Optimal crossover point for my measurements

2234rew

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This is imo a very fine result. I would have easily lived with this kind of performance.
Thanks for your help in getting to this point.

There's no urgency from my end to solve this low end pre-ringing because I'm loving SQ.

I'll park this aside and focus on the HDMI drama
 

juicehifi

Audiolense
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Quite observant of you, jjazdk, :T

I usually run a «development license» which basically exposes a lot of stuff that has gone out and some stuff that has never gone in .... and some stuff that was only for development purposes.

I can assure you that every parameter where I believe a custom setting could improve the sound quality is exposed to the user.
 

jjazdk

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Aug 17, 2018
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Thanks :-)

I have not given up on Audiolense, and am still toying with the measurements. Downloaded 6.17 yesterday, and succeded in making consistent measurements through JRiver (Direct Sound Out to JRiver, Direct Sound In from my OmniMic USB microphone).
My idea was to experiment with really short TTD (1344 taps = 15ms delay@44k1, to be within the critical lip sync window). But.. The corrections goes totally bogus when I make them with less than 2048 taps :-/




Quite observant of you, jjazdk, :T

I usually run a «development license» which basically exposes a lot of stuff that has gone out and some stuff that has never gone in .... and some stuff that was only for development purposes.

I can assure you that every parameter where I believe a custom setting could improve the sound quality is exposed to the user.
 

hulkss

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Feb 12, 2020
Messages
153
Thanks :-)

My idea was to experiment with really short TTD (1344 taps = 15ms delay@44k1, to be within the critical lip sync window). But.. The corrections goes totally bogus when I make them with less than 2048 taps :-/
Try the Audiolense Convolver. I use 65000 (approx) taps and have only 7 ms latency in the convolver filters. Frequency correction only, minimum phase target, and min delay crossovers if you use them.
 

jjazdk

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Aug 17, 2018
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59
Try the Audiolense Convolver. I use 65000 (approx) taps and have only 7 ms latency in the convolver filters. Frequency correction only, minimum phase target, and min delay crossovers if you use them.
I did try that, and it did not at all work in my system. Mid left+right bass drivers (100-250Hz) ended up not summing at all, while the rest of the frequency spectrum summed nicely.

Also, 1344 taps is enough to account for a lot of phase issues.
 

juicehifi

Audiolense
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TTD doesn't always work well on very short filters. 1344 taps is very scarce to clean up the time domain and then fix the frequency response.
 

jjazdk

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Aug 17, 2018
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TTD doesn't always work well on very short filters. 1344 taps is very scarce to clean up the time domain and then fix the frequency response.
It is, I agree.

But, the correction with 1344 taps really screws up the response in a very mystical way. The frequency response from my nicely corrected (with MSO) subwoofers goes totally haywire. I can make a few plots if it is of interest?
 

juicehifi

Audiolense
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You may find something that works if you apply short TTD window. It has to be well inside the total taps available.
 

jjazdk

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Ahhh, I did not think of that. I will try that and see if the simulation comes up with some sensible results. Thanks.
 

jjazdk

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Aug 17, 2018
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You may find something that works if you apply short TTD window. It has to be well inside the total taps available.
Hmm.. Can you elaborate on this. How do I apply a TTD window that is short enough for a 1344 tap filter at 48000kHz (14ms filter length) ?

Quite often Audiolense comes out with filters that make no sense at all, as in correction filters that allows the subwoofer signal through, but attenuates the front speaker 70dB.

As soon as I go from 1344 to 1536 taps, this strange behaviour dissapears.

Also, even if I closely match the targetcurve to the measured subwoofer response, it still tends to make a really strange filter for the subwoofer channel. Quite odd, as I am trying to make it easy for the filter matching algorithm, hmm..

41636
 

jjazdk

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Aug 17, 2018
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Missing Front Left Speaker?!?

But here the subwoofer filter matches the target response very well.

41637
 

juicehifi

Audiolense
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When you combine crossover and TTD with such a short filter you need some luck to get a good result. It is basically a matter of trial and error.
 

jjazdk

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Aug 17, 2018
Messages
59
When you combine crossover and TTD with such a short filter you need some luck to get a good result. It is basically a matter of trial and error.
Fair enough. But, look at my last screenshot, the correction filter for the Front Left is missing and so is the Front Left output. Only the subwoofer part of the simulated response is there?!?
 

juicehifi

Audiolense
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207
It's down there somewhere. These things can happen when you run out of taps.
 
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