Retail-ready audiobooks. You direct every sentence.
Stop failing ACX. Stop paying $3k+ for a narrator. Stop hearing your character voices drift between chapters 4 and 14. SpeechSyn is the audiobook stack for creators recording on consumer hardware (laptop, USB mic, untreated room). Free ACX and Apple Books QC, retail-ready mastering, and (soon) cast voices for every character with one-click regenerate per sentence.
- Pass ACX on the first try
- Direct every sentence
- Tuned by real audiobook creators
- Book 2 starts where book 1 finished
Ready when you are
Click below and speak normally for five seconds. We listen for your room noise between words, how far your voice sits above it, your loudest peaks, and any distortion. ACX, Apple Books, and Spotify Audiobooks check those on every submission. Runs entirely in your browser with no signup required.
Already recorded a chapter? Drop in a WAV, MP3, M4A, MP4, or OGG, up to two hours, and we'll run the same checks. It's analysed in your browser and never uploaded.
Help us build the audiobook tools you actually need.
We're a two-person team building for audiobook creators the big platforms overlook: indie authors, author-narrators, laptop narrators, self-publishers, and small presses recording on consumer hardware. Tell us what your last book cost you, what kept you from shipping one, and what would make you hit publish this year. Your answers shape what we ship next.
- Priority early access
- Direct roadmap influence
- Free tier plus discounted Studio mode
Six things that make or break an audiobook (measured, fixable, yours).
Every capability is tuned for long-form audiobook production, for creators recording at home on consumer hardware, for authors producing in their own cast voice, and for the exact rules ACX, Apple Books, and Spotify Audiobooks actually enforce.
Pass ACX on the first try
Listen to your room and your voice for five seconds. We tell you what's working, what isn't, and exactly what to fix: the loudest peaks, your speaking level, room noise between words, any distortion. Every check carries the platform rule and the next concrete action, never just a number.
Catch the chapter where your gain drifted
Drop each chapter in and get a per-file pass/fail against ACX, Apple Books, and Spotify Audiobooks, plus a benchmark against professionally produced audiobooks in your genre. Specific fix per chapter, no guesswork on which one to redo.
Hear what your listeners will hear
Each chapter gets a producer's note: one paragraph, plain English, plus one to three concrete next actions. Run the de-noise pass. Try a re-take from 0:42. Ready to submit. The verdict is the product, not a stack of scores.
Closet booth → retail master
Turn raw home recordings into retail-ready narration. De-noise, de-hum, replace bedroom room tone with studio tone, and restore the high frequencies a consumer mic loses, without the AI smear that gets audiobooks rejected.
Book 2 starts where book 1 finished
Cast voices, IPA pronunciations, mastering presets, and character samples: saved to your account once and reused on every book in the series. Don't re-teach the system how to say your protagonist's name when you start the sequel. Don't recast your villain. Don't redial your master.
Fix one sentence, not the chapter
Generate the whole book, then walk it line by line. Mispronounced character name? Wrong voice on the antagonist? Off-tone climax? Re-render that one line (same voice, same room tone, same book) without re-tracking the chapter. You direct every sentence. Each correction tunes the next version of the SpeechSyn model, unless you opt out in Settings.
From recording setup to finished audiobook.
Each tool plugs into the stage of production where audiobook creators lose the most time and money · starting with a free browser check that stops an ACX rejection before it happens.
- Step 01
Listen to your room first (free)
Run Mic Test before your next session. We listen to your room and your voice for five seconds and tell you what to fix. Every check carries the platform rule and the next concrete action, back off the mic about four inches, treat that reflection, your booth is ready.
- Step 02
QC every chapter before you ship
Drop a chapter into Studio. Get a per-file pass or fail against ACX, Apple Books, and Spotify Audiobooks, and a producer's note on top, in plain English, with one to three concrete next actions per chapter. Benchmarked against professionally produced audiobooks in your genre.
- Step 03
Rescue home recordings
Rescue takes you thought were unusable. Speech enhancement, bandwidth restoration, and room-tone cleanup turn home recordings into retail-ready narration, without the AI sheen.
- Step 04
Cast, direct, save for book 2
When Casting & Direction ships: cast a voice per character, pin pronunciations for invented names, walk through every sentence with one-click regenerate. Each cast voice, pronunciation, and preset carries forward, book 2 starts where book 1 finished, no retraining.
Generating a book is not producing a book.
If ElevenLabs is “generate a book,” SpeechSyn is “produce a book.” Every line the AI renders can be inspected, re-voiced, re-emphasized, or swapped. You direct every sentence.
Fix one sentence, not the chapter
Every line is a re-render, not a re-record. Mispronounced character name at 38:12? Wrong voice at 14:05? Off-tone climax? Re-render that line: same voice, same room: without re-tracking the chapter.
Tuned by real audiobook creators
Every sentence creators flag, regenerate, or re-voice teaches the next version of the SpeechSyn model what audiobook listeners actually expect: long-form rhythm, character voicing, the way invented names get said. Generic TTS doesn't get those right. Opt out anytime.
Book 2 starts where book 1 finished
Cast voices, pronunciations, mastering presets, and character samples: saved once and reused on every book in the series. Don't recast your villain for the sequel. Don't re-pin your protagonist's pronunciation. Move platforms and you start over.
Three tools to produce a book. One workflow.
Mic Test is live today, free, and built to catch an ACX rejection before you hit submit. Studio ships next: chapter QC, enhancement, mastering, and a producer's note per chapter that tells you what to fix. Then Casting & Direction: cast voices for every character, pin pronunciations for invented names, regenerate any sentence in one click. Waitlist members help us shape what ships first.
Mic Test
Five seconds, free, in your browser. We listen to your room and your voice and tell you what to fix · with the platform rule and the next concrete action on every check.
Studio
Upload a chapter, get a retail-ready master. Per-chapter QC for ACX, Apple Books, and Spotify Audiobooks. A producer's note per chapter that tells you what to fix in plain English. Speech enhancement, bandwidth restoration, and 192 kbps CBR MP3 mastering at 44.1 kHz.
Casting & Direction
Cast voices for every character. Pin pronunciations for invented names with IPA. Walk through the book sentence by sentence and regenerate any line in one click · same voice, same room, calmer or sharper or slower. You direct every sentence.