48kbps M4a(-1 B) Page

When M4A files are encoded at low bitrates like 48kbps, they typically utilize . A specific feature of this technology is Spectral Band Replication (SBR) :

: It then includes a small amount of "helper" data that allows the player to reconstruct the high frequencies during playback, simulating a full-range sound. 48kbps m4a(-1 B)

: Instead of trying to encode every high-frequency detail (which would require more data), the encoder only records the lower frequencies. When M4A files are encoded at low bitrates

: You can store roughly four times as much audio compared to a standard 192kbps MP3 while maintaining reasonable intelligibility. 48kbps m4a(-1 B)