Bit Rates (VBR, ABR & CBR)

[jonniebag]

I've been messing about converting my flac files into both .m4a and .mp3 versions and am initially interested in the VBR, ABR & CBR settings.

I'd like to match or better the iTunes lossy format using the aac codec, so it would firstly be good to know how to recreate this.

Secondly, if I wanted the very best quality for both .m4a and .mp3 formats, which type of bit rate and associated kbps values should you use in each conversion, as well as encoding option?

I also notice that there is an advanced options tab for .mp3's, so any tips here would be great.

[Spoon]

Re: Bit Rates (VBR, ABR & CBR)

Go for 320kbps CBR this is the best standard mp3 can have.

[jonniebag]

Re: Bit Rates (VBR, ABR & CBR)

Would you change any of the settings under the encoding drop down or on the advanced tab?

Any tips for .m4a production?

[Spoon]

Re: Bit Rates (VBR, ABR & CBR)

No need to change anything else, for Nero aac try VBR Quality 1 (425kbps)

[Porcus]

Re: Bit Rates (VBR, ABR & CBR)

I've been messing about converting my flac files

[...]

Secondly, if I wanted the very best quality

Merely picking the highest bitrate available, does kinda defeat the purpose of lossy codecs. If you are worried whether 320 is audibly better than, say, 192, then stick to FLAC until you have tested thoroughly.

You don't say anything about whether you want to keep your FLACs or not. For example, you might want to keep the FLACs for archive or for listening at home, but make a lossy library for portable listening. In that case, why don't you start low (128?) and then replace if they aren't good enough?


Anyway, the choices Slow (high quality) and Fast (low quality) mean something. A lossy encoder tries to make the best of quality out of a given bit rate, (or for a given quality, pack as good as possible). That takes time and effort to find the best or pack the best, so choose Slow if you can leave it overnight. (My collection took two weeks to convert ...)

[jonniebag]

Re: Bit Rates (VBR, ABR & CBR)

It's flac for my sonos setup at home, attached to my existing hi-fi setup, where I intend to import the .m4a or .mp3 into my iphone for travelling about.

I'm torn between keeping the files small, so I can get as much as possible on the device, and not loosing any of the sound quality.

I think I'll just keep experimenting, so thanks for all the tips.

[garym]

Re: Bit Rates (VBR, ABR & CBR)

It's flac for my sonos setup at home, attached to my existing hi-fi setup, where I intend to import the .m4a or .mp3 into my iphone for travelling about.

I'm torn between keeping the files small, so I can get as much as possible on the device, and not loosing any of the sound quality.

I think I'll just keep experimenting, so thanks for all the tips.

I do the same thing (except FLAC for squeezebox system at home). I use mp3 created from FLAC with LAME -V2 for a mirror library I use on iphone, ipods, ipads. I haven't bothered to test, but I suspect I could get by with even smaller files (probably -V4 or -V5). You should install foobar2000, the ABX component, then do some tests of FLAC against -v2, -v3, -v4, -v5, etc. Then you can decide for yourself at what level of lossiness a file is no longer transparent compared back to the original.

[Jeff Flowerday]

Re: Bit Rates (VBR, ABR & CBR)

I suggest doing -V0 even if you can't hear the difference with your current mp3 reliant gear. Doesn't mean you might not have something better down the road and wish you had the best mp3s possible.

2 libraries -V0 mp3s and flac is the best way to go IMO.

That said if you have the flacs you can easily recreate the mp3s if need be.


.02

[Porcus]

Re: Bit Rates (VBR, ABR & CBR)

I'm torn between keeping the files small, so I can get as much as possible on the device, and not loosing any of the sound quality.

I think I'll just keep experimenting, so thanks for all the tips.

Since you keep the FLACs, you can just do the conversion over again. If you are jogging with 320 CBR on the iPod, then it is a major overkill in bitrate.

If you could see yourself using Linux, then there is this virtual file system: http://sysadminsjourney.com/content/...mp3-fly-mp3fs/
Then you don't have to maintain two libraries (... updating tags on both, etc) – your file system will 'see' mp3's which are produced the moment you read the file.

(Disclaimer: haven't used it.)