exporting MP3

Hello in ver 2.41 and 2.42 when I export to an mp3 the track goes up and down in volume or kind of fades then comes back…I am not sure If older versions did this I cant remember but I never noticed it like I do now.
Also to get around this what i have to do is export to a .wav then load the .wav and eport that to mp3 and the volume and track is consitent.

Please help

There shouldn’t be any difference unless the peaks exceed 0dB and the WAV gets [u]clipped[/u].

if I export to wav to track does not fade in and out
if i export to mp3 it fades up and down

if i load the wave then export to mp3 it works and no fading up and down…is there a way I can check to see if it is clipping past 0db?

Ok thank you for putting me on the right track. When I use the → Analyze–> Find Clipping

It puts at the bottom of all my tracks a clipping track. when I play the tracks in audacity it is now fine but when I export to mp3 it is still clipping.
How to I apply the analyze to all the tracks before I export?

How to I apply the analyze to all the tracks before I export?

Audacity has already scanned/analyzed your file and the Amplify or Normalize effect can will bring your peaks down (or up) to 0dB. (I believe Normalize defaults to -1dB but you can change the setting for either one.)

A couple more things - Audacity shows potential clipping. It doesn’t “know” anything about distortion or the wave shape.

Also, MP3 can go over 0dB (without clipping) but your analog-to-digital converter will clip if you play it at “full digital volume”.

And, MP3 is lossy compression which changes the wave shape. Some peaks end-up higher and some peaks end-up lower. You can have a WAV (or Audacity file) that’s normalized for 0dB peaks but after making an MP3 it may go over 0dB. A lot of MP3s ripped from CD go slightly over 0dB. Usually, that’s not a big deal but some people normalize to -1dB before making an MP3 to allow for that.

Thank you for all your help

What would the limiter do as opposed to normalized

In a Limiter, you set a “threshold” level, which is the maximum peak level that you want. The Limiter squashes down any peaks that are beyond the “threshold” level, thus ensuring that the waveform does not exceed that level. The usual purpose of a limiter is to allow the audio to be amplified a bit more without clipping. Excessive use of a limiter can make the audio sound distorted.