manisandher
Addicted to Fun and Learning
- Thread Starter
- #241
Bollocks. Now the bot is getting Shannon-Nyquist wrong and stirring it into the pot.
Automated Brandolini.
Haha. I'll stop.
Bollocks. Now the bot is getting Shannon-Nyquist wrong and stirring it into the pot.
Automated Brandolini.
Automated Brandolini.
Try it and see. The larger issue with the filter is not that it causes damage below 10Hz, but that it causes phase change over the entire bandwidth.I had a thought in the gym this morning - without ChatGPT.
What if I apply a high-pass filter (6 dB/octave, minimum-phase at ~0.07 Hz) offline to my reference file, to create a new 'compensated reference file', Ref_c. I'll then use Ref_c for the input to the DA/AD chain, and as also as the reference in DeltaWave.
The idea is that in using Ref_c, the RME’s own coupling filter should have little or nothing to do <10Hz.
Thoughts?
Try it and see. The larger issue with the filter is not that it causes damage below 10Hz, but that it causes phase change over the entire bandwidth.
Sorry - lost track of what's you are doing. Perhaps you could have a "what we've learned so far post"?6 dB/octave, minimum-phase at ~0.07 Hz
Then you would be comparing a 2nd order filter (recording of digital first order followed by analog first order) to a1st order filtered reference.I had a thought in the gym this morning - without ChatGPT.
What if I apply a high-pass filter (6 dB/octave, minimum-phase at ~0.07 Hz) offline to my reference file, to create a new 'compensated reference file', Ref_c. I'll then use Ref_c for the input to the DA/AD chain, and as also as the reference in DeltaWave.
The idea is that in using Ref_c, the RME’s own coupling filter should have little or nothing to do <10Hz.
Thoughts?
Then you would be comparing a 2nd order filter (recording of digital first order followed by analog first order) to a1st order filtered reference.
Hmm... I'll give it a go anyway as I'm curious to see what happens.
Mani, you might like this new versionhttps://app.box.com/s/h2u20jzre4bake02n5aj40kc5r2woaa0
Interesting... I used the same 0.01Hz minimum phase filter with my own ADI-2/4 SE Pro capture, and it improved RMS difference from -78dB to -84dB:Thanks Paul, that's phenomenal. Will give it a go shortly.
@pkane for my understanding, it appears you are only applying the HPF to the reference and NOT the recording, is that correct?
Michael
Again, I don't recommend manipulating the reference waveform for any real comparisons/measurements...
Because you don't know the exact amplitude or phase of the ADC filter and you can't measure it directly without other components and filters in the recording path.Paul, if the compensating filter is matched to the ADC's filter (as closely as possible) and then applied to the reference file only, why would this not be a valid way of increasing the sensitivity of the comparisons/measurements?
That can help, but I assume it'll vary with DACs to some degree. ADC filter can vary also between the same model ADC units due to component variations and/or tuning and adjustments.Might a good validity test be that the compensating filter improves the comparisons/measurements for all DACs equally?