VBR CBR comparison, settings problem

mhuessy2 · 8th May 2007, 14:53

hi,

I'm trying to establish new basic mp3 quality settings for my audio work in general and for ripping CDs in particular. My tests seem to have yielded bizarre results. I have been using winamp pro 5, as it allows more detailed user control of the mp3 quality than WMP 10 does.

Does Variable Bit Rate (mono, highest quality) really produce mp3 files that

- have lower reproduction of high frequencies,
- even when optimized to 192-320 kbps,
- and write larger files

than

Constant Bit Rate
CBR
mono
128 Kbps
winamp "Quality" "very high"
44 kHz is what windows file property claims,
44.1 kHz is what AA reports
?

winamp VBR settings:
- with what winamp calls "Quality" at "Very High" (the highest setting)
- with what winamp calls "VBR Q", where 0 is the highest, set to 0
Mono

Before taking any of this too seriously, the rips today were done on new a new Intel DG965WH mobo. the comparison rips were either done on gigabyte mobos, one at least had a sound blaster sound card on it. These tests done using the Intel DG965WH mobo audio. I don't know if these differences may not come from the different drivers involved. In all cases, I have been using relatively up to date XP pro.

I wanted to test the performance of the mp3 options Winamp 5.34 was offering. It allows (and seems to prefer) variable bitrate mp3 stuff. The Mp3 encoder has changed from v1.3 to v 1.33. (In the meantime, I have had to uninstall winamp v5.34 and reinstall v5.24. The misc. dll info at the bottom is thus from v5.24)

I used Adobe Audition 1.5 in View>Spectral, which -- whatever its problems -- allows one to compare its outputs one to another. It displays a frequency (y-axis) vs. time (x-axis), with intensity of color against black representing signal strength. AA 1.5 itself does not offer variable bit rate as a setting.

To make the results easier to compare by eye, I normalized the view area to -1 and zoomed in on the peak. Under AA1.5 spectral view, normalizing just increases the brightness of a given color, it does not change the readout "graph."

I selected a point in a rip of Dance hall of the Dead -- a vocal, not a music file (4:23.723, view begin 4:17.000, length 0:12.384). Then I compared in view>spectral the frequency of the "F" in the word "fine."

My old mp3 rip of this CD (made by some version of winamp 5, CBR, 128, 44,100Hz) (on a different mobo, probably using a sound card & its drivers, not as is the case here, the intel on-board sound with its drivers) had the highest visible peak (4:23.723) of the "F" in the word "fine" reaching

just >19.99 kHz,

which isn't bad for mp3.

The winamp settings (Preferences>media library>CD ripping) had been
CBR
mono
128 Kbps
"Quality" "very high"
44 kHz is what windows file property claims,
44.1 kHz is what AA reports
file length 15,674 kB

The new settings on winamp v5.34, ones that matched those on the prior mobo, were
CBR
mono
128 Kbps
"Quality" "very high"
44 kHz is what windows file property claims,
44.1 kHz is what AA reports
length 15,674 kB

>>> BUT the highest visible peak (4:23.723)= "F high" was ~ >19.72 kHz

As annoying as it is, I'm accepting this >19.72 kHz as the best high I can get off the new mobo & its audio & winamp ripping for the moment.

Even so, I saw that the new encoder 1.33 is outputting fewer "hiss highs" -- stuff above 16 kHz, although the signal (an F) seems OK = comes out at ~20 kHz. The old encoder has visible "squared-off" pyramids above 16 kc, the new encoder goes blackish there, except when signal comes.

Trying VBR, the results are astonishingly bad:

First try:
VBR
Mono
128-320 kbps
"quality" "very high"
vbr q 0 (seems to be the highest)

file length 11,846 kB

The F high is ~ 18.8 kHz

AA can't read this format for technical properties, it can see that it's 44.1 kHz, 16-bit mono,
but at the point where with CBR it reads the bitrate (file format), AA can't understand what it is
seeing = AA 1.5 is pre-VBR, probably

2nd try"
VBR
Mono
192-320 kbps
"quality" "very high"
vbr q 0 (seems to be the highest)

file length 23,474 kB

The F high is ~ 19.6 kHz

==> the file is half again longer than the old CBR, and the highs are not as good.

