Those magical days when the HVAC is off

@ostemo8 I didn't mean to hijack thread from your electrical concerns to the noise issue, AC quality is an important issue, its just that its common to see threads attendant to electrical noise on AC grid and or home AC, I see very few threads on the environmental noise issue. Outside of the audio equipment itself, AC quality, listening room treatment and noise pollution (both home and external generated) are equally important for maximizing system potential.

The most irritating thing about ambient noise levels is often one has very limited control over it. Rock-on has great ideas for minimizing it, but many of us don't have option to implement all of those ideas. You can turn off your HVAC at certain times, but other times you just have to put up with it, the issue is once you've experienced those magical listening sessions when ambient noise levels were at their lowest, subsequent listening sessions with higher ambient noise levels may impact your enjoyment.

Doesn't bother me at all.  Equipment is manufactured to be so silent that the sound quality is not compromised.

Happy Listening.

My system is on all day for my wife's background music. The HVAC runs around the clock in summer (southern Nevada). One benefit of class D that people overlook is the much lower amp draw. I had an electrician look over my 500 watt class D system and he said it was nowhere near unsafe or needing any special wiring. We're on a solar net metering plan trying to go net zero. 

We demand space, price, and energy efficiency from all our residential systems including audio. It is producer degree of difficulty, technology, simplicity. Our Yamaha NS-5000's are an example: 3.5 pound woofer coils with proprietary carbon fiber in all three drivers in a 600 watt studio monitor built and painted in a piano shop.

@bigkidz +1

On another site a member was chest puffing about all the money he spent on his dedicated listen room, dedicated lines, and equipment, but then stated that he needs to disconnect his refrigerator to maximize his listening experience. Obsession for some