Compare
Vespertine and Cog, compared.
Both are free, open-source players that play FLAC and DSD, local surround files and Apple Spatial Audio, with automatic rate switching and exclusive mode. Vespertine adds SACD ISO images, hi-res file analysis and room correction; Cog streams internet radio. Vespertine does not claim to be the only player offering Apple Spatial Audio for local surround.
Compared from each player’s own documentation or source code. “Not documented” means the vendor doesn’t say either way, not that the feature is missing. Table last updated 29 October 2026; its cells were checked 9 to 14 October 2026.
Feature by feature
The table.
| Feature | Vespertine | Cog |
|---|---|---|
| Source code | GPL-3.0 | GPL-2.0 |
| FLAC / DSD files | Yes / Yes | Yes / Yes |
| Automatic DAC rate switching | Yes | Yes |
| Exclusive (hog) mode | Yes | Yes |
| 16/24-bit PCM without sample changes | Conditions + tests | In-app indicator |
| Local surround files | Yes² | Yes |
| Apple Spatial Audio for local surround | Yes | Yes |
| Hi-res file analysis | Yes | No (live spectrum only) |
| SACD ISO | Yes | No |
| Room correction | Measured in the app (USB mic), or REW / APO and impulse-response import | No |
| Convolution / audio effect plugins | Yes (room correction) / No | No / No |
| Streaming services | No | No (internet radio) |
² Multichannel DAC output and receiver bitstream are experimental, untested on real receivers and multichannel USB DACs (one Sony TV over HDMI has been tested: see docs/DEVICES.md); reports wanted.
Which one
Which to choose.
Choose Cog if…
- You want a GPL-2.0 open-source player that plays internet radio (HTTP and HLS streams) and, like Vespertine, covers FLAC, DSD, local surround and Apple Spatial Audio.
- You want an in-app bit-perfect indicator: Cog reports each track as bit perfect, modified or unknown.
Choose Vespertine if…
- You want SACD ISO images: no Cog decoder reads .iso files.
- You want hi-res file analysis: Cog has a live spectrum display, not an analysis of the file.
- You want room correction measured in the app, or REW / Equalizer APO filter import.
Vespertine is free and open source (GPL-3.0). Price isn’t part of this comparison, and sound quality isn’t ranked.
Sources
Where this comes from.
- Cog
- Cog README
- Comparison sources and scope (docs/COMPARISON.md in the repository): the full list and what was checked.
A documented feature is not a Vespertine hardware test of Cog. Something wrong or out of date? Open an issue and it will be corrected.
More
Other comparisons.
- All comparisons
- Vespertine and Audirvana Studio / Origin
- Vespertine and Roon
- Vespertine and Colibri
- Vespertine and foobar2000 for Mac
- Vespertine and Apple Music (Mac)
- Vespertine as a hi-res audio player for Mac
Vespertine 0.15.1 is free, signed and notarized.
Download for Mac