OCTAV
Support
OCTAV is a sound engineering toolkit for iPhone and iPad: tone generation, chromatic and drum tuning, a calibrated SPL meter, a 31-band analyser with feedback detection, and a learning section for training your ear.
CONTACT
Email: [email protected]
We reply within 10 business days.
When reporting a problem, please include your device model, your iOS version, the OCTAV version (Settings > About), and what you were doing when it happened.
REQUIREMENTS
iPhone or iPad running iOS 18 or later. Microphone access is required for the tuner, meter, and analyser.
COMMON QUESTIONS
RECOMMENDED MICROPHONE
Dayton Audio iMM-6C Calibrated Measurement Microphone
For accurate SPL readings and frequency analysis, we recommend the Dayton Audio iMM-6C. It's a USB-C calibrated measurement microphone designed for both Android and Apple devices. Each unit ships with an individual calibration file that corrects for its specific frequency response, giving you measurement-grade accuracy that a phone mic simply cannot match.
Calibration Setup
Each iMM-6C has a unique serial number printed on the microphone body. You'll use this to download a calibration file specific to your unit, then load it into OCTAV so the app can correct for your mic's individual frequency response.
Find your serial number
Look on the microphone body for a number starting with "cmm" (e.g. cmm34621).
Download your calibration file
Go to the Dayton Audio Calibration Tool, select "iMM-6" as the microphone type, enter your serial number, and download the .txt file.
Load the file into OCTAV
Open OCTAV, go to Settings, tap "Load Calibration File," and select the .txt file you downloaded. The app will apply the correction curve automatically.
Verify
With the mic connected and calibration loaded, your meter and analyser readings will now reflect measurement-grade accuracy. The calibration is saved and persists between sessions.
Tip: If you already use the built-in meter calibration offset, reset it to 0 after loading the external mic's calibration file — the file handles the correction for you.