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<blockquote data-quote="Peter Morris" data-source="post: 138651" data-attributes="member: 652">Re: Simplest delayIn this case I don’t think you can delay the HF driver without causing time misalignment and cancelation at the crossover point (I’m assuming Yamaha got this correct).If you are using an IIR or analogue crossover what happens as you approach the crossover point is there will be phase shift and an apparent delay.The phase of the HP and LP should match at the crossover.With a normal IIR crossover which is phase-aligned at the crossover, the bass will always arrive late.If you time align the LF and HF as is suggested (above), here there will be lumps and bumps through the crossover region. It is the result of cancellation caused by the LF and HF phases not matching at the crossover frequency.If you want a flat phase response and no “lumps and bumps” you need to use an FIR crossover. The cost is time, and the time needed is proportional the crossover frequency; the lower the frequency the greater the time required. It’s not a processing speed issue; it’s just the laws of physics. This paper may be of interest.<a href="http://dolby.invisionzone.com/index.php?app=core&amp;module=attach&amp;section=attach&amp;attach_id=7" target="_blank">http://dolby.invisionzone.com/index.php?app=core&amp;module=attach&amp;section=attach&amp;attach_id=7</a></blockquote>

[QUOTE="Peter Morris, post: 138651, member: 652"] Re: Simplest delay In this case I don’t think you can delay the HF driver without causing time misalignment and cancelation at the crossover point (I’m assuming Yamaha got this correct). If you are using an IIR or analogue crossover what happens as you approach the crossover point is there will be phase shift and an apparent delay. The phase of the HP and LP should match at the crossover. With a normal IIR crossover which is phase-aligned at the crossover, the bass will always arrive late. If you time align the LF and HF as is suggested (above), here there will be lumps and bumps through the crossover region. It is the result of cancellation caused by the LF and HF phases not matching at the crossover frequency. If you want a flat phase response and no “lumps and bumps” you need to use an FIR crossover. The cost is time, and the time needed is proportional the crossover frequency; the lower the frequency the greater the time required. It’s not a processing speed issue; it’s just the laws of physics. This paper may be of interest. [URL]http://dolby.invisionzone.com/index.php?app=core&module=attach&section=attach&attach_id=7[/URL] [/QUOTE]

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