Let me add two samples available here. You can hear boosted close hi-hat cymbal in the 8823 sample with 1.0.1 -q4. The second sample is white noise created by CoolEdit. I suppose some of you disagree with the use of artificially created sample, but the problem with 1.0.1 -q4 is too obvious for me. I found the sample encoded by 1.0.1 -q4 totally different from the original. I'm not sure this sample exposes HF boost problem (or another problem?), but I believe it's a good material to improve Vorbis.
Actually, I created my "Modest Tuning" to improve these samples. Here's a part of my personal listening result (in Japanese only) of 8823 sample (I focused on only HF boost) with Modest Tuning beta2 (mtb2), aoTuV alpha2 (at2), GarfTuned3 beta1 (gt), QKTune beta2 (qk2).
ABC/HR Version 0.9b, 30 August 2002
Testname: 8823
1L = C:\users\musics\test\compare\8823-q5qk2.wav (171kbps)
2L = C:\users\musics\test\compare\8823-q5at2.wav (158kbps)
3L = C:\users\musics\test\compare\8823-q5gt.wav (178kbps)
4L = C:\users\musics\test\compare\8823-q4mtb2.wav (169kbps)
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General Comments:
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1L File: C:\users\musics\test\compare\8823-q5qk2.wav
1L Rating: 3.0
1L Comment:
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2L File: C:\users\musics\test\compare\8823-q5at2.wav
2L Rating: 3.5
2L Comment:
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3L File: C:\users\musics\test\compare\8823-q5gt.wav
3L Rating: 2.5
3L Comment:
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4L File: C:\users\musics\test\compare\8823-q4mtb2.wav
4L Rating: 4.5
4L Comment:
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ABX Results:
Original vs C:\users\musics\test\compare\8823-q5qk2.wav
13 out of 14, pval < 0.001
Original vs C:\users\musics\test\compare\8823-q5at2.wav
13 out of 14, pval < 0.001
Original vs C:\users\musics\test\compare\8823-q5gt.wav
13 out of 14, pval < 0.001
Original vs C:\users\musics\test\compare\8823-q4mtb2.wav
12 out of 21, pval = 0.332
I haven't test these samples with uncoupled stereo but I'll later.