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Discussion Starter · #1 ·
OK I've read all I can find on this, and think I understand the basic principle of time alignment. Basically it adjusts the delay times from each speaker so that sounds meet simultaneously at the listener, I get that. But I'm a nerdy noobie, and I always make **** complicated so here goes.

But there are 2 things still bothering me.

1. would you want all frequencies to be synchronized at the listener, or would a more sophisticated system be able to selectively delay by frequency. In other words say I'm running 2 way components plus a sub. Is it optimal to adjust each speaker for distance, like I could achieve with a phase knob. Or would I want to set the tweeters out farther than the mids, etc. Or would a digital time alignment device like a bit one be able to delay different parts of the frequency band in finer detail to achieve some kind of enhanced imaging? Reason I suspect this is I have had home stereos in the past that have imaging knobs which move the sound stage out and in, while using only 2 speakers! (It can't be just delay with only 2 speakers, delay is relative, has no meaning in a 2 speaker system) So there must be some kind of voodoo that goes beyond making speakers sound equidistant from the listener. It must be related to enhancing the differences between right and left channels that makes stereo sound stereo.

2. Is phase shift another way of expressing delay or is there more to the story? I can't understand how they're related. I mean, sure they directly convert back and fourth for any one given frequency, but music is made up of the sum of countless frequencies. I mean for example, if you phase shift a 50 hz signal 180 degrees you would delay 10 ms (that's 1/50 = 0.020 seconds per cycle from peak to peak, 0.010s peak to trough). But riding along with that 50 Hz signal is also a 5000 hz signal, to phase shift it 180 degrees you would delay 0.1 ms. (1/5000 = 0.00020 seconds or 0.2ms so you would delay 0.1 ms to phase shift a 5000 Hz signal 180 degrees.) ??? WTF am I missing ???

I'm trying to soak up all I can on this before I jump in on a purchase. My goal is to buy just enough flexibility to make top-class sound quality. I don't mind if it needs manual adjustment, and takes lots of time, etc - I even prefer it due to lower cost and less chance for computer control glitches, windows xp/vista/7 compatibility nightmares, etc. Just want to make sure I will get what I need in a simpler analogue system like a pair of ppi psc-221s.

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