Volume Level of MP3 Audio Mixdown?

I created an MP3 of my song using the Export Audio Mixdown dialog. I selected one audio track in the channels section on the left for export. I had the level for the track set pretty high, and the meters showed that the output level was almost all the way to the top. I opened the MP3 in Audacity, and the waveform filled the vertical space without clipping, so the level in the MP3 looked correct.

But when I played the MP3, the volume level was extremely low. This makes me wonder if there is a volume setting in an MP3 file that’s distinct from the height of the waveform.

I noticed that in the MixConsole window, the level for Stereo Out was set really low. So I set it higher to see what effect that would have and did the export again. Everything was the same except now the MP3 played back at an acceptably high level. This is odd because I did not have Stereo Out selected as an export channel. I just had the one audio track selected.

Can someone explain these strange MP3 and Cubase behaviors?

Thanks…

Is the track routed to Stereo Out?

Yes.

But it’s puzzling that the waveform looked fine in Audacity even when the Stereo Out level was set low.

That could be just display zoom level.

Thanks for your suggestion. Because of it, I did some investigating in Audacity, and figured out what is going on.

I am working on a Windows PC. It turns out that when you set the volume of the PC speakers in Audacity, it doesn’t just set the volume in the app, it sets the global volume for Windows.

So when I turned up the volume in Audacity, the volume was now louder when I tried the next attempt at an audio mixdown MP3, for which I set the MixConsole level of Stereo Out higher. This made me think that the MP3 file was somehow louder due to an internal setting in the file that was caused by the by the higher level I had set for Stereo Out. But it was just that Audacity set the PC volume higher.

All of this stuff is so complicated but it’s pretty easy to confuse yourself, which is what I did yesterday.