What FLAC adds, and what it does not
FLAC is a lossless compressed format. It keeps every sample of the audio it receives, in a file roughly half the size of a WAV. When you convert M4R to FLAC, you get a perfect copy of the decoded ringtone. What you do not get is more quality: the AAC inside the M4R is lossy, and whatever its encoder removed stays removed.
When this conversion is useful
- An archive in one format. If you keep all your sounds in FLAC, converted tones fit in without exceptions.
- Repeated editing. A FLAC working copy can be opened, changed and saved many times without new compression damage.
- Players and systems that prefer FLAC. Some music servers, hi-fi streamers and Linux setups handle FLAC better than AAC.
If you simply want the tone to play on another phone, M4R to MP3 is the better choice; it is smaller and works everywhere.
Size and settings
| Version of a 30-second tone | Approximate size |
|---|---|
| M4R, 256 kbps | 1 MB |
| FLAC, 16-bit, 44.1 kHz | 2.5–3.5 MB |
| WAV, 16-bit, 44.1 kHz | 5.3 MB |
Keep 16-bit and the original sample rate, usually 44.1 kHz. A 24-bit FLAC from an AAC source is only worth it if you plan strong processing. The FLAC compression level changes speed and size, never the sound.
Tags
FLAC stores metadata as Vorbis comments. Any title or artist stored in the ringtone is copied across where possible, so the tone keeps its name in your library. Many tones made in GarageBand or ringtone apps carry no tags at all, so check the file name before you archive it.
If you want to know whether a FLAC file came from a lossy source, view it in the spectrum analyzer: AAC tones usually show a clear upper limit around 16–20 kHz. To make an edited FLAC into a ringtone again, use FLAC to M4R.