# Solved: MP3 bitrate batch convert



## renegade X (May 27, 2003)

Hello all, someone please help me. Through the years I have collected soooo many MP3s and even converted all of my audio CDs from wave to MP3. Well now I have a huge mess of mixed bitrates. In spare time I have been trying to convert every one of these to 192 stereo, but I am getting nowhere. Is there a way to do all these in one swoop? Currently I am using Nero's wave editor, but can only do these one at a time. Can someone please give me a better option? Maybe a program that does batch converts, or a VBscript?


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## stantley (May 22, 2005)

CDex will do that for you, but to get the best quality you should re-rip them to 192.

The only thing you're going to get converting an Mp3 file from a smaller bitrate, say 128 kbps, to 192 kbps is a larger file size with the same or slightly less quality as the 128. It's pretty much a waste of time.

Even converting down from a higher bitrate to 192 will give you less quality then re-ripping directly to 192.


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## renegade X (May 27, 2003)

Not a waste of time at all. When a song ends that was 192 and goes to a 128, I will have to turn the volume up. When I was a newbie with bitrates and burning CDs, I blew all of the speakers in my truck, thanks to the bitrate jacking up my volume. Re-ripping is not an option, since I have 100s of CDs. I will check this program out, thanks. Anyone else know of other programs for me to try?


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## stantley (May 22, 2005)

Bitrate has nothing to do with volume. Volume depends on how high the levels were set on the original recording. Some CD's have an average level, many CD's have the volume boosted up. It's probably just a coincidence that you noticed a certain bitrate had a certain volume.

Rather than change the bitrate, run all of your mp3 files through MP3Gain which will make all the volume levels consistent. The default level for MP3Gain is 89 dB which I find to be a little low. Set it to 92 or 93 and run all your files through at the same level.

You can run your whole library at once, because it will go down through sub-directories, however it will take a long time.


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## renegade X (May 27, 2003)

AHHA!!!! You have found my answer. Since the bitrate doesnt make a difference, I can turn them all back to 128 to save space?


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## stantley (May 22, 2005)

renegade X said:


> AHHA!!!! You have found my answer. Since the bitrate doesnt make a difference, I can turn them all back to 128 to save space?


Yes, but again you'll lose a little bit of quality, however unless your listening through a good stereo system, you might not even notice. You could test it out by taking 192 song, convert it to 128 and listen to one then the other.

I've been to too many rock concerts in my lifetime for my ears to notice much of a difference.


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## renegade X (May 27, 2003)

LOL I have a bit of damage inside as well. Mostly from my own guitar amps. Thank you so much for saving me hours of wasted time. Both programs work great!

BTW I love your info in "Experience".

Happy Thanksgiving!


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## MysticEyes (Mar 30, 2002)

stantley said:


> CDex will do that for you, *but to get the best quality you should re-rip them to 192.*
> 
> The only thing you're going to get converting an Mp3 file from a smaller bitrate, say 128 kbps, to 192 kbps is a larger file size with the same or slightly less quality as the 128. It's pretty much a waste of time.
> 
> Even converting down from a higher bitrate to 192 will give you less quality then re-ripping directly to 192 kbps.


A little too vague there. You can can much better quality, actually virtually identical (transparent) to the CD (to most folks hearing in blind tests), by using* Lame *and* VBR. * With CDex choose alt- preset- standard instead of 192 kbps. The resultant file size is about the same as a standard CBR 192, but with *much* better fidelity. The reason being when the music needs it will hit 320 kbps.

_-preset standard

This preset should generally be transparent to most people on most music and is already quite high in quality.
The resulting bitrate should be in the 170-210kbps range, according to music complexity._

Heres a pic to show bitrate distribution, in this case I altered the -preset, changing the low end to 96 kbps.










Notice the amount of information above 192 kbs, yet the file size will be just a hair larger at a 195 kbps. Variable Bit Rate, just like in video, is always the way to go.


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## stantley (May 22, 2005)

MysticEyes said:


> With CDex choose alt- preset- standard


Yes, I've used that before and I have a question. When you use that the default for VBR Quality is VBR 2 and default for Output Samplerate is Auto.

Are those the settings you use or should they be changed?


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## MysticEyes (Mar 30, 2002)

stantley said:


> Yes, I've used that before and I have a question. When you use that the default for VBR Quality is VBR 2 and default for Output Samplerate is Auto.
> 
> Are those the settings you use or should they be changed?


It does not default to 'Auto' for me (version 1.70 beta 2). 44100 (44.1 KHz) is the standard (more or less) for mp3.

Actually alt- preset- standard is obsolete with the latest Lame, but is almost identical to the latest settings and does the trick for those who don't want to go into the often arcane Lame variables. For CDex, it's the one to use.


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## stantley (May 22, 2005)

Thanks,

What about the VBR Quality settings, VBR 0 through VBR 9. What should that be set to?


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## MysticEyes (Mar 30, 2002)

stantley said:


> Thanks,
> 
> What about the VBR Quality settings, VBR 0 through VBR 9. What should that be set to?


Use VBR 2. CDex's internal Lame does not allow for the full (and often very confusing) switches. That said, the preset -standard, VBR 2 (128 to 320 kbps) and 44.1KHz settings will produce excellent results.

You could update to the latest LAME 3.98.

http://www.free-codecs.com/Lame_Encoder_download.htm

Simple find and copy the new *lame_enc.dll* into Cdex. You may rename the old first if you like.


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