Disturbing time alignment results

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UliBru
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Re: Disturbing time alignment results

Post by UliBru » 16 Nov 2020 20:29

Be aware that the real sub will show up a roll-on in the frequency response. It does not transfer down to DC. Thus its pulse response looks different to the XO low pass.
Stay well tuned
Uli

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Acourate system: JRiver/Roon -> AcourateConvolver -> miniDSP U-DIO8 -> TacT M/S2150 amps -> DIY horn speakers
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 16 Nov 2020 20:37

The blue curve is the real subwoofer. Same graf as in the first post overlayd with the XO pulse. As I wrote I have rotated it in place and added some gain.
Best regards. Bengt
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 16 Nov 2020 23:16

And here I did the same to the midbass xo, there are six midbass drivers. That might have an affect, I guess. But the EQ'd xo file is clearly recognized anyway. Whats a bit interessting is that the pulse going down is almost the same in amplitude as the positve one and when the pulse passes the 0 level in the new corrected filter I havent tried yet, it says (in that point) that the difference is ~7cm on the "right side" of the tweeter :? I'm probably way of but I saw it anyway.

Image
Best regards. Bengt
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 16 Nov 2020 23:31

And there are tweeters as well, no EQ there.

Image
Best regards. Bengt
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UliBru
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Re: Disturbing time alignment results

Post by UliBru » 17 Nov 2020 10:25

Bength,

can you send me some measurements by PM?
I would like to get measured pulse responses all with the same fullrange sweep signal but with applied XO, zero rotation, for:
- tweeter
- tweeter + midrange
- tweeter + bass
- tweeter + midrange + bass

So you can simply run the sweeps and switch off/on the amplifier for bass + midrange.
Stay well tuned
Uli

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Acourate system: JRiver/Roon -> AcourateConvolver -> miniDSP U-DIO8 -> TacT M/S2150 amps -> DIY horn speakers
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 17 Nov 2020 10:58

That can be done but it may take some time since my wife is working from home and is in phone/web meetings most of the day. How about if I compensate for latency introduced by the EQ functions, would that be ok. That I already have stored and wouldn't have to change them back again.
Best regards. Bengt
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UliBru
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Re: Disturbing time alignment results

Post by UliBru » 17 Nov 2020 11:33

If possible send me the pulses I've asked for. Take your time.
Stay well tuned
Uli

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Acourate system: JRiver/Roon -> AcourateConvolver -> miniDSP U-DIO8 -> TacT M/S2150 amps -> DIY horn speakers
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 17 Nov 2020 12:12

I actually had the original xo stored :) No measurements yet though.
This is the delay created by the eq function I'm writing about:

Image

Eq'd filter looks like this:

Image
Best regards. Bengt
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UliBru
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Re: Disturbing time alignment results

Post by UliBru » 17 Nov 2020 13:26

If you have prepared the XO filter with EQ you can send me them too.
And then the measurements as described above with these XOs applied.
Stay well tuned
Uli

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Acourate system: JRiver/Roon -> AcourateConvolver -> miniDSP U-DIO8 -> TacT M/S2150 amps -> DIY horn speakers
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Dahlberg
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Re: Disturbing time alignment results

Post by Dahlberg » 17 Nov 2020 13:33

Yes of course :)
I made a measurement of the, -400 for sub, tweeter in the middle, and +40 samples for midbass approach.
Came up like this:

Image

Not what I was aiming for.
Best regards. Bengt
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