Apple Releases Mastering For iTunes Guidelines & Utilities
Apple has released their own specifications on mastering audio files for optimal sound quality in iTunes. There has been a debate over the years between Mastering Engineers whether or not you should master audio separately for digital formats. Some suggested that you should, while others believed that a solid master would work in all formats.
Well, Apple has now chimed in with their own opinion and several of their suggestions should put the debate to rest, or at least to bed for a while. Some of the more intriguing guidelines include not crushing your mix with massive limiting/compression leaving no dynamic range, as well leaving a dB or two of headroom.
Don’t dumb down your files when sending them off to Apple for encoding. If you recorded in 24 bit / 96 kHz, then send that file. Don’t reduce the bit depth and resolution.
Apple includes four free utilities to help you achieve the best possible translation. Master for iTunes Droplet, afconvert, afclip and AURoundTripAAC Audio Unit.