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Suggest ~160kbps VBR setting.
guidryp
post Mar 30 2002, 19:27
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Hi,

Looking at the suggested settings/presets I am dismayed at the lack of a VBR setting that operates at a lower bit-rate.

There is APS standard, which on my music easily averages over 200Kbps. In fact my latest Rush albums are averaging over 220Kbps.

I can see noisy metal taking over 220kbps, but a song like Rush-Nobody's Hero taking 230Kbps?

For me, it calls into question the validity of the VBR model if the answer to lower than 230KBps encoding is to use the ABR/CBR settings.

ABR doesn't seem much better than CBR after watching it encode 90+ % of its samples at the target rate.

Surely a VBR setting can be cooked up that can encode the above track at ~160kbps in VBR and still sound better than 160 ABR.

PS - I want to use this setting in my compact Flash based portable, in my car etc. My max space average is 160Kbps do to the size of the portable memory. But I want the best quality in that space.

Peter
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guidryp
post Apr 2 2002, 15:02
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QUOTE
Originally posted by JohnV
Seems that you didn't understand the SFB21 problem with vbr I was trying to explain. If you use only --lowpass 16, the lower frequencies may still bloat the bitrate because of the SFB21 vbr problem (there still remains few MDCT coefficients over 16kHz which can bloat the bitrate).

-Y affects to the bit allocation of all frequencies (SFBs) by disabling over 16kHz noise shaping.


I had read the theory, but my test result did not hold to it. In theory, theory and practice are the same. In practice, theory and practice are different.

I just repeated my test on a different track with the same result. Not dramatic but still has lowpass 16 doing better than -Y. Perhaps -V3 is affecting things in a way you weren't expecting?

Rush - Mission: -alt-preset standard -V3 -b 96
No Lowpass or Y = 6787 bytes
-Y = 6393
--lowpass 16 = 6351
Both = 6351

I am still concluding that there is insufficient energy with lowpass 16 to trigger the extra bits needed for proper rendering of lower frequencies.

Peter
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Posts in this topic
- guidryp   Suggest ~160kbps VBR setting.   Mar 30 2002, 19:27
- - SometimesWarrior   Take a look at this thread for some info on how to...   Mar 30 2002, 21:06
- - Negative Zero   You could also try the --r3mix switch, which resul...   Mar 30 2002, 21:51
- - JohnV   QUOTE Originally posted by Negative Zero You coul...   Mar 31 2002, 01:53
- - mithrandir   Why are there still so many --r3mix followers? It ...   Mar 31 2002, 02:57
- - guidryp   QUOTE Originally posted by mithrandir Although I...   Mar 31 2002, 05:59
- - mithrandir   I say alt-preset extreme -Y creates files with a r...   Mar 31 2002, 08:11
- - JohnV   QUOTE Originally posted by guidryp I am seeking a...   Mar 31 2002, 12:12
- - guidryp   QUOTE Originally posted by mithrandir If you nee...   Mar 31 2002, 18:16
- - guidryp   QUOTE Originally posted by JohnV Well, I don't kn...   Mar 31 2002, 18:55
- - mithrandir   QUOTE Originally posted by guidryp The problem I ...   Mar 31 2002, 21:02
- - JohnV   Yes, VBR would use more bits for harder sections, ...   Mar 31 2002, 21:05
- - guidryp   QUOTE Originally posted by mithrandir make two ...   Mar 31 2002, 22:03
- - guidryp   QUOTE Originally posted by JohnV Yes, VBR would u...   Mar 31 2002, 22:21
- - JohnV   QUOTE Originally posted by guidryp Rush == Metal?...   Mar 31 2002, 22:49
- - guidryp   Well after a bit of testing, I am going with: --a...   Apr 2 2002, 05:36
- - Dibrom   QUOTE Originally posted by guidryp Well after a b...   Apr 2 2002, 10:03
- - guidryp   For whatever reason, I remember --lowpass 16 using...   Apr 2 2002, 14:24
- - JohnV   QUOTE Originally posted by guidryp For whatever r...   Apr 2 2002, 14:35
- - guidryp   QUOTE Originally posted by JohnV Seems that you d...   Apr 2 2002, 15:02
- - indybrett   Thought I might try this for myself. Without goin...   Apr 2 2002, 15:34
- - JohnV   QUOTE Originally posted by guidryp I had read th...   Apr 2 2002, 16:48
- - fewtch   Just my opinion, but if you're gonna do an abrupt ...   Apr 2 2002, 17:05
- - guidryp   QUOTE Originally posted by fewtch Just my opinion...   Apr 2 2002, 17:19
- - scoper   Reading the suggestions of Dibrom and others regar...   Apr 2 2002, 17:25
- - guidryp   QUOTE Originally posted by JohnV Still I think ...   Apr 2 2002, 17:26
- - Dibrom   QUOTE Originally posted by scoper Reading the sug...   Apr 2 2002, 22:12
- - pacohaas   I ripped some complete albums and did some encodin...   Apr 3 2002, 04:25
- - guidryp   Holy Smokes! You ripped 7 albums 5 times just to ...   Apr 3 2002, 12:51
- - Amadeus93   QUOTE Originally posted by pacohaas 1. -b32 hardl...   Apr 3 2002, 13:43
- - JohnV   QUOTE Originally posted by pacohaas 2. While -Y d...   Apr 3 2002, 15:59
- - pacohaas   QUOTE Originally posted by JohnV Again... -Y is n...   Apr 5 2002, 03:08
- - pacohaas   which brings me to yet another idea that I've been...   Apr 5 2002, 03:13


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