Quote Originally Posted by Bruce B View Post
I thought sound travels at exactly the same speed whether it's 40Hz or 4kHz???

If you are trying to align the speakers/subs at the apex of the wave, say 25Hz, then it will ONLY be aligned at that particular freq and its multiples (50, 100, 200........)

Oh crap..... it's not aligned at 63Hz..... what's an audiophile to do?????
The reason that is true is only because speaker drivers are not linear in phase. If the cones are exactly the correct point where they can radiate from the same distance then everything would be time aligned. But the fact is they move, and the movement changes the relationship. Between a tweeter and a midrange/woofer this is a much larger difference than a midrange/woofer and subwoofer, because the wavelengths much shorter between a tweeter and midrange/woofer so the smallest of changes exaggerates differences more than when you're talking about long wavelengths with the subwoofer and midrange/woofer.

And that's my whole point that it's comical to be worried about small wavelengths difference in timing between a midrange/woofer and subwoofer, compared to a tweeter and midrange/woofer. You already experience it, all the time, at bigger differences, by huge amounts, in the more critical ranges of tweeters and mids.

If you're meaning phase alignment for peaks, well that simply cannot be without just playing tones instead of music.