absolute best audio quality settings for lame?
Reply #15 – 2010-09-18 15:36:20
My favorite Lame usage is -V0 -b 320 --ns-bass -8 --ns-alto -8 --ns-treble -5 --ns-sfb21 5 --lowpass 16.7, and it leads to an average bitrate of 295 kbps (after applying the fast and lossless mp3packer procedure afterwards). -b 320 makes best use of the available space for audio data. The available space will not be totally filled with audio data however, which makes sense for the mp3packer procedure to kick off the unused space. A negative value for --ns-bass, --ns-alto, --ns-treble makes Lame more defensive and brings improvement for certain kind of problem samples. Whether or not it's worth while is a matter of personal taste, as is already the usage of -V0. Lame quality is usually excellent without these additions and with a lower quality level. On the other hand small file size isn't an important thing any more for many people with music players of giant capacity around. --ns-treble -x --ns-sfb21 x makes sure that the increased defensiveness doesn't work for sfb21, that is the frequency range above 16 kHz. Precision of sfb21 encoding can lead to inadequate inefficiency of the overall encoding. That's why Lame automatically reduces sfb21 accuracy for quality levels below V2. Not a bad idea as we aren't sensitive to this frequency range anyway and it contains little musical information. For V2 and above the same can be achieved by using the -Y switch. Alternatively an explicit lowpass can be used as I do it in my setting above. All a matter of taste. I have no idea whether this -V0 variant leads to a better quality than plain -b 320. Since 3.98 I like the VBR quality of Lame, that's why I personally prefer VBR to CBR. I did positively ABX the above setting against plain -V0 for certain problem samples, but I did no ABXing against CBR 320. Maybe I should do it some day.