[Mijknarf]

Understood, thanks for the reply Ric.

Jim

[THWO]

versus rider wrote as answer to post #12:

if one driver is 100mm behind another that would be 0.333 of a millisecond out of time alignment I defy anyone to hear any difference, if anyone can then you have my sympathy for having such sensitive ears

Your seem to be right in this aspect. A time difference of just 0.3 seconds doesn´t seem to be much at first glance. However - what delay do you think we will start to hear? Half a second or less? I don´t know... This capability was pretty important some 10thousand years ago...

Another question my be wether a "true" H-frame woofer will be sufficiently done with just 10 cm depth on each side. Depending what lowest frequency you may be aiming at. If we came to, say, 20cm each way, a time misalignment would look quite differently. If we were talking half a second then, this may become an audible issue.

But it is less the eventual audibility of a time misalignment itself; what counts more will be the more or less serious dips and/or peaks in overall frequency response that will occur in the crossover range between woofer(s) and wide band. And you will have different negative effects in the front radiation (where the woofer is set back) and the rear radiation (where the woofer is "first") - both resulting in some unwanted coloration you may probably hear even without enjoying superman´s ears.

Regards
Till

[versus rider]

no not 0.3 of a second, 0.3 of a millisecond

versus rider wrote as answer to post #12:

Your seem to be right in this aspect. A time difference of just 0.3 seconds doesn´t seem to be much at first glance. However - what delay do you think we will start to hear? Half a second or less? I don´t know... This capability was pretty important some 10thousand years ago...

Another question my be wether a "true" H-frame woofer will be sufficiently done with just 10 cm depth on each side. Depending what lowest frequency you may be aiming at. If we came to, say, 20cm each way, a time misalignment would look quite differently. If we were talking half a second then, this may become an audible issue.

But it is less the eventual audibility of a time misalignment itself; what counts more will be the more or less serious dips and/or peaks in overall frequency response that will occur in the crossover range between woofer(s) and wide band. And you will have different negative effects in the front radiation (where the woofer is set back) and the rear radiation (where the woofer is "first") - both resulting in some unwanted coloration you may probably hear even without enjoying superman´s ears.

Regards
Till

[THWO]

Yepp.  Milliseconds, of course.

But it is the distortions in the frequency response of the crossover range, what I wanted to aim at. Having those distortions in two directions (the backwave different, probably worse) and both "working" on the same crossover range, we are talking about well audible effects here. Actively driven systems may correct this to certain extend - in one direction - but not in two at the same time. That´s all I intended to hint at.

However, if your personal design ideas prefer to overweigh the optical over technical issues, just go ahead. I do not insist in being right or that this (being a bit OT-) issue possibly was a "must"...   


Regards,
Till