Does delay really matter?


After more years than most in HT (started back in Laser disc days) I have become curious about delay or distance settings for speakers in surround.
I have been through lots of gear from Pro Logic to 5.1 and now up to 7.2 (have not felt a reason to go 9.1).
After going through the early years of recievers rangin from your Sony, Pioneer to statement Onkyo, then the move rto seperates years ago, Rotel, Parasound, Classe, Leexicon and now Anthem I wonder how much does the dealay matter?
I am in a dedicated room 13x24 with "ideal" placement of all speakers and after messing around with delay settings I have come to the conclusion I cant hear it, further more I would bet money nobody could tell if mine were set properly or not.
Does it only matter in huge rooms? I have heard some say set them, and some say leave them all at zero so what are your thoughts and experience? Thanks
chadnliz

07-15-10: Jylee
I'm sure I can hear the difference if my left speaker is 2 ft closer to me than the right speaker. I'd imagine the human threshold is much smaller.
If you are listening without delay or level compensation, yes. The 2msec threshhold (not absolute) applies to delay issues only.
I'm sure I can hear the difference if my left speaker is 2 ft closer to me than the right speaker. I'd imagine the human threshold is much smaller.
My experience has been that the use of delay is particularly important for subwoofers, to minimize the potential cancellation of the sub's output with that of the FL and FR speakers.

For a simple demonstration of this, you can use a SPL meter to measure the combined output of your sub and FL/FR speakers, using a test tone at the crossover frequency. As you change the distance (i.e. the delay) of the sub, you will see substantial increases/decreases in the SPL level, reflecting changes in the summation/cancellation of the sub with the mains. As Shadorne mentioned, differences of 2 feet are both measurable and audible, particularly with music.
Human threshold is about 2 msec or about 2 feet - so yes it does matter as many setups are more than 2 feet beyond the equidistant setup.
"Perfect" implies that all the speakers are equidistant from your ears. The delay is only important if they are not. The delay compensates for any difference in distance so that the sound reaches your ears at the precise moment from all the speakers. I also think that with movies it is harder to hear the difference than with multi-channel music.
If your speaker placement is "ideal," you should have no need of delay settings. No?