Originally Posted by
maxdb 
Some things I've found when doing Audyssey and measuring the results with room measurement equipment afterwards is:
- The more positions you measure, the worse the result at the main listening position is likely to be.
- The farther ANY measurement position is from the main listening position, the worse the final result at the listening position.
- The fewer number of measurements you use, and the closer they are to the main listening position, the better the results at the main listening position.
- Always measure the main listening position first.
- If seatbacks block sound from the back or sides or if sound can reflect off the back of the seat and come back to the microphone, recline the back so it is below microphone level, and consider throwing a heavy blanket over it to kill reflections.
- The more measurement positions you use and the more spread-out the measurement positions are, the more "averaged" sound in the room becomes. This is generally HARMFUL to the sound at the main listening position, but may be somewhat or very helpful for alternative seating positions.
- Getting the measurement microphone set at ear level is important. This should not be guessed at - have somebody measure ear height for each listening/measuring position and use the measurements to set the microphone height.
- Putting the microphone on a tripod gives MUCH better calibrations than placing the microphone on a stack of books or magazines. If you don't have a tripod and don't want to pay for one. Use some putty or fun-tak or blue-tak to stick the microphone to some sort of stick you can prop up vertical. You don't want a large surface under the microphone.
- To get the best sound at the listening position, 1st position should place the microphone in the center of your head - between your ear positions. 2nd position should be close to one of your ears. 3rd position should be close to your other ear. If you want SOME improvement for the seats to the left and right of the main listener's ears, put the 2nd and 3rd measurements a foot or 2 outboard of the main listener's ears. And don't do more than 3 measurements. If you measure in front of or behind the main listening position, Audyssey will do it's best to improve sound over the whole measuring area and this WILL sacrifice quality at the listening position.
Hope this helps you get a better calibration!