07-27-2022, 03:54 PM | #15 |
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Those delay values appear to be due to acoustic alignment with the sub. Do you have a bandpass on the sub or just lowpass? I typically see higher overall mb-mid-tw delays when the sub is low pass only due to phase rotation at the crossover. Adding a subsonic filter can bring the sub forward in time so the delays aren't as high.
This only tends to affect noise cancellation systems during calls, where the delays push the signal out of the BT echo cancellation timeframe.
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07-27-2022, 03:56 PM | #16 |
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Please do post! I took a look at your build log and your build is amazing. Almost went with the same AF mids and tweets you have (and the stealthbox, which I had briefly before deciding to go vert). I do a really bad job of logging and taking pics (always rushing due to my toddler)
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07-27-2022, 04:06 PM | #17 | |
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Quote:
The SB 2.5’s have a nice, flat, clean response and they actually fit in the stock location. I wish they had a bit more sensitivity, but that’s it. Also considered AF GS/GB25 and Morel CCWR254’s but these are substantially cheaper than both, offer similar linear excursion as the AF’s, and are more detailed than both. My fav tweet (especially for a two way) is the SB Acosutics SB29BAC, but it’s a bit too big to fit in the a pillar firing off-axis as I have mine. The Scans look better and perform just as well for my application (>3500hz), so I opted for them. Also got both the midbass and tweets discounted, about 15% off. |
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07-27-2022, 04:14 PM | #18 | |
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All of this was a bit of a surprise since all my crossovers are LR4, so electrically there should be phase coherence—but clearly it isn’t the case acoustically! |
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07-28-2022, 07:41 AM | #19 | |
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That's better, because I didn't think the VXi DSP had phase rotation since it uses IIR filters, but your delays made me wonder if that was the case. Even with 24db LR filters (HPF have positive phase shifts, LPF have negative phase shifts, 45 deg of rotation for each 6dB/oct slope = 180deg at 24dB/oct - and if both drivers are 180 deg then they re-align in phase but a full cycle off in time). There is still phase rotation with some topologies - and while it's predictable with passives or op-amps, it's harder to know what exactly the active filter is doing when it's all DSP. This article does a good job explaining it: https://www.ranecommercial.com/legacy/note160.html. I didn't notice the polarity flip. That makes sense given the other info.
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Historically an Accord and Camry owner with self-performed maintenance/repair. 1100: 5/3/22 . . . . . . . 2000: 6/25/22 . . . . . .4000: 8/17/22 . . . . . . . 6000: 9/10/22 Daily Driver mileage update: 22k mi. @ April 2024 New Engine @ 22,600 Build Log: https://www.camaro6.com/forums/showt...6#post11353116 |
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07-28-2022, 12:51 PM | #20 | |
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07-30-2022, 09:23 PM | #21 | |
Drives: '17 M6 2SS Vert Hyper Blue/Kalahari Join Date: May 2022
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