I’m using macOS Big Sur Version 11.6 on my MacBook Air M1 2020.
I’m using Audacity 3.0.5
I mainly use Audacity to produce audiobooks on the ACX website. A sound file has to meet the following ACX requirements to be accepted:
Peak Level: -3.00 dB
RMS Level: between -23 dB and -18 dB
Noise Floor: Max of -60 dB
I have finished entire files, where, upon saving before closing, they meet the ACX requirements. However, in the last two days, upon opening those same files, they fail the Noise Floor requirement. I’m getting the error, "Noise floor: -inf dB Warning (too low - Dead silence sounds unnatural.)
Is anyone encountering this issue? If so, is there a fix or do I have to re-record and edit all over again? This is extremely frustrating.
Thanks for the help.
What’s between our voice and the Air? Are you using the Air’s microphones?
The problem is not so much Blackness of Space Silence sounding unnatural, as what it does to the words. Nobody can actually record dead silence, so there must have been some software tricks, filters, or effects somewhere in the process.
in the last two days, upon opening those same files, they fail the Noise Floor requirement.
What kind of files? You are urged strongly not to do production directly in the MP3 format that ACX needs. Use WAV for production and masters and then make an MP3 copy just before you post to ACX.
But the files don’t all do that?
Do you use Zoom, Skype, Meetings or other chat application? Audacity doesn’t like those very much and the combination can create sound damage.
What are the ACX-Check readings after mastering, but before you exported the files? This is about right.
Thank you to steve and kozikowki for your replies.
Steve: with your tip, I found all the “dead silent” sounds and they were exactly where I edited my inhales out. I used the “silence audio” tool to simply remove the breath sound, rather than replacing it with room tone. Which is what triggered the “-inf dB” warning.
Kozikowski: Your question of the ACX Check before and after mastering was dead on. I was only doing the ACX Check immediately after recording audio (my narration) and just assumed it would continue to meet the ACX Check after mastering. But no - as mentioned above, when I silenced my breath sounds, it triggered the “-inf dB” warning for the Noise Floor.
Also, I master the project as an audacity file (.aup3) until the mastering is complete, and only then to I export it as an .mp3 to upload it to ACX.
I’ve learned my lessons:
Replace breath sounds (and other sounds needing to be edited out) with room tone rather than the silencer tool.
Run the ACX Check again (and probably throughout) after mastering to ensure the file continues to meet ACX requirements.
I used the “silence audio” tool to simply remove the breath sound, rather than replacing it with room tone. Which is what triggered the “-inf dB” warning.
You may be the test case for the Punch tools. There is a series of tools in the Punch group that are designed for this kind of job. They will watch your selection of work (select the damage) and custom tailor a replacement (assuming you have replacement matching Room Tone) to exactly fit.
One of the variations is to fade in and out of the repair making it less obvious what you did.
I know about them but have 0.00 experience with actually using them. This is odd because extra noises in my voice recording is exactly what caused my audiobook rejection. So tag, you’re it.