"
I am still waiting for someone to tell me who can understand time-phase coherent, including all the experts in the world )-: :-("
That I can help with....
First understand "Time Alignment"
The speed of sound moves at the same speed at all frequencies, so the first battle would be to make the sound of the tweeter, mid, woofer or any other driver to hit your ears at the same time. The most common way is to align the voice coils, where the sound of the speaker originates from. When coils are in alignment, the sound from all drivers hit the ear at the same time. Could be done by staggering or a slanted front etc.
Next ... Phasing:
One reason that a single driver does so many things right is that there are no phase issues. A single driver does not have to move in unison with any other drivers.
So what is phasing? All drivers moving in perfect unison.... when one driver starts moving outward, all drivers move outward at the same time, when it comes back, all drivers move back at the same time. This helps tremendously to prevent smearing or to improve pinpoint imaging.
So what did I mean when I said that cross overs change phasing... A single cap or 1st order crossover, normally will cause a phase shift of 90 degrees, so to keep the next driver moving in unison, it must also be moving 90 degrees out of phase to stay in unison with the other driver.
Again, 24db per octave brings you back around 360 degrees to put drivers back in phase, but the crossover parts count, the sound of the crossover parts being used and the practice vs theory that you don't truly end of with absolute phase cause most to not use 24db per octave slopes.
Time/Phase Coherence is just what it sounds: Time and phase working in conjunction to form a Unified Whole.
I hope that I have expressed this in a way for everyone of any level to understand,
Tim
That I can help with....
First understand "Time Alignment"
The speed of sound moves at the same speed at all frequencies, so the first battle would be to make the sound of the tweeter, mid, woofer or any other driver to hit your ears at the same time. The most common way is to align the voice coils, where the sound of the speaker originates from. When coils are in alignment, the sound from all drivers hit the ear at the same time. Could be done by staggering or a slanted front etc.
Next ... Phasing:
One reason that a single driver does so many things right is that there are no phase issues. A single driver does not have to move in unison with any other drivers.
So what is phasing? All drivers moving in perfect unison.... when one driver starts moving outward, all drivers move outward at the same time, when it comes back, all drivers move back at the same time. This helps tremendously to prevent smearing or to improve pinpoint imaging.
So what did I mean when I said that cross overs change phasing... A single cap or 1st order crossover, normally will cause a phase shift of 90 degrees, so to keep the next driver moving in unison, it must also be moving 90 degrees out of phase to stay in unison with the other driver.
Again, 24db per octave brings you back around 360 degrees to put drivers back in phase, but the crossover parts count, the sound of the crossover parts being used and the practice vs theory that you don't truly end of with absolute phase cause most to not use 24db per octave slopes.
Time/Phase Coherence is just what it sounds: Time and phase working in conjunction to form a Unified Whole.
I hope that I have expressed this in a way for everyone of any level to understand,
Tim