Why are mp3 files so big?

Question

Why are mp3 files so big?

Greetings.

I was trying to shift away from Garageband 10 (GB) for doing my voiceover projects to Logic Pro X 10.0.7. My auditions need to be 192 kbps, mono, mp3 files, and the files need to be relatively small. After trying to get the audio settings just right in Logic Pro X (LPX), I ended up with a 6 MB file, which in GB was only about 650 KB!

What gives!?! Why are the files so big in LPX, and how can I reduce them to be closer to the equivalent size that they would be if done in GB?

Thanks for your help.

Posted on Jan 15, 2015 7:45 PM

Reply

Answer 1

Pancenter

Level 6

14,782 points

Jan 15, 2015 8:36 PM in response to Green Lantern

How long is the file in minutes:seconds and what is the sample rate and bit depth.

Both application should be using the same mp3 compression schemes... Do you have logic end markers set correctly, have you listened to the file, is there by any chance, a length of silence at there end.

In the Bounce dialog: make sure normalize is set to off and reverb tails is not enabled

Reply

Answer 2

Jan 16, 2015 10:35 AM in response to Green Lantern

I just want to make sure that you talk about a bounced mp3 files, using the Bounce command and setting up the bounced file in the Bounce Window

A couple of things to be aware of.

What you see in the Bounce Window at the bottom is the required disk space for the PCM (aiff) file not the ,p3 file.
A few math guideline. 1 minute stereo audio file is about 10MB uncompressed (44.1kH, 16bit) and 1MB compressed (mp3, 128kbps), basically factor 10 difference
Using a mono file will cut the file size in half and using other formats changes accordingly

Questions:

GB doesn't let you bounce to mono, how did you do that?

In Logic, you have to select the "File Type: Split" in the Bounce window to create a two split mono files. However, these files are not mono, just the left and right channel as separate audio file.

The mp3 settings in the Bounce Window doesn't provide the Split option. However it has a settings for Mono. I'm not sure if that is for the case when you have a mono Audio Device selected in Logic (If you know the answer to that one, let me know).

Hope that helps

Edgar Rothermich

http://DingDingMusic.com/Manuals/

'I may receive some form of compensation, financial or otherwise, from my recommendation or link.'

Reply