GSM vs WV
A detailed comparison of GSM Audio and WavPack Audio — file size, quality, compatibility, and which format to choose for your workflow.
GSM Audio
Audio FilesGSM 06.10 is a speech compression standard designed for the Global System for Mobile Communications. It encodes speech at 13 kbps using Regular Pulse Excitation with Long Term Prediction, optimized for voice intelligibility over cellular networks.
About GSM filesWavPack Audio
Audio FilesWavPack is an open-source audio codec that offers lossless, lossy, and hybrid compression modes. Its unique hybrid mode creates a lossy file plus a correction file that together reconstruct the original, enabling flexible storage strategies.
About WV filesStrengths Comparison
GSM Strengths
- Tiny bitrate (13 kbps) — hours of speech in a few MB.
- Speech-optimized — clear voice reproduction.
- Universal cellphone decoder adoption 1991-2015.
- Stable since 1987.
WV Strengths
- Hybrid lossy/lossless mode.
- Supports DSD, 32-bit float, multichannel.
- Competitive compression vs FLAC.
- Active maintenance since 1998.
Limitations
GSM Limitations
- Speech-only — music sounds distorted.
- 8 kHz sampling — narrowband, muffled by modern standards.
- Legacy — LTE VoLTE moved to AMR-WB, Opus, or EVS.
- Tooling outside telecom is sparse.
WV Limitations
- Small ecosystem.
- Hybrid mode complexity.
- Hardware support limited vs FLAC.
Technical Specifications
| Specification | GSM | WV |
|---|---|---|
| MIME type | audio/gsm | audio/x-wavpack |
| Extension | .gsm | .wv (main), .wvc (correction) |
| Codec | GSM 06.10 (RPE-LTP) | — |
| Sample rate | 8 kHz | — |
| Bitrate | 13 kbps | — |
| Modes | — | Lossless, Hybrid lossy+correction, 32-bit float |
| License | — | BSD-style |
Typical File Sizes
GSM
- 1 min of voice ~100 KB
- 1 hour voicemail archive ~6 MB
WV
- 3-min song (CD lossless) 18-24 MB
- 3-min hi-res 24/96 60-90 MB
Ready to convert?
Convert between GSM and WV online, free, and without installing anything. Encrypted upload, automatic deletion after 2 hours.
Frequently Asked Questions
GSM (GSM Audio) is an audio file format used to store sound recordings — music, voice, podcasts, sound effects. The format defines how the audio samples are compressed (or stored raw), what bitrates are supported, and how metadata such as title, artist, album, and cover art is embedded. It is part of the audio files family.
WV (WavPack Audio) is an audio file format used to store sound recordings — music, voice, podcasts, sound effects. The format defines how the audio samples are compressed (or stored raw), what bitrates are supported, and how metadata such as title, artist, album, and cover art is embedded. It is part of the audio files family.
VLC, foobar2000, and the default media players on Windows and macOS handle GSM natively. On mobile, iOS Music and Android media apps vary in their support — popular formats work everywhere; niche ones may need a dedicated app. If playback fails on a device, converting to MP3 or AAC usually solves it.
VLC, foobar2000, and the default media players on Windows and macOS handle WV natively. On mobile, iOS Music and Android media apps vary in their support — popular formats work everywhere; niche ones may need a dedicated app. If playback fails on a device, converting to MP3 or AAC usually solves it.
Upload the GSM to KaijuConverter and pick MP3, WAV, FLAC, AAC, OGG, or any other target. Our FFmpeg pipeline decodes the audio and re-encodes to the target format at sensible default bitrates (VBR ~190 kbps for music, 96 kbps for speech). Metadata and cover art travel with the audio where both formats support them.
GSM can be lossy or lossless depending on the specific variant. Lossy variants (smaller files) discard some audio detail during compression in ways tuned to be inaudible; lossless variants preserve every sample exactly but produce larger files. For distribution, lossy at high bitrate is standard; for archival, lossless wins.