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Hydrogenaudio Forums > Lossy Audio Compression > MP3 > MP3 - General
jyang
I know this is a kind of a newbie question, so I'll keep it short... I noticed in Lame 3.97 (using CDex as a frontend) all the alt-presets default to 128kbps as the min, but there actually isn't anything to lose by going down to 32kbps (in Lame, I know iTunes does it entirely differently), right?

Thanks much!!
shadowking
Lame seems to use < 128k frames in v3.97 and 3.98. I would set the min to 32k and max to 320k. You should be able to access all the presets like this:

Min = 32 , Max = 320k
Joint-Stereo
Quality=high (ignored if vbr method=new)
VBR Method = New
VBR quality = 0...9 (e.g - choose 2 for -V2 aka: alt preset standard)

Seems to work but I've only briefly tested things.
pdq
Years ago LAME had a bug that occasionally caused it to use too low bit rate in VBR. The workaround was to set the minimum to 128 kbps. Since then this problem has been fixed so it is now safe to allow 32 kbps minimum.
jyang
Thanks, I'll use min = 32kbps, then. I had been putting together a mix dvd-r for someone, and had really wondered about the potential space savings -- every little bit really helps, even if it's just a little from here and there..

Thanks for your help -- I appreciate it.
2Bdecided
I haven't tried this, so maybe it make zero difference, but...

Why over ride the default pre-sets / recommended settings? Maybe it is safe, but it's not what's been widely tested.

Lame drops to 32kbkps for digital silence anyway. As has been said, the old 128k lower limit isn't there anymore anyway.

Cheers,
David.
shadowking
I think those frontends like cdex originated from a time when mp3 settings weren't safe and special presets were needed for efficient encoding. No one trusted anything or any setting. Take a look at v3.90 - all you need or want is -APS / --preset standard --alt-preset standard...vbr fast / old..It never looked good IMO. The other encoders never needed this because they had a proper quality scale from the start.

V3.98 looks so much more confident & tidy just like the other encoders - just choose your quality from 0~9.. In the future frontends will adjust to the new system and hopefully get rid of silly options
trev
QUOTE (jyang @ Aug 20 2007, 18:15) *
Thanks, I'll use min = 32kbps, then.

i know your first post said your using 3.97, but just make sure your definitely using that version, as if it's an older version you may have problems if you tell it to encode below 128kbps, as was stated.

it's a lot safer either way to just use the corresponding presets, either use -V2 (or any number, lower is better quality) or if that doesn't work then you probably have an older version of lame, so use the alt-presets. (or get the newer lame instead)
Rio
I'm using LAME 3.97 EXE within Audiograbber, preset standard. So far it automatically uses 32kbps as minimum bitrate, as confirmed with EncSpot. Using the DLL at -V2, IIRC, sets the minimum at 80kbps though.
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