How U determine first and second reflection points


Someone told me following a while ago in room teak thread, but I don't think I understand it well. Any comments?
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Have someone sit in the primary listening location, take a mirror to the side walls opposite each speaker and move it until the seated person can see the speaker reflected in the mirror. These are your first reflection points. Start from there.
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eandylee
Fmpnd - Ya snooze you lose guy. Sorta germain to this thread - mirro, mirror on the wall, who's the smartest....
;-)
No excuses man.
What were you supposed to be doing anyway? I'm "Working from Home".
Ah, C5150 - yes, in fact sound travels in straight lines - it's not real good at going around corners. Try having someone else stand in front of your speakers - see what I mean. Sound = straight line.
Reflections of straight lines = standing waves - not a good thing. Mirrors show you where they occur.
Nevermind, just go enjoy your instrument.
Oh - Zargon has a good point. The rear reflections are probably worse than from the sides. I've deadened both walls enough to tame that form of standing wave.
Tvad, I think we'd exhausted the subject anyway.

Well Cdc, If you want to see that first reflecting point on a permanent basis I suppose that's useful - why else would you want a mirror on the ceiling?