Audio Converter

Lossy, lossless, and the difference it makes

MP3, AAC and Opus are lossy: they discard information the ear is unlikely to notice, which is why a three-minute song fits in three megabytes. WAV and FLAC are lossless — WAV stores the raw samples and is enormous, FLAC compresses them losslessly to roughly half. A useful rule: going from lossless to lossy is a decision worth making once, carefully; going from one lossy format to another always costs quality and should be avoided unless the target format is genuinely required.

Bitrate is the main dial for lossy formats. 128 kbps is acceptable for casual listening, 192 kbps is transparent for most music, and 256–320 kbps is where further increases stop being audible. There is no benefit to converting a 128 kbps MP3 into a 320 kbps one — the information was already discarded, and the larger file contains the same approximation padded out with bits.

Sample rate, channels and loudness

Sample rate decides the frequency ceiling: 44.1 kHz covers everything a person can hear, and 48 kHz is the video-industry standard to keep audio in sync with picture. Converting upward cannot add detail that was not recorded. Channel count is the more practical lever — collapsing a podcast to mono halves the file and is often indistinguishable through headphones.

Loudness normalisation is the one processing step worth applying on a regular basis. EBU R128 measures perceived loudness rather than peaks, so a quiet interview and a hot mix end up at the same comfortable level instead of forcing you to reach for the volume control. It is the same standard broadcasters use for television.

FAQ