Constant v. Variable Bit Rates

hi when saving down from wav to mp3 to upload as a podcast I am always given this option. My gut tells me to go with a constant, but what is the difference and when would you use the variables?

1 Like

For the highest quality, I would go with CBR. Constant Bit Rate means the bit rate is a constant for the whole song. I would recommend the highest setting (320 kbps).

Variable means the bit rate changes (varies) throughout the song. This setting is best if you really want the smallest file and are concerned about space.
Still the difference is very minimal (sound wise) and you probably will not hear a difference. Unless you choose 160 kbps vs 320 kbps, then you could hear a difference.
If you aren’t concerned with hard drive space, go with the CBR at 320 kbps. It will still be a small file and you will get the best possible lossy overall.
Hope this helps

1 Like

thanks - yup, I save all MP3’s at 30 CBR, but I am glad to understand why I do it!!

Considering that a MP3 file is compressed to 85-90% of the original source file (wav) it has to squelch everything it can most notable bass roll-off and a crushed mid. what you end up with is a miracle to be honest for the filesize. There again most of our speakers we listen to on a daily basis these days, have no bottom end anyway. (phones, iPads tinny radios etc.)