The entry object · one payment, no subscription
Five retailers, every submission spec, read off the retailer’s own page.
A file rejected on a technical spec costs a week and feels like a personal failure. The specs are public, scattered across five help centres, and contradict each other on cover art, file format and synthetic voices. The Spec Pass is that reading, done, dated, with every source printed next to the number.
14 days, no questions, full refund
- Price
- $19, once
- Retailers covered
- 5
- Specs stated at source
- 36
- Rejection triggers, with fixes
- 15
- Delivery
- A web page, immediately
- Updates
- Included, for good
Verified 2 September 2026
Next check due 1 December 2026
What is inside
A spec sheet per retailer
Format, bitrate, sample rate, channels, peak ceiling, RMS window, noise floor, file length, credits, retail sample, cover art and metadata — for Audible/ACX, Spotify, Apple Books, Google Play and Kobo. Where a retailer publishes no number, the sheet says so instead of borrowing one from a blog.
The AI-narration rule, retailer by retailer
Who accepts synthetic narration, who forbids it, and the exact disclosure field or wording each one wants. ACX prohibits unauthorised text-to-speech. Kobo asks you to credit a synthesised voice by name. Spotify has a toggle and edits your description. Apple and Google run their own pipelines instead.
One master that satisfies all five
Eight settings — peak, RMS, noise floor, sample rate, channels, exports to keep, file split and cover art — chosen against the strictest published number on the list, each with the reason it is the one to obey.
The rejection-fix guide
15 documented reasons files come back, each with the retailer that rejects it, the source, and what to change. Written for someone who has never seen a decibel.
A line from the ACX sheet
RMS level: -23 dB to -18 dB per file.
Peak: -3 dB or lower.
Noise floor: -60 dB RMS or lower.
Measured per file, not across the book. The noise floor is the only one of the three you cannot fix after recording.
Buyers get every later revision at no cost. When a retailer moves a spec or changes its disclosure rule, the sheet changes and the date on it changes with it.
What it does not do
- It does not master your files or check them for you. It tells you the numbers to hit and where they came from.
- It is not a plan for your book. It carries no cost estimate, no narrator brief and no timeline — that is the Production Plan, and it is not built yet.
- It is not legal advice, and it is not a contract with any retailer. Specs move; that is why the pass is dated and maintained rather than sold as final.
Who should not buy it
- Anyone paying a producer for a retail-ready file. Your producer is contractually responsible for these specs. Ask them for the measurement report instead.
- Anyone publishing to one retailer only, who has already read that retailer’s page. You would be paying $19 for the four you do not use.
- Anyone still deciding whether to make an audiobook at all. Run the Reckoner first. It is free and asks for no email.
Where the numbers come from
We sell no narration, no production and no distribution, and we take no commission from anyone who does. Nothing in the pass points you toward a service we are paid by.
Buy the Spec Pass — $19Hosted checkout. You land on your permanent link the moment the payment clears, and the desk answers at auralfile@nanocorp.app.