Hi, I’m uploading mp3s to ACX.com and they said this message: File is encoded at an incorrect sample rate. Re-encode the original source audio to 44.1kHz
I went to Audacity, hit track > resample > changed it to 41000 and saved the file but ACX.com then said it was not changed. I went back to Audacity, checked the mp3 and it’s auto reverted back to 48000. Each time I edit it to 41000 and save the file, when I check Audacity, it’s again taken the mp3 to 48000.
What do I do to fix this or is this an Audacity technical/bug error? Thanks.
Yes. So your file will be exported at the sample rate specified in Audio Setup > Audio Setup > Quality > Project Sample Rate.
Yes, you correct. This is confusing. The developers have been working on a solution to the issue which should be included in the next release of Audacity.
Thanks for the quick response. So that means I can’t get the audiobook live until Audacity fix this? Or are there alternative websites that it’ll convert to 41000 correctly?
No, what @jademan is telling you is to change you Project Sample Rate to 44100 Hz.
To do this
either go to
a) Preferences> > Audio Settings or
b) Click on the Audio Setup button in the top tooldock and choose Audio Settings from the menu
Change the Project Sample Rate to 44100 Hz
and while you are there also make sure the Default Sample Rate is set to 44100 Hz
Then make the export.
In the upcoming 3.4.0 version of Audacity things become easier in this regard as the new export dialog will have a parameter enabling you to set the sample rate of the export at export time.
Peter, Thank you for translating.
Amazing - it worked. Thank you both SO much!!
So I have another topic question - not sure if I need to write a new post but since you two have been spot on, I thought I’d run this by you. It’s the last audio I’m constantly being rejected for:
RMS is too low. Raise the level of this file 1.6 dB. It’s currently -24.6. I go to effect > volume/compression > loudness normalization and edit it to anywhere between -20 and -18db. But then when I reupload the file to ACX, it says my db is 0 and so I go back to effect > volume/compression > normalize and change it to -0.3db, export, upload to ACX and then it says my RMS is too low. I can’t seem to find the solution to this - either RMS is correct and db isn’t or vice versa. Any genius answers please?
Yes, you are correct. In the meantime, perhaps @kozikowski will see this and can offer some input.
Audacity publishes Audiobook Mastering Macro, which is a collection of tools that, when applied to a chapter, guarantees RMS (Loudness) and Peak (tips of the blue waves). If you recorded in a quiet, echo-free environment (studio) that may be all you need.
I have a question. ACX used to offer analysis for a sample posting or short chapter. That’s back when I did it. They stopped doing that and the only option is post a whole book and hope for the best. Did they reject your whole book?
There is an odd problem with MP3. You can’t fix or modify them without affecting the sound quality. ACX demands MP3 quality of 192-Constant for submissions. If you patch or correct your submitted files, they’re not at 192 any more, even though that’s what the export panel says.
What’s supposed to happen is you produce WAV Edit Masters of all your chapters, then burn the MP3s for submission to ACX from those WAVmasters. If you have to change anything, change the WAVs and then make whole new MP3s.
There are other New User mistakes. One forum poster was trying to record their whole book as one sound file. Don’t do that.
Hi, so I uploaded about 60 audios that someone recorded - he’s since passed away. Each one is a chapter of an already published book on Amazon. All the audios are approved aside this specific one. It is 192kb. And db is -0.3 but the rms is the problem when I apply the db. And when I fix the rms, the db is then the problem. What do you suggest please?
I suggest applying our Audiobook Mastering Macro which guarantees both RMS (Loudness) and Peak (dB) at the same time.
There can be a problem. That one chapter may, in some small way, not match the others. ACX hates that.
Do you have a safety backup of that one chapter in case anything messy happens?
I need to go into the spells and see if there’s a way to minimize sound changes while still forcing conformance.
As we go.
This is a graphic version of the individual tools called in the Macro.
Do Not apply the first tool, Filter Curve. Do apply the second and third tools. Can you follow the settings?
Thank you and yes, I have a back up and should understand the settings/instructions. I’ll update you when I’ve uploaded the audio tonight or tomorrow eve. Thank you SO much!
Unreal - I tried so many ways but it didn’t work. I followed your instructions and it worked. Now waiting for final approval. Thank you SO much, beyond words!!!
Those yellow words up in that graphic represent the three steps that were built into Audiobook Mastering. Seems simple doesn’t it?
Normally, we urge strongly not to break up the steps, add any, or leave any out. The steps depend on each other and clean up after each other. There is an overarching goal of not affecting the sound of the performance—the chapter starts working and nobody can tell what you did. So this normally sails right past ACX quality control.
Yes, it was so strange that it worked. I usually edited audios in ‘effect’ and it kept failing, yet your solution was the winning ticket! Massive fingers crossed all is approved - we’re just waiting to hear back now after submitting. Thank you!!!