And I would think so
Originally Posted by mhdiab
If the furnace runs 95% of the time would your answer still stand? I would think not
MCACC is NOT supposed to be used with a lot of background noise. It clearly states that in the manual and it even checks for ambient noise in the setup.
Let's think about this and use some common sense here. Let's say the furnace sounds are in the mid to upper midrange frequencies.
The receiver pink noise (or white, I don't remember which) test tones include those very same frequencies. So, you have random mid's coming from the floor or ceiling still being picked up by the mic. All the time, it's measuring those frequencies and altering the speaker output to try to match some target curve. Your speakers are being adjusted in a way that artificially masks their true response and the response of the room. In ways that aren't even predictable.
At face value, the least it would do is LOWER the speakers mids because it senses more of them than normally would be present.
Perceived loudness & clarity, especially of dialog and critical mids, would be then be thrown off from what it would be normally. Depending on one's hearing, and females typically have better hi freq response than us men, if the mids are reduced, then the highs & lows may be perceived as louder or harsher.
On top of impact to the freq response, the noise coming from various places in the room will be picked up by the mic and could partially mask the reflected clicks used to accurately
measure speaker distance & delay times.
I don't see how anyone with any knowledge of how these auto cal systems are supposed to work could have any doubts about this.
Furnace noise, air conditioners running, appliances, car running in the garage, sirens down the street, airplanes flying by....it plain doesn't matter...the noise could reduce the accuracy of the room measurements.
That's why ALL the manufacturers tell you to do the calibration when it's quiet or low ambient noise.
If accuracy of measurement is not the goal, then there's no point in using a system like MCACC or Audyssey in the 1st place.
And if you think you're compensating for having the furnace running all the time, you certainly are altering the freq response, but whether it's a positive change or not is another matter. And you have introduced a factor that could interfere with the accuracy of all the measurements used to calibrate the speakers for optimum soundfield & blending of channels.
I've seen changing my own position in the room, adding a blanket on the couch, or move the mic 6" change some of the EQ and channel levels.
The measurements are best taken in quiet and if you want to tweak the settings, do them manually like CHP_VR says and save as a custom setting.
My advice is do like I do, try turning the AC/furnace off for serious watching/listening or turn the volume up when it's running