ACX Check plugin - region

I’ve been doing a SELECT ALL when running my ACX Check plugin.

But It appears this is not needed?

Perhaps I only need to select the first 5 minutes of the track to get a good indication about if i’m ok or not…?

I ask because i’m not completely sure how this plugin works, nor what it’s looking for.
I’d prefer to only test a portion of my audiotrack, because then the process completes much faster.

What do you guys think?

Select the first 5 minutes or select the whole thing?


If you run ACX Check after AudioBook Mastering, then the first five minutes is probably OK. Mastering makes everything match. If you’re trying to read directly into audio book specifications or using another protocol, then you have no choice. Any voice variation anywhere in the performance may violate ACX technical testing and get flagged.

One of the tools is only good for 37 minutes and I forget which. So long chapters is Not Good.


nor what it’s looking for.

ACX publishes technical specifications for audiobook sound submission. There’s only three: overload protection (Peak), loudness (RMS) and background noise volume.

That would seem simple but everybody fails noise because the specification means your background noise (room tone) has to be 1000 times quieter than your voice. Nobody can meet that in the average home or apartment. We’re all living in noise bubbles.


That’s true

i am running the plugin AFTER doing all the other processes here

Thus, of the 3 checks, (overload protection (Peak), loudness (RMS) and background noise volume) I guess that, after I run the stack of 3 processes, I don’t think it’d be possible for my track to have overload or loundness anyway.

So only background noise would be left.

In theory, some parts of my track would have more background noise than others, so if i only check the first 5 minutes, then (i theory) i might miss a bit of noise at the end. Which i didnt catch for some reason during “noise removal”


ACX is expecting the Room Tone at the beginning and end to match and the background noise not to wander during the performance. That’s one reason our AudioBook Mastering, if that’s the one you used, doesn’t have a compressor in it. Compressors create problems.

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ACX Check is not reliable during a spoken performance. It depends on at least 3/4 second of pure, clean background noise (Room Tone) to work right. Even if someone theatrically pauses for that long, they will be breathing heavily in that time and give a silly high (invalid) noise reading.

In theory, some parts of my track would have more background noise than others,

If you announce by walking around the room with a portable microphone, then yes. But if you have a stable recording environment, you should be able to crank out page after page with little or no background variation.

6dB volume change, in English, means half and double. That’s very serious sound change. Even if you have to set up a portable studio each time you announce, make sure your recording settings are the same and your spacing is about right, and that should work.

You should know that recording on a Windows machine can be an exercise. Data Errors with clicks and pops, forced Internal Sound Processing, Game and Skype fights, Sound routing errors and Virus Conflicts. That’s the short list. About the second or third week of fighting with your computer, it is recommended you stop using it to record. Record on a stand-alone sound recorder.