So... go ahead and give'er a listen!
The idea is to optimize aacPlus at low bitrates, so the top two links are the important ones:
http://superh.dyndns.org:8000/listen.m3u 40kbps aacPlus V2 (Parametric Stereo) 44.1kHz
http://superh.dyndns.org:8000/test.m3u 32kbps aacPlus V1 (Stereo) 44.1kHz
Here is 128kbps MP3 for reference:
http://superh.dyndns.org:8000/high.m3u 128kbps MP3 (Stereo) 44.1kHz
I think I attacked most of the annoying artifacts without coloring the audio too much. It's always a work in progress, but I'm extremely content with this.
Audio is very dynamic, yet normalized. I hate how much I have to manipulate the stereo image to kill so many artifacts. That's not as true as I'd like it.
Code:
[Common]
Pre amplifier=5
Post amplifier=0.75
Extra loudness=1
Hard limit output=1
Process for low latency=1
Mode=Advanced
[Noise Gate]
Enabled=1
Difference=0
Noise level=2.200000048
[Singleband Compressor]
Enabled=0
Difference=0
Maximum volume=1.5
Maximum value=24576
Attack speed=0.00009
Decay speed=0.100000001
Above Top Limiter=0
[Pre Compressor]
Enabled=1
Difference=0
Delay enabled=0
Maximum volume - Band 1=40010
Maximum volume - Band 2=5500
Attack speed - Band 1=0.000002059
Attack speed - Band 2=0.000002059
Decay speed - Band 1=0.0004578
Decay speed - Band 2=0.0004578
[Multiband Compressor]
Enabled=1
Difference=0
Delay enabled=0
Very high quality enabled=1
Maximum volume - Band -1=4410
Maximum volume - Band 0=4070.000244141
Maximum volume - Band 1=4400
Maximum volume - Band 2=3100
Maximum volume - Band 3=3250
Maximum volume - Band 4=5650
Maximum volume - Band 5=3550
Maximum volume - Band 6=2700
Maximum volume - Band 7=3100
Maximum volume - Band 8=3950
Attack speeds linked=1
Attack speed - Band -1=0.000027837
Attack speed - Band 0=0.000027837
Attack speed - Band 1=0.000027837
Attack speed - Band 2=0.000027837
Attack speed - Band 3=0.000027837
Attack speed - Band 4=0.000027837
Attack speed - Band 5=0.000027837
Attack speed - Band 6=0.000027837
Attack speed - Band 7=0.000027837
Attack speed - Band 8=0.000027837
Decay speeds linked=1
Decay speed - Band -1=0.002081846
Decay speed - Band 0=0.002081846
Decay speed - Band 1=0.002081846
Decay speed - Band 2=0.002081846
Decay speed - Band 3=0.002081846
Decay speed - Band 4=0.002081846
Decay speed - Band 5=0.002081846
Decay speed - Band 6=0.002081846
Decay speed - Band 7=0.002081846
Decay speed - Band 8=0.002081846
Above Top Limiter=1
Clipping enabled=1
Postprocessing enabled=1
Relative clip position - Band -1=2.508771658
Relative clip position - Band 0=2.508771658
Relative clip position - Band 1=2.508771658
Relative clip position - Band 2=1.857142687
Relative clip position - Band 3=1.857142687
Relative clip position - Band 4=1.352941036
Relative clip position - Band 5=1
Relative clip position - Band 6=0.801801801
Relative clip position - Band 7=0.709401608
Relative clip position - Band 8=0.801801801
Final limiter value=0.5
Final limiter decay speed=0.000239358
Final limiter clipping=0.307189584
Equalizer enabled=1
Equalize before multiband-compression=0
Equalizer position - Band -1=1.702702761
Equalizer position - Band 0=1.702702761
Equalizer position - Band 1=1.352941036
Equalizer position - Band 2=1
Equalizer position - Band 3=1
Equalizer position - Band 4=1
Equalizer position - Band 5=1
Equalizer position - Band 6=1
Equalizer position - Band 7=1
Equalizer position - Band 8=1
[Stereo]
Enabled=1
Delay enabled=0
Difference=0
Center bass=1
AZIMUTH limit=75.61000061
AZIMUTH change speed=0.300000012
Image phase amplifier=1.600000024
Image phase amplifier maximum angle=90
Image phase amplifier maximum separation strength=75.169998169
Image width amplifier=0.75
Extra phase shift=0
Mono or stereo only=-1
[Channel Delay]
Enabled=0
Left Delay=0
[Output Filter]
Enabled=1
