Technical Specifications

 

Quick Tip: If the audiobook passes ACX specs, it will pass ours with the following exceptions: 

  • Room tone length at the tail end of files must be under 3.0 seconds. Even 3.01 seconds will not pass QC. (We recommend 0.75 seconds of room tone at the head of files and 2 seconds at the tail of files.)

  • No extraneous noises, including but not limited to: Rumbling, hisses, noise in the background, split breaths, and excessive mouth clicks.

  • Audiobook files must be labeled as explained below.

AUDIOBOOKS UNLEASHED SPECIFICATIONS 

Labeling:  

All MP3 files should be delivered in one ZIP file, labeled as “ISBN_Title of  Audiobook”.  

Each audiobook file must start with the ISBN, followed by a 3 digit number. Your audiobook will not pass QC if labeled incorrectly. (You can find your ISBN at the top left of your project’s page, next to the title of your audiobook.)  

See these examples:  

The very first file, the Opening Credits, would be labeled as  “ISBN_001”. The first chapter (or other front matter) would be  labeled as “ISBN_002”. The tenth chapter would be labeled as  “ISBN_011”.  

The sample should be labeled as “ISBN_Sample”.  

The cover should be labeled as “ISBN”.  

Need to rename your files? Check out this video: “How to relabel file  names using WinZip in 5 minutes or less” 

Technical Specifications:

*We follow these specifications strictly, so please double check your files or they will be rejected and subject to delays!*

Files must be MP3 files, delivered in one ZIP file.

Chapters may not be longer than 60 minutes.  

Files must be in either all mono or all stereo. (Mono is the standard.)

Constant bit rate of 192 kbps or higher.  

Sample rate of 44.1 kHz.

Recommended maximum noise floor of -60dB.

Peaks below -1db.

  • We recommend… keeping peaks below -3db.

RMS between -24db and -14db RMS.

  • We recommend… normalizing the RMS of all files to -20db. (Be sure to double check the peaks and noise floor are still within specifications.) Ideally, you want the average RMS for the entire audiobook to fall within -21db and -19db RMS.

Files must start and end with room tone – Room tone length must be under 3.0 seconds. (Even 3.01 seconds will not pass QC.)

  • We recommend… having 0.75 seconds of room tone at the head of files and 2 seconds at the tail of files.

No extraneous noises, including but not limited to: Rumbling, hisses, noise in the background, split breaths, and excessive mouth clicks.

 

Credits: 

Each audiobook must have Opening Credits and Closing Credits. 

  • Suggested opening credits only include: Title, Name of Author(s), Name of  Narrator(s).  

Example: “This is Romeo and Juliet, written by William Shakespeare,  narrated by Kate Minola.”  


  • Suggest closing credits include: Title, Name of Author(s), Name of Narrator(s), Copyright (of the manuscript), Production Copyright.  

Example: “This has been Romeo and Juliet, written by William  Shakespeare, narrated by Kate Minola. Copyright 1594 by William  Shakespeare, Production Copyright 2020 by William Shakespeare.”  

Specifications for the Sample: 

A sample of the audiobook should be included and labeled as “Your  ISBN_Sample”.  

Suggested length is 3 – 5 minutes.

No explicit (e.g. violent or pornographic) material is allowed.

Cover Photo:   

We accept JPG or PNG files.  

The cover must show the Title and Author.

  • Narrator names are strongly suggested, but not mandatory. We also suggest adding any Series info, if applicable.

It must be a square – Do not add borders to make your ebook cover a square.

Do not put anything on the cover that looks like a physical product is being bought. (CD cases, physical book covers, toys, etc.)

Please name the cover photo as your ISBN.  

Specifications:  

Preferred: 3000 x 3000 px, 300 dpi, 24-bit color, RGB format only

Minimum: 2400 x 2400 px, 72 dpi, 24-bit color, RGB format only

  • Need help? Use this link to convert your photo to the right specifications. (Your photo must already be a square!)  

Here are the minimum settings you should enter 

A maximum of 10 MB in size 

 

For any technical questions, please email tech@audiobooksunleashed.com. Thank you!



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