How standard is VBR for MP3 files? (1 Viewer)

[Vince Maskeeper]

I'm encoding some older RA files to MP3 for archiving purposes. These are pretty mediocre Real Audio files, so the quality of MP3 at 96k is more than enough.

I tried some experiementing with VBR on some files, and found that i could get about 50% the files size with many by making it variable between like 32k and 96k using CDEX. The issue I have is that I'm under the impression that VBR causes fits for some devices.

I'm mainly interested in compatibility with:
PC playback in Winamp (no problems there- seems fine)

IPOD playback (Don't have mine yet to test it, does anyone else use VBR for IPOD?)

Possible future in-dash MP3 player for car (Does anyone have one and use VBR files?)


I've noticed CDEX has several settings for VBR Specifically:
METHOD: Default, Old, New, MTRH, ABR
QUALITY: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
VERSION: MPGI, MPGII, MPGII.5

Does anyone have any suggestions on getting good compression sizes for non-critical (voice only) material with the best compatibility for multiple devices?

 

[Max Leung]

You may need to encode mp3s as joint-stereo for problematic players. For example, the Panasonic RP91 DVD player I have doesn't like VBR mp3s unless they are joint-stereo encoded. Although, I did upgrade the firmware a while ago, so for all I know it is fixed. But I doubt it.

 

[Vince Maskeeper]

Max,

How does mono work? All these tracks are mono.

-Vince

 

[Max Leung]

Oh, if they are all mono, the encoder might have them flagged as mono anyways, and there won't be anything to worry about (aside from VBR compatibility itself). I hope.

You could probably use WinAMP or some other player that gives you details on the mp3 file that will tell you how it was encoded.

Good luck!

 

[Rob Gillespie]

Possible future in-dash MP3 player for car (Does anyone have one and use VBR files?)

I use a Kenwood, the first model available in this country. I've had for about two years now and it plays anything I can throw at it.

All of my MP3s are encoded with Lame using the R3mix.net recommended VBR settings. Joint Stereo is always employed as it's supposed to be more accurate with the rest of the settings they use.

Vince - remember that MP3 CD set I did for you and the rest of the mods a while back? RAF had problems playing the discs on his Panny RP-91, but when I sent him a Joint Stereo version it worked fine.

 

[DonRoeber]

Anyone know how the Tivo with Home Media Option handles VBR encoded MP3s? I just finished encoding my entire CD collection with LAME's --alt-preset=standard flag.

These MP3s work fine with iTunes and my iPod, and Winamp, of course.

 

[Vince Maskeeper]

Can you list what these are? I tried to go to that site, and it seemed to not be there. CDEX uses LAME as its backend encoder- so the settings should be the same.

-V

 

[Rob Gillespie]

--nspsytune --vbr-mtrh -V1 -mj -h --athtype 3 --ns-sfb21 2 -Z --scale 0.98 -X0

The VBR is from 96 to 320kbps, Joint Stereo, with a low-pass filter of 19.5khz.

This is the setting I've been using for ages and to my ears the files sound the same as the original source CDs when played through my main system. Perhaps better equipment would yield differences (that said, it's not as if my stuff is rubbish).

If you go over to www.hydrogenaudio.org you'll probably find newer refinements with their -alt preset standard settings. This isn't something I've tried myself as it gets to the point where you have to stop experimenting and just use the damn thing. R3mix.net stopped posting updates some time back as the author felt he'd gone as far as he could with it. As you said, it looks like the site is now down.

 

[Camp]

When portable players and car stereos first began appearing VBR compatibility was an issue. Today, most of these devices generally do a much better job. Shame on any company who releases an MP3-capable device that doesn't do VBR perfectly.

I have noticed a few devices that do not like extremely low bit rate files. Sony Clie PDA's and a few Keychain MP3 players I've tried seemed to have intermittant problems with anything below 96kbps.

BTW, you mentioned the iPod...mine has played every file I've ever thrown at it.

 

[Scott L]

In my experience encoding small Divx files, if I used VBR mp3s (encoded in razorlame) it would play fine until I tried to go forward or backward in the timeline. The audio would get our of sync with the video.

However for CD ripping I always use 192kbps VBR.

 

[Scott Wong]

All of my mp3's are encoded using VBR. (alt-preset standard) I don't have a deck in my car that can play mp3's so I can't comment on that. However, I purchased a portable Sony CD/MP3 player last month. It *does* have problems playing certain files. I've got approx. 20GB worth of .mp3's and it's problematic with a dozen or so. That's a pretty good ratio as far as I'm concerned but still disappointing, nonetheless. I have not figured out why it only happens on the tracks that it does. It doesn't seem as though there is any rhyme nor reason. The player plays the track just fine, but there are annoying little "pops" every so often throughout the track.

When I do upgrade the deck in my car, I won't be going Sony. :frowning:

Scott.

 

[Kimmo Jaskari]

Well, I've had problems playing plain 128kbit CBR files on some equipment as well, so problems aren't exclusively limited to VBR files.

For all intents and purposes, VBR files play on everything. Compatibility isn't a reason not to use it.

Sure, you can get unlucky and find a device that won't work right, but the gains from using VBR are such that it simply doesn't make sense to use anything else (unless you go with 320kbit CBR to make sure you get absolute max quality and don't care about file size - but if you are that determined to get perfect quality, you'd be better off using a lossless compression format instead, IMHO.)

 

[Camp]

Well, I've had problems playing plain 128kbit CBR files on some equipment as well, so problems aren't exclusively limited to VBR files.

There are other factors besides the bit rate. The encoder you used will play a big role in the quality of the MP3. The source could have been poorly copied to the hard drive prior to encoding. The PC it was encoded on could have an effect on the quality as well: Were system resources taxed during the encoding process? Was the song ripped directly from CD to MP3 on a system with a poor performing CD drive?

 

[David Lawson]

Vince, I've had no problems with VBR on my in-dash Jensen MP3510.

We might need some clarification on the "Joint Stereo" setting, though. According to iTunes, it's useful only for encoding rates 128K and lower, which I never use. Does this setting even matter for mono files?