Fig.23 displays a dialog named "Tuning" accessible from the "Misc" menu. By default, the middle C note ("C4" in English, "do3" in French, "sa4" in Indian notation) is assigned key 60, and the "A4" frequency is 440Hz.

See §1.11 the convention on octave numbering.

There was a confusion in previous versions of BP2 (until 2.6.2). Middle C had been assigned to C5 because of an error inherited from another music software, which went unnoticed until the Csound interface was checked. Therefore old projects may play one octave too high. To compensate this, assign middle C to key 48, and set A4 to 220Hz if you are using Csound. Change values in the "Tuning" dialog and save the project settings.

In a forthcoming version a transposition tool will be available to modify otave numbers in grammar, data and alphabet windows.

The diapason frequency of BP2 is used only for producing Csound scores with instruments that take the "cps (Hz)" format as a pitch parameter.