTHING else is two prong- my Carver amp, Rotel pre-amp, both powered subs, dvd player, etc. etc. My cable is grounded properly as well, so it is not the source.

I still have a slight hum or buzz from my speakers, even with everything off but the amp. So, I can only assume my hum comes from its internals, or the hum is introduced after the amplification stage in the speaker wiring. The hum still exists even when I unplug all input wiring to the amp.

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Any possibility this could be playing a role in the level of your hums/hisses??