Axiom Home Page Forums General Discussion Technical Questions Axiom and time coherent design?

Wouldn't hurt, although the article is pretty long and wordy.

Time-coherent design is actually even simpler than you guessed. With a tweeter, the cone is small and pretty much level with the front of the speaker. With a woofer, the cone goes in a couple of inches (more with a big woofer) so the sound takes a tiny bit longer to get to your ears. Time coherent design is just about making the drivers line up so they are the same distance from your ears.

I believe there is a tiny difference in speed of sound depending on frequency but it is REALLY tiny if it exists at all.

Oops...um....uh....maybe I should read it too

i used to have a pair of thiels that had that design,dont know how much of a effect it had on the sound,but they sounded great

Hey!....all in all a pretty good read.

I guess I should have at least read the first page of the article, where it explains that time-alignment is about aligning the drivers...not making up for "speed" differences.

I was incorrect.

I was in error.

I was wrong.

Please, don't anyone tell my wife about that last one there!

Your secret is safe with us...







..... for a price

Does this mean I should put a pair of Canadian hockey pucks under the front of my speakers?

John
Very interesting read. Thanks for posting that link.

Wow!!.....I was(sorta)right, and(sorta)understood the concept

Convincing the Wife of that understanding, however....

Bump... Here is technical explanation on why time/phase Coherence is mostly nonsense in loudspeaker design.

We’ve done a lot of research in the area. In fact when I made my first loudspeakers at Symdex in 1976, I thought that it was important because that was the fad at the time. With some people, it’s still a fad. But if you look at the way the human hearing functions, you’ll see that time-coherence isn’t important. I actually credit Dr. Stanley Lipshitz at the University of Waterloo with bringing this to my attention, to put it mildly, in the 70’s at Mirage. He and Dr. Vanderkooy came up with a box that would let you alter phase response without altering amplitude response, and by using it you could do listening tests to determine the audibility of phase errors, or time-coherence. It was quite evident then that if you are in an anechoic chamber or you are using earphones, you can detect the difference especially with special clicks that are made to hear it. You can’t always say which is right or better, and as soon as you introduce the room it’s 100% inaudible. The importance of phase is in the crossover region because that’s an indicator of the blending of the transducers that are being crossed over. So in and of itself it’s not a significant thing. And in order to try to optimize it you really sell your soul in terms of things we know are really, really important to sound quality. That is a key fact. It’s not like it’s cost free, audibly, to optimize that parameter.

http://www.hometheaterhifi.com/volume_11_2/feature-interview-kevin-voecks-4-2004.html