Audiobook Mastering Guides for Narrators
A library of 8 technical guides on ACX audiobook submission, rejection fixes, and post-production workflows, written for narrators and indie authors.
Most popular guides
If you are new or recovering from a rejection, these three articles cover the shortest path.
ACX Audio Specs + Fix Your File Free (2026)
May 29, 2026
The eight exact specs your files must hit to pass.
ACX Rejected Your Audiobook? Fix Every Issue
May 20, 2026
Decision tree from failure email to the precise fix.
Audacity Audiobook Mastering: Full ACX Workflow
May 20, 2026
Step-by-step effect chain for home studios.
ACX Technical Specs and Rejection Fixes
Master the technical thresholds of the submission process and turn rejection emails into deterministic fixes.
ACX Rejection Email Decoder: Understand and Fix the Failures
May 20, 2026
Translate confusing ACX rejection emails into deterministic fixes. Learn why your audiobook failed for loudness, true peak, or noise floor, and exactly how to repair it.
ACX Submission Checklist: Prepare Your Audiobook for Approval
May 20, 2026
The complete step-by-step checklist to prepare, master, and format your audiobook files for ACX submission. Pass the automated analysis on your first try.
ACX Audio Specs + Fix Your File Free (2026)
May 29, 2026
The exact ACX targets for RMS, peak and noise floor, plus a free in-browser way to master your file so it passes on the first try.
ACX Rejected Your Audiobook? Fix Every Issue
May 20, 2026
From ACX rejection email to fix, without uploading your file. Loudness, noise floor, true peak, format. Files stay in your browser.
Audiobook Noise Floor: What It Is and How to Fix It
May 20, 2026
Why boosting loudness pushes the noise floor above ACX's -60 dBFS and why gating works where noise reduction fails.
Mastering Tools, Workflows, and Practical Setup
Understand the software side of producing clean, spec-compliant audiobook audio in a home booth.
Audacity Audiobook Mastering: Full ACX Workflow
May 20, 2026
The exact Audacity effect chain for mastering audiobooks to ACX spec. Noise reduction, compressor, normalise, limiter, and the batch macro.
Best Audiobook Mastering Tools Compared: 2026 Guide
May 20, 2026
Honest comparison of Audacity, Auphonic, Hindenburg Narrator, Source, and ChapterPass for ACX audiobook mastering. Features, pricing, trade-offs.
What ChapterPass Does (and What It Does Not)
May 20, 2026
ChapterPass masters audiobook files to ACX spec in your browser. No account. Files never uploaded. First file free. Honest scope and what it does not do.
A library built for the narrator in the chair
These guides are for the person who records the book, masters the files, and submits them. Independent narrators working from a home booth. Indie authors doing their own ACX submission. Small studios that handle a handful of titles a year rather than a slate of fifty. If you run a full post-production house, most of this will be familiar. If you are anyone else, this is where you start.
Every article answers a question a real narrator has asked us, usually after a rejection email or a failed upload. The point is not to teach audio engineering from first principles. The point is to get your chapter through ACX's automated check and onto a listener's phone, with the voice intact.
More guides will join these as questions repeat in our inbox. If there is something you want covered and cannot find here, get in touch.
Ready to test your audio? Run your first file through the Free ACX Check.