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<blockquote data-quote="Bennett Prescott" data-source="post: 117737" data-attributes="member: 4">Re: Measurement QuestionHey Brent,Nice messy measurement, always challenging when you&#039;re looking at graphs like these.Looks to me like the LF is out of phase by 120° or so when the HF polarity is &quot;correct&quot;. Probably the two speakers have very different phase slopes, or perhaps just as a result of your HPF on the fills. You could confirm with a nearer measurement that had better signal to noise. IMHO, the phase/polarity of the HF is unimportant compared to lower frequencies. If the HF is all hashed up then you will have very localized interference that your ears will largely ignore, as usually each ear will be in a different acoustic environment. Mess up 400Hz though and the response nulls and peaks will be much physically larger, if I had to pick I would go for good alignment across a wider area in the mid frequencies and let the above 8kHz stuff slip out of alignment.Your real problem is likely the different slopes of the phase trace in each speaker system. Can you find some way to make them closer? This is one reason it&#039;s nice to have fills built with good hardware, as there are a few tricks I can pull to get them to match the phase of the mains. I always prefer to make compromises in the fills rather than add phase rotations to the mains. The more the two traces differ the narrower a bandwidth you&#039;re going to have to hit with your alignment.</blockquote>

[QUOTE="Bennett Prescott, post: 117737, member: 4"] Re: Measurement Question Hey Brent, Nice messy measurement, always challenging when you're looking at graphs like these. Looks to me like the LF is out of phase by 120° or so when the HF polarity is "correct". Probably the two speakers have very different phase slopes, or perhaps just as a result of your HPF on the fills. You could confirm with a nearer measurement that had better signal to noise. IMHO, the phase/polarity of the HF is unimportant compared to lower frequencies. If the HF is all hashed up then you will have very localized interference that your ears will largely ignore, as usually each ear will be in a different acoustic environment. Mess up 400Hz though and the response nulls and peaks will be much physically larger, if I had to pick I would go for good alignment across a wider area in the mid frequencies and let the above 8kHz stuff slip out of alignment. Your real problem is likely the different slopes of the phase trace in each speaker system. Can you find some way to make them closer? This is one reason it's nice to have fills built with good hardware, as there are a few tricks I can pull to get them to match the phase of the mains. I always prefer to make compromises in the fills rather than add phase rotations to the mains. The more the two traces differ the narrower a bandwidth you're going to have to hit with your alignment. [/QUOTE]

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