ACX check pass - MP3 all red lines!!!

This is the first audiobook I’ve put through ACX. I’ve just produced 12 chapters of a book using the same setup and processes throughout. All of the files passed ACX check in Audacity but two failed in Audio Analysis after I uploaded them. Looking at the .aup files for these two, I can’t see what is wrong but when I dragged the MP3s into Audacity they showed a mass of red lines. The ACX check for one of the .aup files was: Peak level -3.20dB Pass; RMS level -20.4dB Pass; Noise Floor -72.18dB Pass. However, The ACX check for the MP3 file for that one shows Peak level -1.67dB Fail; RMS level -14.18dB Fail, Noise Floor -66.47dB Pass. What have I done wrong? The only way I can get the MP3 file to pass the ACX check is to run RMS Normalise and Limiter again on it in Audacity. But is that too much processing as I ran before to produce the .aup file that passed? I’m confused, please advise.

My guess is your track gain slider

is at about +6dB when you make the mp3.

What he said.

I’m not a fan of those sliders. They seem to be a convenient “gift,” but they’re lying to you. If you use them, the blue waves and the bouncing sound meter stop matching, and worse yet, the waves and the exported show stop matching.

It used to be worse. If you just touched the L/R (Left-Right) slider, Audacity used to convert your mono show (one blue wave) to stereo (two blue waves) entirely in the background. It still does that if you move the L/R sliders, but now it converts it back to mono if you move the slider back to the center.

Was that it?


Looking at the .aup files for these two

A word about that. AUP isn’t a sound file. It’s a text list of instructions of how Audacity should make your show out of the sound snippets in the _DATA folder. The AUP file and the _DATA folder need to be in the same location or folder for the show to open. They have to be named the same and it has to be the name you gave them in Audacity. Don’t put the AUP file inside the _DATA folder.

There’s a couple of more rules, but those are the biggies. The new and improved Audacity version 3 (out shortly) doesn’t use AUPs any more, but it will open your old shows.

For the best production stability, you should export a perfect quality WAV (Microsoft) 16-bit sound file of your raw reading, and then export another WAV of your chapter Edit Master. Too many people discover their old AUP projects don’t open any more and there is no escape other than reading the chapter, or the book, again.

Why not just save your MP3 files? Because you can’t edit an MP3 without sound damage and if you do edit a 192-quality MP3 file, it’s not 192-quality any more and you can’t re-submit it.


Thanks, guys - you were absolutely right about the slider so problem solved! I’ve saved WAV files so should be OK for version 3. :smiley: :smiley: