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Arpiben

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  1. @pkane2001 Hi Paul, I had been comparing DW's spectra (different windows and FFT sizes) with the ones provided by another software Sonic Visualiser: https://www.sonicvisualiser.org/download.html (full free). I may be wrong but I am fearing that DW is not properly applying the windows/settings chosen in Spectrum parameters. The anomalies I previously pointed out regarding increasing noise with frequency are normal, they may be emphasised by how one draw the lines in between each FFT bins ( Line/Step/Block/etc...). Here the same 100 Hz file with a Blackman Harris 4 term: I still hope that you can manage to add a 7 term Blackman-Harris window in order to have a quite clean -200 dB noise floor when requested. Rgds.
  2. 😊 Paul, using the full rights you would have seen something like the above for the 32 bits version used in DW print screens: (I will later verify your 24 bit) 1. No average / No Peak mode: 2. Averaged spectrum: You will notice that we don't have here apparent amplitude artefacts increasing with frequency. With DW the amplitude is around 5-6dB close to Nyquist.. Rgds.
  3. Hi Paul, Yes we do have the choice to select the optimisation goal but we can not force optimisation to act only with a single variable parameter: offset only, drift only, Dc only....Keep in mind that I was looking at pure tones drifts and phase offsets which are not standard files vs audio ones.Therefore I am not complaining about how optimisation actually works. The wave-forms were not captured but generated either by Audacity and saved in 32.bits floating wav or software (Scipy/Mathlab). Generating a pure 100 Hz in Audacity ( amp=0.5 /100 kSps) is enough to show the spectrum averaging anomalies. I checked the same above files with MusicScope. You may use the free trial version limited to 30 seconds: https://www.xivero.com/musicscope/. The free version will not give you access to the UHR spectrum ( FFT= 65536 / 0.67Hz/Bin) but you are not losing so much. In principle, for spectrum they use Blackman Harris 7 term FFT windows. With DW I tried different FFT sizes for spectrum with more or less same anomalies in averaged mode. I am expecting something flat with a noise floor level depending on window applied. Well I do know that we are looking at the limits but I have the feeling that DeltaWave can perform even better 😊
  4. Thanks. Since I am using both Finisar 10 Gbps SMF & MMF SFPs I had a look at their electrical specs to find out that they are almost identical. At the end no idea if one type is more or less noisy. 😉 In principle in Telecom applications we don't care so much about it but let me ask some colleagues from optoelectronics or submarine optical networks if they have more clues than us.
  5. Hi @jabbr Sorry but I am not fully understanding. As far as I know: MMF SFP transceivers are using VCSEL lasers SMF SFP transceivers are using DFB or Fabry-Perot lasers. Therefore I am expecting Multimode SFP electronics to cause less EMI from the destination. You are expecting the opposite. Sincerely I have no clue and would appreciate if you can elaborate. Rgds. MMF: Multi Mode Fibers SMF: Single Mode Fibers
  6. @pkane2001 Hi Paul, Please do you mind helping with the following questions ? Print screens joined are dealing with 10 Hz/100 Hz pure tones sampled @10 kHz (3 million samples). 1 Manual Corrections: I started using it since I was not satisfied with the automatic matching. Great feature indeed since I managed to correct phase offsets and drifts. Is it possible to customise the optimise feature? I mean a dichotomy for example, for the chosen parameter: Offset alone, Drift alone, etc. In my test cases the optimisation didn't work since it was acting at both offset and drift when it should not. BTW correcting phase using zooming in original and matched waveforms is quite painful especially for tiny values where time scale is lost. 😉 2. Default Parameters: How to retrieve default parameters in Deltawave setup? 3. Spectrum artefacts: In average mode there are artefacts increasing with frequency ? How can you explain it? With other audio spectrum software I can manage clean averaged -200 dB floor with 32 bits files, most probably due to better windowing. The issue is that those artefacts are spoiling the phase and jitter accuracy results. 4. 360° Phase jumps : Is there a way to correct such 'fake' phase jumps? Purpose is same as above. Thanks.
  7. According to IEEE 802.3-2018 10 GBASE-SW/SR & 10 GBASE - LW/LR do share same transmitter eye mask definitions.
  8. What about Short Range 10 Gbps ones -> 400m ( 850nm/ IEEE 802.3-2012 10GBASE-SR/SW3) ? Let me have a look at IEE 802.3 Jitter requirements by curiosity 😉
  9. @Em2016 You may have a look at the following paper for a global approach of Jitter in general. https://www.keysight.com/upload/cmc_upload/All/Clock_Jitter_Analysis_2008.pdf. The document is not recent but provides a good overview. From eye patterns you retrieve all relevant information. Nevertheless, there are several ways to look at or measure noise in time or frequency domain. Usually involved test equipment are: phase meters, spectrum analysers, real time scopes (Time Interval Error TIE +Digital Signal Processing), clock references (Rubidium,GPS), etc... Unfortunately, when dealing with noise proof of concepts or comparisons (SFPs, crystals, clocks,etc...) there is no other way than providing proper measurements with significant differences. Obviously above testing equipment are rather expensive (>100 kEuros/ kUSD each) and require expertise. I am not expecting any audio companies to have the required instruments in their labs. Keep in mind also that those publishing specifications are doing it: - in controlled environment ( best possible conditions) - in comparison with information provided by competitors. (Certifications are performed by independent labs ) Nothing is perfect. C'est la vie... Rgds.
  10. @pkane2001 Paul, no need to waste your time with previous errors. Despite the fact that curves were properly presented ( with my files ) in releases 1.033 & 1.034, errors were already there. At the end, no need to worry about and 1.035 have no regression at this level. Rgds. Log with DW v1.033: 2019-07-12 19:13:33.9923|DEBUG|Wave.WaveForm|Settings: Gain:True, Remove DC:True Non-linear Gain EQ:False Non-linear Phase EQ: True EQ FFT Size:524288, EQ Frequency Cut: 0Hz - 384000Hz, EQ Threshold: -300dB Correct Drift:True, Precision:30 Non-Linear drift Correction:False Upsample:False, Window:Hann Spectrum Window:BlackmanHarris, Spectrum Size:65536 Spectrogram Window:Lanczos, Spectrogram Size:32768, Spectrogram Steps:1024 Dither:False Trim Silence:True 2019-07-12 19:13:34.0334|INFO|Wave.WaveForm|Discarding Reference: Start=0s, End=10s 2019-07-12 19:13:34.0485|INFO|Wave.WaveForm|Discarding Comparison: Start=0s, End=10s 2019-07-12 19:13:34.1206|INFO|Wave.WaveForm| Initial peak values Reference: 0dB Comparison: 0dB 2019-07-12 19:13:34.1367|INFO|Wave.WaveForm|Initial RMS values Reference: -3,01dB Comparison: -3,01dB 2019-07-12 19:13:34.1517|INFO|Wave.WaveForm|Null Depth=44,048dB 2019-07-12 19:13:34.1598|DEBUG|Wave.WaveForm|Progress Updating Charts, , 20% 2019-07-12 19:17:27.6192|INFO|Wave.WaveForm|FitPhaseCurve error (rms): linear=9,37757332651059E+151deg 2019-07-12 19:17:27.6348|ERROR|Wave.WaveForm|FitPhaseCurve error too large: linear=1,63669530394807E+150 2019-07-12 19:17:27.6348|ERROR|Wave.WaveForm|ApplyFreqCalibrationComplex: FitPhaseCurve failed 2019-07-12 19:17:27.6348|DEBUG|Wave.WaveForm|Progress Computing results, , 82% 2019-07-12 19:17:27.6348|INFO|Wave.WaveForm| Trimmed 0 samples ( 0,00ms) front, 0 samples ( 0,00ms end) 2019-07-12 19:17:27.7130|DEBUG|Wave.WaveForm|Progress Computing results, , 85% 2019-07-12 19:17:27.8867|DEBUG|Wave.WaveForm|Progress Computing results, , 87% 2019-07-12 19:17:27.9007|DEBUG|Wave.WaveForm|Progress Computing results, , 90% 2019-07-12 19:17:27.9428|INFO|Wave.WaveForm|Gain matching disabled. Phase offset=0ms (0 samples) Difference (rms) = -176,3dB [-178,69dBA] Correlated Null Depth=44,05dB [210,22dBA] Clock drift: 0 ppm 2019-07-12 19:17:27.9428|INFO|Wave.WaveForm| 2019-07-12 19:17:27.9428|INFO|Wave.WaveForm|Files are NOT a bit-perfect match (match=100%) at 16 bits 2019-07-12 19:17:27.9428|INFO|Wave.WaveForm|Files are NOT a bit-perfect match (match=83,74%) at 32 bits 2019-07-12 19:17:27.9639|INFO|Wave.WaveForm|Files match @ 100% when reduced to 12,5 bits 2019-07-12 19:17:27.9639|INFO|Wave.WaveForm| 2019-07-12 19:17:27.9719|DEBUG|Wave.WaveForm|Progress Updating charts, , 91% 2019-07-12 19:17:28.1744|INFO|Wave.WaveForm|---- Phase difference (full bandwidth): 1,80098071837204E-05° 2019-07-12 19:17:28.2125|INFO|Wave.WaveForm| 0-10kHz: 0,00° 2019-07-12 19:17:28.2456|INFO|Wave.WaveForm| 0-20kHz: 0,00° 2019-07-12 19:17:28.2787|INFO|Wave.WaveForm| 0-24kHz: 0,00° 2019-07-12 19:17:28.2837|INFO|Wave.WaveForm|Phase EQ not computed 2019-07-12 19:17:28.3579|INFO|Wave.WaveForm|Timing error (rms jitter): 0sec 2019-07-12 19:17:28.3660|DEBUG|Wave.WaveForm|Progress Updating charts, , 94% 2019-07-12 19:17:28.3770|DEBUG|Wave.WaveForm|Progress Updating charts, , 96% 2019-07-12 19:17:28.3770|DEBUG|Wave.WaveForm|Progress Updating charts, , 98% 2019-07-12 19:17:28.4332|INFO|Wave.WaveForm| RMS of the difference of spectra: -229,851134440609dB 2019-07-12 19:17:41.4353|INFO|Wave.WaveForm|gn=1, dc=0, dr=0, of=0 2019-07-12 19:17:41.4493|INFO|Wave.WaveForm|DONE! 2019-07-12 19:17:41.4574|DEBUG|Wave.WaveForm|Progress [NOT Bit Perfect ] 83,74% Gain matching disabled. Phase offset=0ms Difference (rms) = -176,3dB [-178,69dBA] Correlated Null Depth=44,05dB [210,22dBA] Clock drift: 0 ppm, , 100% 2019-07-12 19:17:41.4574|INFO|Wave.WaveForm|Signature: 1ab5be21ec3cec9510f3874762dd16d0
  11. Hi Paul, Just notice that in the working case my pasted text was incomplete, sorry. Here is the complete one: Nothing to complain about the phase estimation. 😊 Rgds. 1.035b with Phase EQ Disabled: Performing raw processing only -- all matching turned off DeltaWave v1.0.35, 2019-07-12T17:25:43.7253820+02:00 Reference: A.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Comparison: B.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Settings: Gain:True, Remove DC:True Non-linear Gain EQ:False Non-linear Phase EQ: False EQ FFT Size:4096, EQ Frequency Cut: 0Hz - 384000Hz, EQ Threshold: -300dB Correct Drift:True, Precision:30 Non-Linear drift Correction:False Upsample:False, Window:Hann Spectrum Window:BlackmanHarris, Spectrum Size:16384 Spectrogram Window:Lanczos, Spectrogram Size:32768, Spectrogram Steps:1024 Dither:False Trim Silence:True Discarding Reference: Start=0s, End=10s Discarding Comparison: Start=0s, End=10s Initial peak values Reference: 0dB Comparison: 0dB Initial RMS values Reference: -3,01dB Comparison: -3,01dB Null Depth=44,048dB Trimmed 0 samples ( 0,00ms) front, 0 samples ( 0,00ms end) Gain matching disabled. Phase offset=0ms (0 samples) Difference (rms) = -176,3dB [-178,69dBA] Correlated Null Depth=44,05dB [210,13dBA] Clock drift: 0 ppm Files are NOT a bit-perfect match (match=100%) at 16 bits Files are NOT a bit-perfect match (match=83,74%) at 32 bits Files match @ 100% when reduced to 12,5 bits ---- Phase difference (full bandwidth): 4,33363026596958E-05° 0-10kHz: 0,00° 0-20kHz: 0,00° 0-24kHz: 0,00° Timing error (rms jitter): 0sec RMS of the difference of spectra: -217,121670899852dB gn=1, dc=0, dr=0, of=0 DONE! Signature: ab0aff5adad46408e9b5bdb788e5289a
  12. Troubleshooting: 1.035b with Phase EQ Enabled: (same behaviour for smaller FFT sizes 4096 for instance) Performing raw processing only -- all matching turned off DeltaWave v1.0.35, 2019-07-12T15:11:33.1914654+02:00 Reference: A.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Comparison: B.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Settings: Gain:True, Remove DC:True Non-linear Gain EQ:False Non-linear Phase EQ: True EQ FFT Size:524288, EQ Frequency Cut: 0Hz - 384000Hz, EQ Threshold: -300dB Correct Drift:True, Precision:30 Non-Linear drift Correction:False Upsample:False, Window:Hann Spectrum Window:BlackmanHarris, Spectrum Size:16384 Spectrogram Window:Lanczos, Spectrogram Size:32768, Spectrogram Steps:1024 Dither:False Trim Silence:True Discarding Reference: Start=0s, End=10s Discarding Comparison: Start=0s, End=10s Initial peak values Reference: 0dB Comparison: 0dB Initial RMS values Reference: -3,01dB Comparison: -3,01dB Null Depth=44,048dB Stopped! Index was outside the bounds of the array. Signature: 927dc3938d8b2ef0ffa840afa1c6ab02 1.035b with Phase EQ Disabled: Performing raw processing only -- all matching turned off DeltaWave v1.0.35, 2019-07-12T15:25:54.7967053+02:00 Reference: A.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Comparison: B.wav[L] 106496 samples 3000Hz 32bits, mono, MD5=00 Settings: Gain:True, Remove DC:True Non-linear Gain EQ:False Non-linear Phase EQ: False EQ FFT Size:524288, EQ Frequency Cut: 0Hz - 384000Hz, EQ Threshold: -300dB Correct Drift:True, Precision:30 Non-Linear drift Correction:False Upsample:False, Window:Hann Spectrum Window:BlackmanHarris, Spectrum Size:16384 Spectrogram Window:Lanczos, Spectrogram Size:32768, Spectrogram Steps:1024 Dither:False Trim Silence:True Discarding Reference: Start=0s, End=10s Discarding