More and more outlets support high resolution audio and/or music specifically mastered towards digital distribution in the highest possible subjective and technical quality. 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. Note that delivery of high quality audio is not mandatory.
Requirements:
Same as for Standard Audio, except:
- Bitrate: 24 bit
- Audio container: only .WAV
- Sample rate: 44.1, 48, 88.2, or 96 kHz
Simply up-sampling and/or bit-padding of standard quality 44.1 kHz/16-bit files is not recommended and frankly rather pointless
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
- Preferably 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. Even better, go back to original (if available, high quality analogue) source.
How do I get an ADM badge next to my songs then?
Option 1: become an Apple certified mastering engineer yourself, and you can apply for the badge with tracks mastered by yourself. The application proces involves a questionnaire and a check of your mastering methods, your studio and your equipment. Please refer to the Apple website for more information.
Option 2: have your tracks mastered by an Apple certified mastering engineer. Just ask your mastering studio for their ADM certification.
Option 3: follow the guidelines above yourself, or have your mastering engineer follow them. Then deliver your 24 bit audio to us and we will make sure your audio is ADM compliant, since our in-house audio engineers are Apple certified.