Silence and simple sounds don’t need high bitrates. VBR respects this, saving storage for the moments that truly require data. This was critical in the early 2000s when portable MP3 players had only 128MB or 256MB of storage.
: During silent or simple passages (like a lone voice), the encoder uses fewer bits. When the music becomes complex—such as during a full orchestral swell—the bitrate increases (up to 320 kbps) to preserve intricate details. Vbr Mp3 World