I uninstalled winamp 5.34 and installed 5.24, very probably the program the existing Dance Hall was ripped with.

It uses mp3 v1.3 (not 1.33)

The results were exactly the same as with win 5.34, mp3 encoder 1.33 = not as good as the old 19.9 kHz copy.

CBR
mono
128 Kbps
"Quality" "very high"
44 kHz is what windows file property claims,
44.1 kHz is what AA reports

file length 15,674 kB

The F high is ~ >19.72

*********************
Misc winamp dll info:
Installed Winamp plugin list
Generated by 'One for Nunz v2.83' on 5/8/2007 at 8:56:41 AM

<< Winamp Information >>

Winamp.ini path is: C:\Program Files\Winamp\Winamp.ini
Plugin directory is: C:\Program Files\Winamp\Plugins
Visualisation directory is: C:\Program Files\Winamp\Plugins
DSP directory is: C:\Program Files\Winamp\Plugins
Skin directory is: C:\Program Files\Winamp\skins

Using Winamp version: 5.24 (Build 703)
Current skin: Winamp Modern (Modern skin)
Sonic Burning Engine is installed
Pro registered version

<< OS Information >>

Running on: Windows XP (Service Pack 2)
Memory available: 1029908 KB

<< Input plugins >>

Nullsoft CD plug-in (CDDB2) v3.2 [in_cdda.dll]
Nullsoft DirectShow Decoder v0.98b [in_dshow.dll]
Nullsoft LineIn plug-in v3.11 [in_linein.dll]
Nullsoft MIDI player 3.11 [in_midi.dll]
Nullsoft Module Decoder v2.2.2 (x86) [in_mod.dll]
Nullsoft MPEG Audio Decoder 3.52 [in_mp3.dll]
Nullsoft MPEG-4 Audio Decoder v0.82 [in_mp4.dll]
Nullsoft NSV Decoder v1.07 [in_nsv.dll]
Nullsoft Vorbis Decoder v1.45 [in_vorbis.dll]
Nullsoft Waveform Decoder 3.01 [in_wave.dll]
Nullsoft Windows Media Decoder 3.21 [in_wm.dll]

<< Output plugins >>

Nullsoft Disk Writer plug-in v2.11 [out_disk.dll]
DirectSound output v2.43 (d) [out_ds.dll] [active]
waveOut output v2.1 (d) [out_wave.dll]

<< Visualisation plugins >>

Advanced Visualization Studio v2.81b [vis_avs.dll] [active]
MilkDrop 1.04d [vis_milk.dll]
Nullsoft Tiny Fullscreen (v2.08) [vis_nsfs.dll]

<< DSP plugins >>

Nullsoft Signal Processing Studio DSP v0.36 [dsp_sps.dll]

<< General Purpose plugins >>

Nullsoft Modern Skins Support v1.21 [gen_ff.dll]
Nullsoft Global Hotkeys v1.31 [gen_hotkeys.dll]
Jump To File Extra v0.97.3 (Build 20) [gen_jumpex.dll]
Nullsoft Winamp Library v3.01 [gen_ml.dll]
One for Nunz v2.83 [gen_nunzio.dll]
Nullsoft Tray Control v2.0 [gen_tray.dll]

<< Media Library plugins >>

Now Playing v2.0 [ml_nowplaying.dll]
Bookmarks v1.01 [ml_bookmarks.dll]
History v1.0 [ml_history.dll]
Nullsoft Local Media v 1.01 [ml_local.dll]
Playlists v1.01 [ml_playlists.dll]
Nullsoft Rip & Burn v1.0 [ml_disc.dll]
Portable Music Player Support v1.04 [ml_pmp.dll]
ml_xpdxs v1.0.4 [ml_xpdxs.dll]

