Audiobook production demands a different discipline than music recording or general voiceover. A narrator may spend three to five hours in the booth per session, delivering thousands of words that need to sound consistent from the first chapter to the last. At MIX Recording Studio in Los Angeles, we record audiobooks for authors and publishers distributing through ACX, Audible, and other platforms. Our rooms and signal chain are built for the level of acoustic isolation and vocal clarity that ACX requires, and our engineers handle the technical compliance so you can focus on the performance.

If your project is a commercial voiceover, e-learning narration, or character demo reel rather than a long-form audiobook, our voiceover recording page covers those workflows. This page is specifically about audiobook and ACX production.

ACX enforces a strict set of audio specifications that every submitted file must pass before it reaches Audible listeners. Peak levels must stay at or below -3dB. The RMS level for each file needs to land between -23dB and -18dB. The noise floor must measure below -60dB. Files are delivered as 192kbps CBR MP3 at a 44.1kHz sample rate, mono, with each chapter as a separate file. Every file must include a half-second to one second of room tone at the head and tail.

These requirements are not arbitrary. They exist so that listeners on earbuds, car speakers, and home systems all hear a consistent, clean signal without jumps in volume between chapters or background hiss creeping in during quiet passages. The vocal booth at MIX has a noise floor well below the -60dB threshold, which means we are not fighting the room during recording. The acoustic treatment keeps reflections tight and controlled, giving the mastering stage a clean source to work with rather than a signal buried in room coloration.

Long-form narration rewards a microphone that stays smooth across hours of use without fatiguing the listener. We record ACX projects through the Neumann U87 or Neumann TLM103, both large-diaphragm condensers with the detailed, even response that translates well to spoken word. The signal runs through a Universal Audio Apollo 8 or Apollo x8 interface with the Empirical Labs EL8X Distressor providing gentle dynamics control. The Distressor keeps the vocal level consistent across chapters without squashing the narrator's natural dynamics, which is critical when a performance shifts between dialogue, exposition, and whispered passages.

On the software side, we record in Pro Tools and Logic Pro X. Mastering uses iZotope Ozone 9 for final loudness targeting and limiting, and FabFilter Pro-Q 3 for surgical EQ work on proximity buildup or sibilance. If your book involves multiple narrators or character voices that need tight timing alignment, Synchro Arts VocAlign handles that. Monitoring in the control room runs through Yamaha NS10, Dynaudio LYD 8, and a KRK 10S subwoofer. The full inventory of available hardware and software is on the gear list page.

A typical ACX session at MIX runs three to five hours. We start with a mic check and level set, adjusting the Distressor ratio and the preamp gain to match the narrator's delivery style and volume. Once levels are locked, we record using punch-and-roll in Pro Tools: the narrator reads until a mistake happens, the engineer rolls back a few seconds, and the narrator picks up cleanly from the last good phrase. This method produces a nearly finished edit in real time, which saves hours of post-production compared to recording straight through and editing later.

Sessions are organized chapter by chapter. Each chapter gets its own Pro Tools session file so the final exports map directly to ACX's per-chapter delivery format. Between chapters, we check levels and review any sections the narrator wants to re-record. After the session, our engineers handle noise reduction, breath cleanup, RMS normalization, and the final MP3 export to ACX spec. We run the finished files through ACX's automated quality check before delivery so there are no rejection surprises on your end.

ACX sessions are booked at our standard studio rates. Daytime recording in MIX II starts at $55 per hour with a two-hour minimum. Sessions of four or more hours Monday through Wednesday or six or more hours Thursday through Sunday drop to $49 per hour. Overnight sessions (midnight to 9 AM) start at $16 per hour Monday through Wednesday and $20 per hour Thursday through Sunday. Sessions with an Advanced Engineer are $79 per hour all-in at the standard daytime rate, and sessions with an Elite Engineer are $89 per hour all-in. Longer and overnight bookings receive reduced engineer rates.

For authors who also make music, our online service at online.mixrecordingstudio.com masters songs for $70 per song with one revision included. Full pricing for all rooms, session lengths, and engineer tiers is on the pricing page.

MIX Recording Studio is at 539 S Rampart Blvd, Los Angeles, CA 90057, in the Westlake neighborhood. We are minutes from Koreatown, Downtown LA, and Hollywood. The building has on-site parking for clients. We are open 24 hours a day, 7 days a week.

Call (323) 218-7475 to discuss your audiobook project or book directly online.