Please note that delivery of high quality audio is not mandatory. However, some DSPs support high resolution audio. iTunes, and Apple Music in particular, is pushing towards high quality audio with their Apple Digital Masters (ADM) badge, formerly known - and still referred to - as Mastered for iTunes (MFiT). We recommend iTunes’ guidelines as best practice for generating high quality audio in general.
High Quality Audio Delivery Requirements:
Same as for Standard Audio, except:
- Bitrate: 24 bit
- Audio container: only .WAV
- Sample rate: 44.1, 48, 88.2, or 96 kHz
Up-sampling and/or bit-padding of standard quality 44.1 kHz/16-bit files is not recommended and files could be rejected.
Best practice for generating high quality audio:
- During mastering, audition audio as encoded. Apple provides a number of software solutions for this free of charge, such as the stand-alone "Master for iTunes Droplet" or the "RoundTripAAC" plug-in for Digital Audio Workstations. Alternatively, use Sonnox "Pro-Codec V2" plug-in with Apple's "iTunes +" AAC CODEC. Use these tools to set an appropriate level so that the encode doesn't show clipping.
- Avoid digital clipping entirely.
- It is preferable to export the audio from the production in its native resolution (albeit with a fixed requirement of 24 bits).
- Do not repurpose tracks specifically created at CD resolution. If that is the only available source, up-convert before re-mastering and auditioning as encoded. If available, it is preferable to go back to the original (if available, high quality analogue) source.
There are three ways to obtain an ADM badge next to your songs
1: If you have the relevant experience, you can apply to become an Apple certified mastering engineer. The application process involves a questionnaire and a check of your mastering methods, your studio and your equipment. Please refer to the Apple website for more information.
2: You can have your tracks mastered by an Apple certified mastering engineer. Just ask your mastering studio for their ADM certification.
3: Follow the guidelines above (or have your mastering engineer follow them) and send your 24 bit audio to us and we will make sure your audio is ADM compliant as our in-house audio engineers are Apple certified.