In this project, a perfect PCM sine wave is one that contains a single frequency at 0 dBTP and no error harmonics at all. A bit-perfect PCM sine wave has error harmonics due to encoding quantization, but they are at the minimum level possible for the chosen encoding.
The generated wave files hold a sequence of one or more complete copies of a repeating pattern. A file containing a single pattern can be played in a loop to extend the play time. Because most audio players don't loop cleanly, the included wave files contain enough complete patterns to play 2 minutes without looping.
Every sinusoid in the file contains a whole number of cycles. This ensures clean looping and allows windowless FFT analysis.
Each sinusoid in the file can have a unique phase and amplitude.
The included wave file generation utility uses GNU MPFR library for extended precision floating point math and FFTW for verification.
Output level is nearest possible to 0 dBTP without going over.
Features
- Audio test tone calibration signals: single tone, multi-tone
- The most accurate sine wave generation utility available
- 177 sample wave files included
- High resolution true peak level measurement utility included
- Output level: 0 dB true peak (new for v 1.2)
- Bit-perfect encoding for all sample formats
- Fractional frequency support
- Extended precision DFT command
- Double precision FFT command
- Future: quad precision FFT
- generator choices: MPFR extended precision or IFFTW double precision
- No file length limit