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<blockquote data-quote="Ivan Beaver" data-source="post: 57567" data-attributes="member: 30">Re: How to build a flat-phase DSP preset?Here is a link that talks about the basic concept-in simple terms.<a href="http://www.danleysoundlabs.com/danley/wp-content/uploads/2012/01/The-Tapped-Horn.pdf" target="_blank">http://www.danleysoundlabs.com/danley/wp-content/uploads/2012/01/The-Tapped-Horn.pdf</a>It all STARTS with having the drivers in the proper position to each other-not only to keep the expansion rate correct-but also the physical distance between them for the particular passbands.This makes the crossover design a bit easier.&nbsp; Since the drivers are always the same distance from each other (in different listening positions in the coverage area) the phase and freq response does not have the errors in it that designs that have offset drivers do.The crossovers in the Danley cabinets are not trival (some more complicated than others).&nbsp; For example in the Sh50-there are basically 4 (kinda) &quot;crossovers&quot; on the high freq driver alone.&nbsp; The highest one is around 17Khz.There are some &#039;unusual&quot; things going on-that at first do not make sense-but aid in the overall response.&nbsp; When I first saw it-I told Tom he had messed up on the crossover design.&nbsp; Why would anybody put a 12dB/oct LOWPASS filter on the high freq driver?&nbsp; Well the reason is to ADD more high freq via the crossover.&nbsp; He told me to remove it and see what happened-and being the doubting Thomas that I am-I did.&nbsp; And the HF response went DOWN! ie didn&#039;t extend as high.&nbsp; Another one of those learning moments for me.I won&#039;t go any further than that-but we use the same process on a number of our cabinets to extend the top end.The more &quot;flat&quot; the phase response is-the more the cabinet will sound like a single driver.&nbsp; If you can&#039;t see from the phase response where the crossover points are-then that is good indication of a good alignment.</blockquote>

[QUOTE="Ivan Beaver, post: 57567, member: 30"] Re: How to build a flat-phase DSP preset? Here is a link that talks about the basic concept-in simple terms. [url]http://www.danleysoundlabs.com/danley/wp-content/uploads/2012/01/The-Tapped-Horn.pdf[/url] It all STARTS with having the drivers in the proper position to each other-not only to keep the expansion rate correct-but also the physical distance between them for the particular passbands. This makes the crossover design a bit easier. Since the drivers are always the same distance from each other (in different listening positions in the coverage area) the phase and freq response does not have the errors in it that designs that have offset drivers do. The crossovers in the Danley cabinets are not trival (some more complicated than others). For example in the Sh50-there are basically 4 (kinda) "crossovers" on the high freq driver alone. The highest one is around 17Khz. There are some 'unusual" things going on-that at first do not make sense-but aid in the overall response. When I first saw it-I told Tom he had messed up on the crossover design. Why would anybody put a 12dB/oct LOWPASS filter on the high freq driver? Well the reason is to ADD more high freq via the crossover. He told me to remove it and see what happened-and being the doubting Thomas that I am-I did. And the HF response went DOWN! ie didn't extend as high. Another one of those learning moments for me. I won't go any further than that-but we use the same process on a number of our cabinets to extend the top end. The more "flat" the phase response is-the more the cabinet will sound like a single driver. If you can't see from the phase response where the crossover points are-then that is good indication of a good alignment. [/QUOTE]

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