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PK Error Metric discussion and beta-test

Blumlein 88

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This is a good example of how Deltawave can be thrown off a bit. In the difference file you hear a fair amount of the music and some of the pink noise. D-wave has slightly shifted by a small fraction of a sample. When the files actually aren't shifted at all.

If you go to Manual processing and change offset to zero, then you get a 76.87 db RMS null (81.340 a-wtd) and a Pk Metric of -81.9 db. The difference file consists of only hiss. I haven't tried it, but other than the very first or last second of the file I bet you would have more trouble hearing that.
 

mehmethand

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My workflow is like this:
I'm loading these 2 files into Deltawave as referance and comparison files
I'm pressing match button, Deltawaves analysis the files
I'm checking PK Value.
I m making a blind test between these 2 files using Deltawave comparator.
 
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pkane

pkane

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This is a good example of how Deltawave can be thrown off a bit. In the difference file you hear a fair amount of the music and some of the pink noise. D-wave has slightly shifted by a small fraction of a sample. When the files actually aren't shifted at all.

If you go to Manual processing and change offset to zero, then you get a 76.87 db RMS null (81.340 a-wtd) and a Pk Metric of -81.9 db. The difference file consists of only hiss. I haven't tried it, but other than the very first or last second of the file I bet you would have more trouble hearing that.

Right. DW usually needs at least 30 seconds to a minute of a track. 14 seconds doesn't give it enough to work with.
 
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pkane

pkane

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My workflow is like this:
I'm loading these 2 files into Deltawave as referance and comparison files
I'm pressing match button, Deltawaves analysis the files
I'm checking PK Value.
I m making a blind test between these 2 files using Deltawave comparator.

That's the right workflow. There's nothing but noise in the difference file, and, as you said, the noise is at -65dB. There is an issue at beginning and the end of the tracks. PK Error metric shows it as well, rising to around -72dBFS at the start and the end. It stays below -84dBFS for the rest of the track. PK Error is computed as an average loudness for a sliding 400ms window. If there is a sharp burst of noise or other difference that falls off by 400ms, these will get averaged out by PK Metric, but may still be audible. Here's what the leading edge error looks like, with the peak well above -50dBFS:

1616209083508.png
 

Blumlein 88

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It is the noise and only noise at the beginning making the most difference. If you chop the first 1.3 seconds from each file then you get -76.86 db for the RMS difference and - 82.8 db for Pk metric. When you play the difference file then you hear noise only with no music.
 
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