Sorry, I abxed Atem-lied 9/10 using v0.1.6 -s.BTW this does not mean this version is worse than the last one. I use my very open Alessandro MS-2 when my wife is not around, otherwise I use my canal phones ultimate ears super.fi 5 pro. They are both very good but sound very differently. But even with same hedphones I'm sure there are differences for me from day to day in being able to hear such subtle problems.Just for comparison and to exclude the possibility that something may be slightly wrong with the Delphi implementation: is there a chance to get a analogue MATLAB generated version of Atem-lied?
I also see it as an option to ignore Atem-lied some day especially as the problem is extremely subtle (to me).At the moment however there may be a small chance that the problem is due to a Delphi implementation error and we shouldn't give away the chance to find it.Is the method of the current Delphi version when not using skewing identical to that of the Matlab script? Then it makes sense to try the Matlab version.I hope I have fixed the wavIO problem and will test it tomorrow (I'm too tired now). I'll also try quality -1 tomorrow.
Thanks for the tables.Judging from that I don't think the Atem-lied problem is a problem of the Delphi implementation.In the critical region ~ 6 bits are removed (with both the Delphi and the Matlab version), and I think this is really not appropriate in this situation.So I think we have two choices:1) try more variants, for instance averaging over 3 pins instead of 4.2) if things don't essentially improve accept that Atem-lied is a (very minor) problem sample we get fully transparent only with best quality setting (will try it tonight if the current best quality setting does it).In this case however more listening experience than just mine is most welcome (not only true in this case).
 It was the <censored> random number generator - at least indirectly. In a discussion in another thread it was intimated that one way to carry out triangular dither is to generate one random number per cycle, and subtract the previous random number from the new one.
Don't do that here, at least not yet. It gives you high pass filtered dither noise. There are clear advantages to that, but the threshold calculations assume a flat noise floor.btw, if you were using that, and it was working properly, and atem_lied still sounds bad, then you/we have worse problems than we thought - since the noise was already a few dB lower at the critical frequencies for that sample.Cheers,David.
Something that struck me in looking at the spectrum of Atem_lied is that the lowest bins through the critical section are around 200 Hz, which I don't remember as that common. At those frequencies, averaging over 4 bins might get too much from higher frequencies because each bin covers such a wide range down there. Perhaps averaging fewer bins at lower frequencies might help (a little like the Bark scale).
I didn't really get what the skewing option does. Can you explain it please?I'd really like to see the behavior when averaging over 3 bins. Maybe it's possible to rise the noise threshold this way compensating for the impact of averaging over 3 instead of 4 bins.To me David Bryants idea is plausible, and may be a rough approximation is already valuable like averaging over 4 bins in the frequency range beyond 1.5 kHz and 3 bins below that.IMO it's worth trying.Added:I looked up earlier in this thread where I could not abx a MATLAB Atemlied version based on 3 analyses, noise_threshold_shift=-3, triangular_dither.Where are we with the current Delphi version in terms of these parameters?
A short intermediate result:I abxed the w version 6/6 and ended up 9/10.I abxed the x version 6/6 and ended up 7/10.I don't think w is easier to abx for me. I'm just tired now (especially of listening to Atem-lied), and I think it's better to continue with the remaining versions tomorrow (may be tomorrow morning before going to work if I have sufficient time).Nick, I've emailed you the corrected version of the wavIO unit. Should be ok now.
Skewing now follows a (sin-1) shape rather than (1-cos), now 9dB rather than 6dB;
Perhaps we should split this thread somehow in one that contains bug reports and announcements of versions (which I'm not interested in) and a technical one where strategies and techniques are discussed.Quote from: Nick.C on 21 September, 2007, 07:33:58 AMSkewing now follows a (sin-1) shape rather than (1-cos), now 9dB rather than 6dB;Forgive my ignorance but what exactly is "skewing"?Is there a relation to noise shaping? What's the current state strategy on selecting the 'wasted_bits' count / noise shaping filters (if any) ?Cheers!SG
Bin Freq. 1-sin dB reduction00 0 -1.000 -9.03101 1378 -1.000 -9.03102 2756 -1.000 -9.03103 4134 -0.826 -7.46304 5513 -0.658 -5.94205 6891 -0.500 -4.51506 8269 -0.357 -3.22607 9647 -0.234 -2.11308 11025 -0.134 -1.21009 12403 -0.060 -0.54510 13781 -0.015 -0.13711 15159 0.000 0.00012 16538 0.000 0.000
I tried atem_lied.lossy.z.flac and couldn't abx it (5/10).I also retried atem_lied.lossy.y.flac and didn't arrive at a better result than this morning.
foo_abx v1.2 reportfoobar2000 v0.8.32007/09/21 20:26:28File A: file://C:\150 samples\E12_MODERN_CHAMBER_L_piano_flute.flacFile B: file://C:\150 samples\E12_MODERN_CHAMBER_L_piano_flute.lossy.flac20:26:28 : Test started.20:26:50 : 01/01 50.0%20:26:58 : 01/02 75.0%20:27:01 : 01/03 87.5%20:27:04 : 02/04 68.8%20:27:09 : 03/05 50.0%20:27:16 : 04/06 34.4%20:27:20 : 05/07 22.7%20:27:43 : 06/08 14.5%20:27:49 : 07/09 9.0%20:28:07 : 07/10 17.2%20:28:46 : 08/11 11.3%20:28:59 : 09/12 7.3%20:29:07 : 10/13 4.6%20:29:12 : 11/14 2.9%20:29:54 : 11/15 5.9%20:30:38 : 12/16 3.8%20:30:44 : Test finished. ---------- Total: 12/16 (3.8%)