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Table Of Contents
Chapter 21 Share projects 724
M4A: AAC bounce options
When you click M4A: AAC in the Destination area of the Bounce dialog, the following options are
available:
Encoding pop-up menu: Choose Advanced Audio Codec (AAC) or Apple Lossless to set the
encoding for your .m4a (commonly referred to as MP4) le. While both encoding algorithms
provide high-quality audio, the AAC format uses a higher compression ratio, resulting in
smaller le sizes.
Choosing the M4A: AAC option in the Destination area disables PCM > Surround. Split Stereo is
still available.
If the selected sample rate is higher than 48 kHz, a copy of the bounced PCM le is created
(with an automatic sample rate conversion to 48 kHz) before encoding. This conversion takes
place because the M4A: AAC format does not support sampling rates higher than 48 kHz.
Bit Rate pop-up menu: Choose a rate between 16 kbps and 320 kbps.
Note: This parameter is only available when the AAC codec is chosen.
“Encode with variable bit rate (VBR)” checkbox: Variable Bit Rate encoding compresses simpler
passages more heavily than passages that are (more) harmonically rich, generally resulting in
better quality les.
Because not all media players can accurately decode VBR-encoded les, this option is o by
default. If you know that your target listeners can decode VBR-encoded les, you can turn this
option on.