OK guys - question... I was about to do the 'string thing', despite Mrs Keith looking on incredulously as I measure and prepare to cut a length of string
Here is the ETC of my centre speaker (Audyssey is on):
It shows a couple of nasty spikes. The first is at 1.44ms and the second is at 4.76ms. Using the formula on p63 of Jerry's guide gives me the following:
1.44 x 13.39722 is 19.29 inches, or 1.60 feet.
4.76 x 13.39722 is 63.77 inches, or 5.3142 feet.
Multiplying those by 1.13 gives me a total reflection distance of 1.82 feet and 6.00 feet respectively.
The problem is, in my room, it is impossible to have a reflective surface at those distances, given that the MLP (and thus the mic) is approx 9.5 feet from the centre speaker.
What am I missing before I break out my new ball of string delivered so efficiently by Amazon Prime yesterday?
EDIT: The example in the Guide doesn't make much sense either, because it shows a calculated distance of 8.6 feet and, again, that is way too short a distance from the speaker to the reflective point and then on to the mic. Something seems to be amiss...
Make the string:
9.5 + 1.60 = 11.1 feet and stretch to see where it will touch.
9.5 + 5.3 = 14.8 feet
see if that helps you identify.