<< Portable Media Player plugins >>

iPod Plug-in v0.51 [pmp_ipod.dll]
Creative NJB Plug-in v0.4 [pmp_njb.dll]
PlaysForSure Plug-in v0.5 [pmp_p4s.dll]

<< Encoder plugins >>

[enc_aacplus.dll]
aacPlus (HE-AAC) Encoder v1.2
aacPlus (HE-AAC) High Bitrate Encoder v1.2
LC-AAC Encoder v1.2
MP4/aacPlus (HE-AAC) Encoder v1.2
MP4/aacPlus (HE-AAC) High Bitrate Encoder v1.2
MP4/LC-AAC Encoder v1.2
[enc_lame.dll]
MP3 Encoder v1.3
[enc_wma.dll]
WMA Encoder v1.1

<< Summary of system components (*.w5s) >>
(These are not included in the plugin counts below)
aacPlusDecoder.w5s (205kb)
jnetlib.w5s (15kb)
playlist.w5s (29kb)
png.w5s (67kb)
tagz.w5s (14kb)
watcher.w5s (26kb)
xml.w5s (88kb)

<< Summary of all dlls in the root winamp folder (*.dll) >>
(These are not included in the plugin counts below)
burnlib.dll (81kb) [not loaded]
libsndfile.dll (218kb) [loaded]
nde.dll (65kb) [loaded]
nscrt.dll (344kb) [loaded]
primosdk.DLL (160kb) [loaded]

<< Summary of installed plugins >>

11 Input plugins installed
3 Output plugins installed
3 Visualisation plugins installed
1 DSP plugin installed
6 General Purpose plugins installed
8 Media Library plugins installed
3 Portable Media Player plugins installed
3 Encoder plugins installed

Total: 38 plugins installed

gaekwad2 · 8th May 2007, 16:42

Question: are you sure you can hear the difference between an 18.8kHz lowpass and a 20kHz one?

The Lame encoder was optimized for best sound quality, not pretty graphs.

