Version française


With this software, you can find the pitch of a sound, from a microphone or another source. You can tune a music intrument.

Configuration needed : this software runs only under Windows. It was tested under Windows 98 and Windows NT 4; you should not have any problem with more recent versions of Windows.

Principle : the software digitizes the signal at 8 Khz, and processes buffers of 1024 samples. The first processing is a Fast Fourier Transform (FFT) wich result is displayed. The software looks at the spectrum lines to see if frequencies stand out against the others, and in this case, it uses the frequency of the first line. Then, it refines the frequency with a step of 1/100 of semitone, using a normal Fourier Transform.

Display :

  • The upper window displays the input signal; its amplitude must be sufficient.
  • The second window displays the spectrum of the signal, that is the amplitude of the different frequencies making up the signal. If the sound is suffciently pure, some frequency are clearly visible; the software detects them and displays then in red; the first frequency is then refined.
  • At the right of this window, another window gives you the choice of the input filter. You can use the default value.
  • The bottom window displays the note corresponding to the base frequency of the signal, with an accuracy of 1/100 of semitone.
  • At the right of this window, the frequency of the detected note is displayed in bold. Above and below this frequency, the software displays the limits of the refinement interval (see the software principles).

Accuracy : the accuracy of this software is the computer's clock accuracy.

Selection of the input source : use the sound card controls (mixer) : display the recording controls, select the source (for example the microphone) and adjust the recording level.

Language : you can choose between French (default) and English : just click on the corresponding button.

Other parameters : you can choose the input filter (windowing function). The default value gives good results.

Problems :

  • If the software doesn't react to sounds : it's the most frequent problem. You must select the microphone in the sound recording controls (mixer).
  • Strange behaviour : ensure that no other software tries to use the sound card, for example the recorder or a voice recognition software.
  • Crash of the software : never seen. Try to run the software again. If the problem persists, try to reboot the computer. If the software is unable to run on your computer, you can send a message with a description of the problem (specify the Windows version of your computer).

Send a message about Accordeur.exe


Copyright Hervé Jamet - Last update on 18th may 2002