MP3 VBR (Variable Bit Rate)

[Capricorn]

I am not happy with the way in which RM supports recording to MP3 VBR. The UI offers only very limited control to what LAME can actually do - even for the average, non-expert user.

By checking "VBR" and one of the four "x Kbps" options there are just four different VBR settings available. Looking at the distribution of frames in VBR recordings from RM it seems that the approach taken by RM is to treat the selected Kbps value as minimum and 320 kbps is always the max limit. E.g. for VBR 192Kbps this results in frames 192..320 Kbps, for VBR 128 Kbps it is 128..320 Kbps. Having such huge ranges does make sense. If I am going for a lower avg bitrate to give smaller file size priority over sound quality, then why should I include frames with max bitrate?

IMO a much better approach would be to support the LAME "quality setting".
This setting -Vx which has been introduced with LAME 3.98 defines a 10 level scale for sound quality. The different levels are tuned and oriented towards audible quality and not just kbps figures. They range from "-V0" for for max quality (which is actually 320 CBR) to "-V9" for min quality and storage. The recommended setting for good to excellent quality is "-V2" is VBR with 190 Kbps target bitrate (with most frames in 170–210 Kbps). Which is not possible to directly produce from RM.

Actually, a long explanation for a short request:
Would it be possible to support LAME quality setting in one of the next versions?

[Cheryl Wester]

The developer does read the forums so you never know. Thanks for the suggestion.

[prelude]

My experience is that musicreplay doesn't encode VBR at all.
https://forum.applian.com/showthread.php?8496-VBR-Encoding

I do not use encoding with Replaymusic any more because of this.

[Capricorn]

This is exactly what I was thinking when I started this thread:
https://forum.applian.com/showthread.php?8801-RM-5.20-no-real-difference-between-VBR-and-CBR-files

But later I found out that the song (rather old one) I recorded from Spotify did just come with 192 kbps. That's why I didn't notice a difference between 192 kbps CBR and 192 kbps VBR.

I did the same experiment with some recent songs that should come with 320 kbps. Using a tool like Encspot console utility it is obvious that RM indeed does VBR encoding.

However, as I explained in my earlier post the way how it is done is neither transparent to the user, nor is does it support "real world" use cases.

I would really very much appreciate if RM could support
-either LAME quality settings
- or alternatively, any kind of argument string to be passed to LAME on invocation

Hoping that the developer reads and understand this ;-)