Originally Posted by rosstg
One thing I don’t understand is why it’s best to put a blanket down to avoid reflections. I have a Teak coffee table between my large sectional with ottomans and tv stand. I’ve been putting a blanket over it when I calibrate as others suggested but doesn’t it make more sense not to cover? Shouldn’t the room be EQ’d as is to compensate?
I think this is another one of those pesky YMMV questions. It has always made sense to me to put a temporary blanket over a chair back, due to proximity to the Audyssey microphone, which doesn't "hear" sounds in the same way that we do. But, that is based entirely on close proximity to the measurement microphone. High-frequency sound waves, bouncing into the omnidirectional Audyssey mic, from close range, can cause Audyssey to try to overcorrect those frequencies. And, that can potentially create a harsher or more shrill sound.
Treating first reflection points, between the speakers and the listening position can also make sense to me, as the smooth surface of a coffee table can reflect higher frequency sounds toward our ears, causing distortion. Putting some kind of throw, or scattering some magazines, on the table can help to absorb or disperse those early reflections. But, those are more-or-less permanent solutions, intended to improve our overall sound quality, whether we are using Audyssey or not.
Putting a blanket on a coffee table, only during calibration, and then removing it afterward, could potentially help to prevent Audyssey from overreacting to the early reflections. (We don't want Audyssey trying to correct too much for reflected sounds, if we can help it.) But, it won't do anything to prevent us from hearing those early reflections ourselves, once we take the blanket away. So, it could make theoretical sense, strictly from the standpoint of the Audyssey calibration, but it may or may not make an audible improvement in the actual post-Audyssey sound that we hear.
I don't, at the moment, see where the temporary blanket would do any real harm. I'm not sure of that, but I can't immediately see where it would. But, I think that this issue is one that probably has to be settled on a case-by-case basis. If I were really curious about this question, I would try calibrating with the blanket, and listen for a while, and then try calibrating without the blanket, and listen for a while. (Try hard to keep the mic positions as close to exactly the same as you can.) I'm not convinced that you would be able to hear any real difference between the two calibrations, but if you did, you would just pick the one you like better.
My personal recommendation would be to put something on the table to absorb or diffuse higher frequencies, anyway, and keep it there all the time. I believe that may make a positive difference in your overall sound quality.