Comparison: Start=0s, End=10s Initial peak values Reference: 0dB Comparison: 0dB Initial RMS values Reference: -3,01dB Comparison: -3,01dB Null Depth=44,048dB Trimmed 0 samples ( 0,00ms) front, 0 samples ( 0,00ms end) Gain matching disabled. Phase offset=0ms (0 samples) Difference (rms) = -176,3dB [-178,69dBA] Correlated Null Depth=44,05dB [210,28dBA] Clock drift: 0 ppm Jitter/Wander distinction: Honestly, I don't care about wording distinction, already used with it. The point is without proper filtering, I am afraid that in some cases, one might not be able to correct the phase variations. A few posts back you already pointed out some differences with phase for frequencies above or below 1 kHz. The following picture may be more explicit, just replace the 24 Hour window by a 5 min one ( or typical average audio file length) The test files are based from TIE phase measurement dedicated equipment such as Annue 3500/Oscilloquartz/Symmetricom. Obviously I am realistic and don't expect DW to reach such precision. My point is to compare real clock phase measurements (low and high jitter) with DW. This will only cover the frequency drift/offset correction and not the Phase EQ ( Group Delay from the different transfer functions:filters,etc...) 😉 Rgds.
  13. Hi Paul, I am having some new issues with DW's latest release 1.035b. With Phase EQ enabled and some tests files. SHOW -> Stopped! Index was outside the bounds of the array. at Wave.Analysis.FitPhaseCurve(Double[] x, Double[] y, Complex[] spectrum, Int32 sz, Int32 freq, Double[]& poly) in C:\Users\ypa\Documents\Visual Studio 2015\Projects\Wave\Wave\Analysis.cs:line 0 at Wave.Analysis.ApplyFreqCalibrationComplex(Double[]& LL, Double[]& L1, Int32 freq, Int32 size, Int32 cutoff, Double[]& polynomial, Int32& last_freq, Func`2& func) in C:\Users\ypa\Documents\Visual Studio 2015\Projects\Wave\Wave\Analysis.cs:line 2240 at Wave.WaveForm.ProcessAll(Double[] L, Double[] L1, Int32 freq, Int32 freq1, Int32 freq2, Int32 bits1, Int32 bits2, Boolean bMatch, Boolean bLoadOnly, Boolean bApplyManual, Boolean bUpdateCharts) in C:\Users\ypa\Documents\Visual Studio 2015\Projects\Wave\Wave\WaveForm.cs:line 2416 2019-07-12 00:59:49.0550|INFO|Wave.WaveForm|Stopped! Index was outside the bounds of the array. 2019-07-12 00:59:49.0550|DEBUG|Wave.WaveForm|Progress Stopped!, , 100% The above is not happening with DW R1.034 & same test files.I am interested in the possible reason for such ( not enough samples/etc). Well my files are dealing with real TIE measurements;i.e: very low wander/jitter& drift ( ~1ns/~1ppb/day). I applied the TIE to a single tone and very well know that DW's clock correction doesn't work with such signals. Later I will apply them to other functions and check them with DW. I am only surprised that DW allows MATCH to provide much worst results than original without control or warning. As a side remark: In standards, 10 Hz is the line between Jitter and Wander. A HP filter applied to phase reveals Jitter (Noise) while a LP filter applied to phase reveals wander. Wander or the phase long term variations allow to estimate and correct the clock 'long' term issues ( t>0.1s) Dealing with audio files, I have no idea if the 10 Hz value can be kept for LP=HP frequency cut. If not 100 Hz could be a good candidate. Rgds.
  14. @pkane2001 &/or @fas42 Any link pointing to the original file looped? The one in Gearslutz seems to be broken. Thanks.
  15. Thanks Paul. For my own curiosity, I am trying to know if we can improve the phase estimation using different phase unwrapping methods. But I am only at the beginning with little free time... Rgds.
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