Music files encoded in LAME V5 don't sound great on anything except portable listening situations[/url] (i.e. earbuds connected to a DAP):
Portable: listening in noisy conditions, lower bitrate, smaller file size
-V4 (~165 kbps), -V5 (~130 kbps) or -V6 (~115 kbps) are recommended.
-V6 produces an "acceptable" quality, while -V4 should be close to perceptual transparency.
Better results would be achieved by increasing the bitrate:
Very high quality: HiFi, home, or quiet listening, with best file size
-V0 (~245 kbps), -V1 (~225 kbps), -V2 (~190 kbps) or -V3 (~175 kbps) are recommended.
These VBR settings will normally produce transparent results. Audible differences between these presets may exist, but are rare.
[edit] Very high quality: HiFi, home, or quiet listening, with maximum file size
-b 320 is an alternative to the VBR settings above.
This CBR mode will maximize the MP3's bitrate and overall file size. The extra space may allow for some parts of the audio to be compressed with fewer sacrifices, but to date, no one has produced ABX test results demonstrating that perceived quality is ever better than the highest VBR profiles described above.
RE: Problems using V5 with LAME 3.99.5
And people wonder why some still use LAME 3.97? New isn't always better.