I'm looking for a program that can convert audio files from NIST sphere format (SPH) to WAV.

Any license, operating system and price is fine.

I tried SoX (Sound eXchange) (free, CLI, Linux):

sudo apt-get install -y sox
sox file.sph file.wav

but with some files (e.g., WSJ speech recognition corpus) I did the message:

sph: unsupported coding `pcm,embedded-shorten-v1.1'

1 Answer 1


You can use sph2pipe_v2.5 (mirror):

  • Free
  • open source
  • Linux, Mac OS X , Microsoft Windows

To use it on Microsoft Windows:

sph2pipe.exe file.sph file.wav

To compile on Linux (from the readme provided with the program):

gcc -o sph2pipe *.c -lm

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.