WMA to CVS Converter

Encode WMA as CVSD voice modulation audio format

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Voice Coding Format

CVS produces CVSD modulation from WMA — for telephony systems.

Server Processing

No codec libraries needed — convert WMA to CVS online.

Rapid Encoding

Voice format conversion finishes quickly.

How to convert WMA to CVS

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose cvs or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your cvs file right afterwards

About formats

WMA (Windows Media Audio) is a family of proprietary audio codecs developed by Microsoft and first released in 1999 as part of the Windows Media framework. Created to compete with MP3 and AAC, WMA Standard uses perceptual coding to deliver what Microsoft claimed was near-CD quality at bitrates as low as 64 kbps — roughly half the data rate MP3 typically needed for comparable results. The codec family grew to include WMA Professional for surround sound and high-resolution audio, WMA Lossless for bit-perfect archival compression, and WMA Voice optimized for spoken content at very low bitrates. Deep integration with Windows, Windows Media Player, and the Zune ecosystem gave WMA a strong distribution advantage throughout the 2000s, and digital rights management (DRM) support made it attractive to online music stores of that era. Encoding and decoding are handled natively by Windows, requiring no third-party software for playback on any Windows machine. Cross-platform support has improved through libraries like FFmpeg and GStreamer, though WMA remains less universally compatible than MP3 or AAC on non-Microsoft devices. The format still appears in legacy media libraries, though newer codecs have largely taken its place for streaming and portable use.
Initial release: 1999
CVS is a telephony audio encoding based on Continuously Variable Slope Delta modulation, representing voice through a 1-bit delta scheme where step size adapts to track input amplitude. Developed within CCITT (now ITU-T) standards during the 1970s, CVS encodes by comparing each sample to the previous one and outputting a single bit — up or down — with slope magnitude adjusting based on recent bit patterns. This yields extremely low bit rates, typically 16 kbps at 8 kHz sampling, efficient for narrowband voice over constrained channels. CVS files store signed delta-encoded data and are commonly processed using tools like SoX. A significant advantage is bandwidth economy: the 1-bit-per-sample approach demands minimal transmission capacity, essential for military radio links and early digital telephone infrastructure. The adaptive slope mechanism also prevents overload distortion on rapidly changing signals while keeping granular noise acceptable during quiet passages. Though modern wideband codecs have superseded CVS, it retains historical importance and niche utility in legacy telephony and embedded communication devices.
Developer: CCITT / ITU-T
Initial release: 1970

Frequently Asked Questions

Why convert WMA to CVS?

CVS employs Continuously Variable Slope Delta modulation, standard in telephony and military voice channels. These systems have no WMA decoder, so conversion is the only path.

Which devices and software use CVS files?

CVSD-based military radios, legacy telephony equipment, and SoX on desktop platforms all consume CVS audio. It is a niche format outside of those specialized environments.

Is CVS suitable for music or high-fidelity audio?

No — CVSD is strictly a voice codec optimized for speech intelligibility at very low bitrates. Music or ambient sounds will lose most of their detail in conversion.

Can I adjust encoding parameters when converting WMA to CVS?

Convertio applies the standard CVSD modulation settings suited for telephony voice channels. The output is optimized for speech clarity on the target hardware.

Can I process multiple WMA files to CVS in one session?

Yes — upload a batch of WMA recordings and Convertio encodes each one to CVS simultaneously. Download the results individually or as a combined archive.

WMA to CVS Quality Rating

5.0 (2 votes)
You need to convert and download at least 1 file to provide feedback!