8th May 2007, 14:53	#1
mhuessy2 Junior Member Join Date: May 2007 Posts: 3	VBR CBR comparison, settings problem hi, I'm trying to establish new basic mp3 quality settings for my audio work in general and for ripping CDs in particular. My tests seem to have yielded bizarre results. I have been using winamp pro 5, as it allows more detailed user control of the mp3 quality than WMP 10 does. Does Variable Bit Rate (mono, highest quality) really produce mp3 files that - have lower reproduction of high frequencies, - even when optimized to 192-320 kbps, - and write larger files than Constant Bit Rate CBR mono 128 Kbps winamp "Quality" "very high" 44 kHz is what windows file property claims, 44.1 kHz is what AA reports ? winamp VBR settings: - with what winamp calls "Quality" at "Very High" (the highest setting) - with what winamp calls "VBR Q", where 0 is the highest, set to 0 Mono Before taking any of this too seriously, the rips today were done on new a new Intel DG965WH mobo. the comparison rips were either done on gigabyte mobos, one at least had a sound blaster sound card on it. These tests done using the Intel DG965WH mobo audio. I don't know if these differences may not come from the different drivers involved. In all cases, I have been using relatively up to date XP pro. I wanted to test the performance of the mp3 options Winamp 5.34 was offering. It allows (and seems to prefer) variable bitrate mp3 stuff. The Mp3 encoder has changed from v1.3 to v 1.33. (In the meantime, I have had to uninstall winamp v5.34 and reinstall v5.24. The misc. dll info at the bottom is thus from v5.24) I used Adobe Audition 1.5 in View>Spectral, which -- whatever its problems -- allows one to compare its outputs one to another. It displays a frequency (y-axis) vs. time (x-axis), with intensity of color against black representing signal strength. AA 1.5 itself does not offer variable bit rate as a setting. To make the results easier to compare by eye, I normalized the view area to -1 and zoomed in on the peak. Under AA1.5 spectral view, normalizing just increases the brightness of a given color, it does not change the readout "graph." I selected a point in a rip of Dance hall of the Dead -- a vocal, not a music file (4:23.723, view begin 4:17.000, length 0:12.384). Then I compared in view>spectral the frequency of the "F" in the word "fine." My old mp3 rip of this CD (made by some version of winamp 5, CBR, 128, 44,100Hz) (on a different mobo, probably using a sound card & its drivers, not as is the case here, the intel on-board sound with its drivers) had the highest visible peak (4:23.723) of the "F" in the word "fine" reaching just >19.99 kHz, which isn't bad for mp3. The winamp settings (Preferences>media library>CD ripping) had been CBR mono 128 Kbps "Quality" "very high" 44 kHz is what windows file property claims, 44.1 kHz is what AA reports file length 15,674 kB The new settings on winamp v5.34, ones that matched those on the prior mobo, were CBR mono 128 Kbps "Quality" "very high" 44 kHz is what windows file property claims, 44.1 kHz is what AA reports length 15,674 kB >>> BUT the highest visible peak (4:23.723)= "F high" was ~ >19.72 kHz As annoying as it is, I'm accepting this >19.72 kHz as the best high I can get off the new mobo & its audio & winamp ripping for the moment. Even so, I saw that the new encoder 1.33 is outputting fewer "hiss highs" -- stuff above 16 kHz, although the signal (an F) seems OK = comes out at ~20 kHz. The old encoder has visible "squared-off" pyramids above 16 kc, the new encoder goes blackish there, except when signal comes. Trying VBR, the results are astonishingly bad: First try: VBR Mono 128-320 kbps "quality" "very high" vbr q 0 (seems to be the highest) file length 11,846 kB The F high is ~ 18.8 kHz AA can't read this format for technical properties, it can see that it's 44.1 kHz, 16-bit mono, but at the point where with CBR it reads the bitrate (file format), AA can't understand what it is seeing = AA 1.5 is pre-VBR, probably 2nd try" VBR Mono 192-320 kbps "quality" "very high" vbr q 0 (seems to be the highest) file length 23,474 kB The F high is ~ 19.6 kHz ==> the file is half again longer than the old CBR, and