Jump to content

Arpiben

Members
  • Content Count

    230
  • Joined

  • Last visited

About Arpiben

  • Rank
    Sophomore Member

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. I am not seeing anymore any curve for Clock Drift but it is maybe me..... Rgds Final peak values Reference: 0dB Comparison: 0,144dB Final RMS values Reference: -3,01dB Comparison: -3,011dB Gain= 0dB (1x) DC=0 Phase offset=-0,014423ms (-0,923 samples) Difference (rms) = -48,65dB [-49,4dBA] Correlated Null Depth=89,23dB [86,31dBA] Clock drift: 0,35 ppm Files are NOT a bit-perfect match (match=1,65%) at 16 bits Files are NOT a bit-perfect match (match=0%) at 32 bits Files match @ 49,9958% when reduced to 7,59 bits ---- Phase difference (full bandwidth): 301,35525199606° 0-10kHz: 18,11° 0-20kHz: 250,05° 0-24kHz: 273,80° ---- Variable Group Delay. Frequency matched from 0Hz to 20,0kHz: 1kHz = 4,8μs (1,71°) 2kHz = 1,1μs (0,77°) 4kHz = 201,9ns (0,29°) 8kHz = 536,4ns (1,54°) 16kHz = 626,8ns (3,61°) Timing error (rms jitter): 8,7sec RMS of the difference of spectra: -307,944098772555dB gn=1,00000055023175, dc=0, dr=3,45958E-07, of=-0,923065564 ---Measurements (for a simple sine-wave only)--- Comparison DR = 142,53dB Comparison THD+N = -7,42dB Comparison THD = -161,95dB H1 (1000Hz) = 0dB H2 (2000Hz) = -160,71dB H3 (3000Hz) = -165,61dB H4 (4000Hz) = -168,54dB H5 (5000Hz) = -170,79dB H6 (6000Hz) = -172,41dB H7 (7000Hz) = -173,66dB H8 (8000Hz) = -174,89dB H9 (9000Hz) = -175,96dB H10 (10000Hz) = -176,72dB DONE! Signature: 5d2847516850f38b5b7f631ab6b32783
  2. Hi Paul, I am ok with the corrections brought by the new release but I still have some pending questions if you allow 😉: 1° Clock driftt curve seem to have disappeared. 2° Dealing with integer offset sample values lead to correct/accurate result only if phase drift is unselected. Otherwise we are getting wrong offset/drift values. 3° Dealing with subsample offset values can you tell what is the expected resolution? For point 2° I understand it all depends on the strategy adopted for the correction but I am a bit disappointed we can not detect such cases even with audio files versus simple waves. For point 3°, in case of subsample offsets I would like to know what is the expected resolution. In principle it should depend if you are using or not interpolation and so on... Thanks a lot Paul. Tests have been performed with a 1kHz pure sine with a fixed timed offset: y = sin(2*pi*f0*(t+/-TIE) f0=1kHz / fs=64kHz / TIE= k/fs or 1/(k*fs)
  3. Great Paul! Take your time there are no blocking points 😉, therefore no need for a pre release. I will patiently wait. Thanks.
  4. Hi Paul, Summarizing it DW v1.0.46b introduces a gain factor of 4 for comparison file during Matching as soon as Correct Phase Drift is selected. This behaviour was not encountered in previous releases. Rgds.
  5. Hi @pkane2001 In case it helps the gain=4 applied to Comparison is also present with whatever audio files/FFT length/window provided that: Correct Phase Drift + Measure Simple Waveform + NO Match Gain are enabled. Rgds N.B. if Match Gain is enabled then Comparison will have a correction of something like gn = 0.25*****.
  6. Hi Paul, It is happening with whatever window at least with joined files: no resampling and 64kHz rate as previously mentioned. It is happening only with simple waveform mode and phase drift correction as soon as you press match. Rgds. A.wav B.wav
  7. Completing your reference some measurements. Not all batteries are equal vs noise... http://www.hoffmann-hochfrequenz.de/downloads/NoiseMeasurementsOnChemicalBatteries.pdf
  8. Hi @pkane2001 The phase drift correction is having some issues with simple waveforms at least. 1° There is a gain value of 4 applied to comparison once drift is selected. In order to get the proper estimation one must select Match Gain. I am suspecting there is an upsampling gain not corrected/taken into account. 2° Dealing with integer offset sample values lead to correct/accurate result only if phase drift is unselected. Otherwise we are getting wrong offset/drift values. 3° Dealing with subsample offset values can you tell what is the expected resolution? Tests have been performed with a 1kHz pure sine with a fixed timed offset: y = sin(2*pi*f0*(t+/-TIE) f0=1kHz / fs=64kHz / TIE= k/fs or 1/(k*fs) Rgds
  9. Hi TomCapraro, Is your file a chirp ? Samplers improved a lot in DW but if one wants some more extra dB you may build and apply your own ones. 😉 Rgds.
  10. Yes you did and I am very grateful for it. The point is that for fun and learning purposes I wanted to retrieve the exact frequencies and phases. Now one can generate its own multitone ... Rgds.
  11. Here are the frequencies used by AP's 32 tones test (192 kHz sampling/FFT 65536). IMHO, the distribution is not so obvious .😉 Rgds.
  12. Hi Paul, But at least you got the frequencies right , not yet my case. AP's frequencies aren't equally spaced.😉
  13. Yes from my point of view, but I am not THD expert. It seems that algorithm calculates the difference between Ref&Comp harmonic at first glance. But there is probably some power density calculation within a specified bandwidth which might be tricked...No idea. Paul will help us 😉
  14. Now we are phase aligned 😊. I am getting your results. Comparison THD = -26,07dB H1 (1000Hz) = -1,78dB H3 (3000Hz) = -102,16dB H5 (5000Hz) = -70,5dB H7 (7000Hz) = -94,43dB
  15. Hi Paul, I have been generating ( for fun and learning purposes) multi tones with low crest factor ( Golay_Rudin_Shapiro, Newman, Schroeder, Kitayoshi, etc...). The point is I didn't succeed yet retrieving the algorithm for matching the frequencies of AP file. In principle, it should not be so difficult but I am struggling... Do you mind sharing how did you generate them? Here are some phases : Newman: Schroeder: Kitayoshi:
×
×
  • Create New...