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      02-12-2013, 05:32 PM   #20
kaigoss69
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Drives: '08 335i
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Quote:
Originally Posted by makkan00 View Post
Kaigoss
HU has abilities to tune and equilise the whole system. I read a post by VP electricity where he used RTA and found that underseats were louder when fitted in reverse phase, as they complemented the sound waves of mid better in reverse phase (I guess).
I was going to try it but though to do it with stage 3 upgrade.

To my surprise, this HU has reversed the phase of underseats automatically and that has happened each time I tuned it.
I guess due to being under seats, and playing lower frquencies, sound waves from underseats (in reverse phase) are more in sync with mids and reach to listener at same time as frquencies of mids reaches.

Since sub is fed by the same channel as underseats, it is also reversed.

As my HU allows me to reverse these settings, I have done following further experiments.
Mids: normal phase
Underseats: normal phase (reversed set by HU)
sub: normal phase

There is a delay in mid bass / bass if I do that, more noticeable from the rear sub. To sum up, sound is not coherent.

I have done the same as above but with the sub in reversed phase (from the amp settings). Sounds get terrible. Tansition of sound from underseats to sub is messed up.

I read somewhere that time allignment matters upto 2Khz and after that it become meaningless due to high frequencies. I am not sure how true is that, but it clearly emphasis the importance of time / phase allignment b.w mids, underseats (mid bass) and sub bass.

Hope it answer your question.

Thanks for the info. Interesting that the auto-tune reversed the phase of the midbass/sub channel. I have played a lot with sub to midbass phase, but never with midbass to midrange. I'll have to try that!

I wish the MS-8 had the capability to make those corrections during auto-tuning and would give the user the ability to make them afterwards as well. Same with sub TA. I don't care what anyone says, you can get the sub better integrated with TA. As I have pointed out, MS-8 users are stuck with reversal of speaker lead polarity and crossover slope as the only methods for integrating the sub with the midbass, which is often not enough.
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