TomCapraro Posted October 19, 2019 Share Posted October 19, 2019 4 minutes ago, pkane2001 said: Then I withdraw my comment! We will investigate but, I have the impression that as I said before, every ADC "likes" a certain type of signal to be able to align itself very well ... they too have their own tastes ... !!!😂 Link to comment
TomCapraro Posted October 19, 2019 Share Posted October 19, 2019 1 hour ago, esldude said: That is odd. I get better results with the signal I posted than yours. And yours is just the reverse. With the modulated white noise I get 15 db poorer difference results and 12 db poorer correlated null results. This is with measure simple waveforms checked. With Measure simple waveforms unchecked. My results on the modulated white noise deteriorate another 7 db, while with the signal I posted it improves an additional 10 db. Makes me think neither signal is a good signal for general checking of how an ADC/DAC loop is performing. How did you set the FFT window? This only works if you use the Dirichlet If you didn't, copy the settings and try again with my pseudo-random white noise Link to comment
esldude Posted October 19, 2019 Share Posted October 19, 2019 23 minutes ago, TomCapraro said: Can you please post the wav delta file that I overlay with mine? Probably there will be some signal even more suitable, but 19ps of RMS jitter and the difference spectrum so low from me produces results in line with the non-linear alterations of the dac I'll do that later when I get back home. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
esldude Posted October 20, 2019 Share Posted October 20, 2019 Is this what you want, anything else that would help. Same overlay only reversed so you can see results for both files in the lower pane of the window. Settings were the same for both. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
esldude Posted October 20, 2019 Share Posted October 20, 2019 With the same exact settings. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
pkane2001 Posted October 20, 2019 Author Share Posted October 20, 2019 24 minutes ago, esldude said: Is this what you want, anything else that would help. Same overlay only reversed so you can see results for both files in the lower pane of the window. Settings were the same for both. Not sure if that's the problem here, but remember that Simple Waveforms setting disables drift correction. If there's a clock drift between reference and comparison files, the null will not be as good. -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
esldude Posted October 20, 2019 Share Posted October 20, 2019 1 hour ago, pkane2001 said: Not sure if that's the problem here, but remember that Simple Waveforms setting disables drift correction. If there's a clock drift between reference and comparison files, the null will not be as good. Yes that was my understanding of how it worked. I was just copying Tom's settings. I normally uncheck non-linear drift compensation as I understood no drift compensation happens if Simple is checked. I don't know there is a problem, but it is surprising to me. I didn't realize changing the window for the spectrogram also changed the nulling results. Am I correct about that being how it works. I wasn't surprised settings for phase limit and EQ threshold would change the results. It looks like the best setting for that is going to be down to the individual characteristics of the file. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
pkane2001 Posted October 20, 2019 Author Share Posted October 20, 2019 3 hours ago, esldude said: Yes that was my understanding of how it worked. I was just copying Tom's settings. I normally uncheck non-linear drift compensation as I understood no drift compensation happens if Simple is checked. I don't know there is a problem, but it is surprising to me. I didn't realize changing the window for the spectrogram also changed the nulling results. Am I correct about that being how it works. I wasn't surprised settings for phase limit and EQ threshold would change the results. It looks like the best setting for that is going to be down to the individual characteristics of the file. The nonlinear EQ settings drive these differences, since FFT and complex spectrum are used to compute the differences in amplitude and phase. So yes, window setting will affect this to some degree, as will FFT size and phase limit. -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 497/5000 Paul made an observation that could bring this difference closer.In my loopback circuit (D / A - A / D) there is no clock drift, or if there is it is too small.Activating the sinusoidal correction eliminates the drift clock function but since there is no alteration the result improves.I've tried with other hardware (realtek HD loopback card) and it gives me excellent results.I should see a loopback where there is clock drift.I also thank Esldude for posting the graphs. Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 96/5000 TEST: I took a loopback with clock driftThe result improves with the drift clock activated Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 If active the simple correction the result gets worse but is better than the one with clock drift deactivated Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 And finally the result with all the other corrections activated before with simple signals deactivated and then activated. So even with loopback with clock drift I tend to improve the situation Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 Here a loopback with 7.13ppm of clock drift. By activating the simple correction this time it gets worse but ... in this case a white pseudo-random signal was not used, only random aperiodic pink noise. Link to comment
TomCapraro Posted October 20, 2019 Share Posted October 20, 2019 Sorry if I didn't specify it, even in the previous graphs a random signal (pink noise) was used I should repeat the test with pseudo-random white noise I believe (at least so it seems to me) that the combined rectangular FFT + simple correction provides excellent results Link to comment
pkane2001 Posted October 20, 2019 Author Share Posted October 20, 2019 6 hours ago, TomCapraro said: 497/5000 Paul made an observation that could bring this difference closer.In my loopback circuit (D / A - A / D) there is no clock drift, or if there is it is too small.Activating the sinusoidal correction eliminates the drift clock function but since there is no alteration the result improves.I've tried with other hardware (realtek HD loopback card) and it gives me excellent results.I should see a loopback where there is clock drift.I also thank Esldude for posting the graphs. Thats correct, Tom. Without clock drift, simple waveform setting should work very well. With clock drift, drift correction will be necessary to improve the result. -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
TomCapraro Posted October 25, 2019 Share Posted October 25, 2019 Good evening, I posted an original file (tone 1000hz) and its registration. Notice if the THD values come out correct ... it doesn't seem to me ... orig.wav rec.wav Link to comment
esldude Posted October 25, 2019 Share Posted October 25, 2019 3 hours ago, TomCapraro said: Good evening, I posted an original file (tone 1000hz) and its registration. Notice if the THD values come out correct ... it doesn't seem to me ... orig.wav 7.32 MB · 1 download rec.wav 7.32 MB · 1 download It looks correct to me in the spectrum of delta. It might appear wrong in the delta of spectra, but actually is correct from what I am seeing. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
TomCapraro Posted October 25, 2019 Share Posted October 25, 2019 9 minutes ago, esldude said: It looks correct to me in the spectrum of delta. It might appear wrong in the delta of spectra, but actually is correct from what I am seeing. What values do you get in the results? Link to comment
esldude Posted October 25, 2019 Share Posted October 25, 2019 1 minute ago, TomCapraro said: What values do you get in the results? -27.47 db for difference (which just eyeballing looks right for the 3rd harmonic in the recorded file). And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
TomCapraro Posted October 25, 2019 Share Posted October 25, 2019 3 minutes ago, esldude said: -27.47 db for difference (which just eyeballing looks right for the 3rd harmonic in the recorded file). H3 (3000hz) I get -102dB Link to comment
esldude Posted October 25, 2019 Share Posted October 25, 2019 16 minutes ago, TomCapraro said: So how do you get that display to come up in Deltawave. Must be a key or hidden menu I missed. And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
esldude Posted October 25, 2019 Share Posted October 25, 2019 56 minutes ago, esldude said: So how do you get that display to come up in Deltawave. Must be a key or hidden menu I missed. I am running 1.45 btw. So does that THD display just show up or is there a key control to pull it up on simple waveforms? And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
TomCapraro Posted October 26, 2019 Share Posted October 26, 2019 It is a copy-paste image taken from the results. The DeltaWave version is 1.0.45 esldude 1 Link to comment
Arpiben Posted October 26, 2019 Share Posted October 26, 2019 @TomCapraro Please, can you share your spectrum settings since I am also having correct harmonic levels with Kaiser & Dirichlet? Rgds Link to comment
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