Lowpass filter=16500
Highpass filter=20
[Final Pre-Limiter]
Enabled=1
Difference=0
Pre-amp=1.230895996
Response time=0.025
[Final Limiter]
Enabled=1
Difference=0
Pre-amp=1.595456004
Response time=0.0125
[FM Transmitter]
Enabled=0
Pre-emphasize=0
Pre-emphasis time=50
Output is pre-emphasized=0
Stereo encoder enabled=0
RDS encoder enabled=0
Pilot signal volume=9
RDS signal volume=4.5
FM overdrive volume=1
RDS PS text=2s:STEREO/2s:TOOL/<1=1.5s,2..-2=2t,-1=1.5s:WWW.STEREOTOOL.COM
RDS RadioText text=60s:Stereo Tool: Professional Audio Processing - www.stereotool.com/30s:Stereo Tool by Hans van Zutphen, 1999-2008 - www.stereotool.com
RDS PTY=0
RDS PI=65535
RDS Alternative frequency 1=0
RDS Alternative frequency 2=0
RDS Alternative frequency 3=0
RDS Alternative frequency 4=0
RDS Alternative frequency 5=0
RDS Alternative frequency 6=0
RDS Alternative frequency 7=0
RDS Alternative frequency 8=0
RDS Alternative frequency 9=0
RDS Alternative frequency 10=0
RDS Alternative frequency 11=0
RDS Alternative frequency 12=0
RDS Alternative frequency 13=0
RDS Alternative frequency 14=0
RDS Alternative frequency 15=0
RDS Alternative frequency 16=0
RDS Alternative frequency 17=0
RDS Alternative frequency 18=0
RDS Alternative frequency 19=0
RDS Alternative frequency 20=0
RDS Alternative frequency 21=0
RDS Alternative frequency 22=0
RDS Alternative frequency 23=0
RDS Alternative frequency 24=0
RDS Alternative frequency 25=0
RDS TP=0
RDS TA=0
RDS Music=1
RDS Artificial Head=0
RDS Compressed=1
RDS Dynamic PTY=0
RDS RadioText Enabled=1
RDS ClockTime Enabled=1
FM Transmitter Calibration Enabled=0
MPX Oversampling mode=Follow main Quality setting
FM Transmitter Calibration - Volume 20 Hz=1
FM Transmitter Calibration - Volume 40 Hz=1
FM Transmitter Calibration - Volume 80 Hz=1
FM Transmitter Calibration - Volume 160 Hz=1
FM Transmitter Calibration - Volume 320 Hz=1
FM Transmitter Calibration - Volume 640 Hz=1
FM Transmitter Calibration - Volume 1280 Hz=1
FM Transmitter Calibration - Volume 2560 Hz=1
FM Transmitter Calibration - Volume 5120 Hz=1
FM Transmitter Calibration - Volume 10240 Hz=1
FM Transmitter Calibration - Volume 19000 Hz=1
FM Transmitter Calibration - Volume 23000 Hz=1
FM Transmitter Calibration - Volume 28000 Hz=1
FM Transmitter Calibration - Volume 33000 Hz=1
FM Transmitter Calibration - Volume 38000 Hz=1
FM Transmitter Calibration - Volume 43000 Hz=1
FM Transmitter Calibration - Volume 48000 Hz=1
FM Transmitter Calibration - Volume 53000 Hz=1
FM Transmitter Calibration - Volume 57000 Hz=1
FM Transmitter Calibration - Phase shift 20 Hz=0
FM Transmitter Calibration - Phase shift 40 Hz=0
FM Transmitter Calibration - Phase shift 80 Hz=0
FM Transmitter Calibration - Phase shift 160 Hz=0
FM Transmitter Calibration - Phase shift 320 Hz=0
FM Transmitter Calibration - Phase shift 640 Hz=0
FM Transmitter Calibration - Phase shift 1280 Hz=0
FM Transmitter Calibration - Phase shift 2560 Hz=0
FM Transmitter Calibration - Phase shift 5120 Hz=0
FM Transmitter Calibration - Phase shift 10240 Hz=0
FM Transmitter Calibration - Phase shift 19000 Hz=0
FM Transmitter Calibration - Phase shift 23000 Hz=0
FM Transmitter Calibration - Phase shift 28000 Hz=0
FM Transmitter Calibration - Phase shift 33000 Hz=0
FM Transmitter Calibration - Phase shift 38000 Hz=0
FM Transmitter Calibration - Phase shift 43000 Hz=0
FM Transmitter Calibration - Phase shift 48000 Hz=0
FM Transmitter Calibration - Phase shift 53000 Hz=0
FM Transmitter Calibration - Phase shift 57000 Hz=0
[Direct soundcard access]
Enabled=0
Device ID=Microsoft Sound Mapper
Volume=1
Buffer size=1
Send to Winamp=Nothing
ASIO Override channel 1=4
ASIO Override channel 2=5
[Low latency output]
Enabled=0
Device ID=
Volume=1
Buffer size=0.079999998
ASIO Override channel 1=2
ASIO Override channel 2=3