the highs are not as good. I uninstalled winamp 5.34 and installed 5.24, very probably the program the existing Dance Hall was ripped with. It uses mp3 v1.3 (not 1.33) The results were exactly the same as with win 5.34, mp3 encoder 1.33 = not as good as the old 19.9 kHz copy. CBR mono 128 Kbps "Quality" "very high" 44 kHz is what windows file property claims, 44.1 kHz is what AA reports file length 15,674 kB The F high is ~ >19.72 ********************* Misc winamp dll info: Installed Winamp plugin list Generated by 'One for Nunz v2.83' on 5/8/2007 at 8:56:41 AM << Winamp Information >> Winamp.ini path is: C:\Program Files\Winamp\Winamp.ini Plugin directory is: C:\Program Files\Winamp\Plugins Visualisation directory is: C:\Program Files\Winamp\Plugins DSP directory is: C:\Program Files\Winamp\Plugins Skin directory is: C:\Program Files\Winamp\skins Using Winamp version: 5.24 (Build 703) Current skin: Winamp Modern (Modern skin) Sonic Burning Engine is installed Pro registered version << OS Information >> Running on: Windows XP (Service Pack 2) Memory available: 1029908 KB << Input plugins >> Nullsoft CD plug-in (CDDB2) v3.2 [in_cdda.dll] Nullsoft DirectShow Decoder v0.98b [in_dshow.dll] Nullsoft LineIn plug-in v3.11 [in_linein.dll] Nullsoft MIDI player 3.11 [in_midi.dll] Nullsoft Module Decoder v2.2.2 (x86) [in_mod.dll] Nullsoft MPEG Audio Decoder 3.52 [in_mp3.dll] Nullsoft MPEG-4 Audio Decoder v0.82 [in_mp4.dll] Nullsoft NSV Decoder v1.07 [in_nsv.dll] Nullsoft Vorbis Decoder v1.45 [in_vorbis.dll] Nullsoft Waveform Decoder 3.01 [in_wave.dll] Nullsoft Windows Media Decoder 3.21 [in_wm.dll] << Output plugins >> Nullsoft Disk Writer plug-in v2.11 [out_disk.dll] DirectSound output v2.43 (d) [out_ds.dll] [active] waveOut output v2.1 (d) [out_wave.dll] << Visualisation plugins >> Advanced Visualization Studio v2.81b [vis_avs.dll] [active] MilkDrop 1.04d [vis_milk.dll] Nullsoft Tiny Fullscreen (v2.08) [vis_nsfs.dll] << DSP plugins >> Nullsoft Signal Processing Studio DSP v0.36 [dsp_sps.dll] << General Purpose plugins >> Nullsoft Modern Skins Support v1.21 [gen_ff.dll] Nullsoft Global Hotkeys v1.31 [gen_hotkeys.dll] Jump To File Extra v0.97.3 (Build 20) [gen_jumpex.dll] Nullsoft Winamp Library v3.01 [gen_ml.dll] One for Nunz v2.83 [gen_nunzio.dll] Nullsoft Tray Control v2.0 [gen_tray.dll] << Media Library plugins >> Now Playing v2.0 [ml_nowplaying.dll] Bookmarks v1.01 [ml_bookmarks.dll] History v1.0 [ml_history.dll] Nullsoft Local Media v 1.01 [ml_local.dll] Playlists v1.01 [ml_playlists.dll] Nullsoft Rip & Burn v1.0 [ml_disc.dll] Portable Music Player Support v1.04 [ml_pmp.dll] ml_xpdxs v1.0.4 [ml_xpdxs.dll] << Portable Media Player plugins >> iPod Plug-in v0.51 [pmp_ipod.dll] Creative NJB Plug-in v0.4 [pmp_njb.dll] PlaysForSure Plug-in v0.5 [pmp_p4s.dll] << Encoder plugins >> [enc_aacplus.dll] aacPlus (HE-AAC) Encoder v1.2 aacPlus (HE-AAC) High Bitrate Encoder v1.2 LC-AAC Encoder v1.2 MP4/aacPlus (HE-AAC) Encoder v1.2 MP4/aacPlus (HE-AAC) High Bitrate Encoder v1.2 MP4/LC-AAC Encoder v1.2 [enc_lame.dll] MP3 Encoder v1.3 [enc_wma.dll] WMA Encoder v1.1 << Summary of system components (.w5s) >> (These are not included in the plugin counts below) aacPlusDecoder.w5s (205kb) jnetlib.w5s (15kb) playlist.w5s (29kb) png.w5s (67kb) tagz.w5s (14kb) watcher.w5s (26kb) xml.w5s (88kb) << Summary of all dlls in the root winamp folder (.dll) >> (These are not included in the plugin counts below) burnlib.dll (81kb) [not loaded] libsndfile.dll (218kb) [loaded] nde.dll (65kb) [loaded] nscrt.dll (344kb) [loaded] primosdk.DLL (160kb) [loaded] << Summary of installed plugins >> 11 Input plugins installed 3 Output plugins installed 3 Visualisation plugins installed 1 DSP plugin installed 6 General Purpose plugins installed 8 Media Library plugins installed 3 Portable Media Player plugins installed 3 Encoder plugins installed Total: 38 plugins installed

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8th May 2007, 16:42	#2
gaekwad2 Foorum King Join Date: Jul 2003 Location: bar2000 Posts: 11,457	Question: are you sure you can hear the difference between an 18.8kHz lowpass and a 20kHz one? The Lame encoder was optimized for best sound quality, not pretty graphs.