A:Answer Basically, it is the white noise or other impurities the receiver puts out to the speakers.
The lower the percentage, the clearer the signal to your speakers will be.
It doesn't mean it fixes those noises from your sources, it just means the unit is rated to only add X percentage to it.
So, if your source is rated for 1.3% of noise, your HDMI cable input adds 0.7% and your receiver is rated for 1% THB ..... then your receiver is rated to add 1% of the source 2%.
In other words, you would end up with no more than 2.01% of electrical noise at the speakers. An amount our ears can't even detect among the sound field of Vin Disel driving a tank off a plane and landing it in a rubber fishing boat that turns into a submarine made of fastness wrapped in a furious blanket.
