MPCs

2020-05-23 05:01 pm

Why are MPCs like volume and tempo reset at the start of a new playback, others such as expression, mod and pitch are not?

I couldn't understand why the second and subsequent playbacks were different from the first until I tried experimenting. The simple cure is to restore the controller to its default value as an additional line in the MPC. Pressing f6 twice also solves the problem but is tedious.

Re: MPCs

Reply #1 – 2020-05-24 08:08 pm

Peter,

All modifications in the midi-stream remain even in new files (instrument changes propagate also in other files for instance) unless they are reset (by double F6) or when new midi events override the current values.

The reason why volume is reset is because this is a staff property and restarting will read again the staff property and thus the new volume event is sent.
Here is a default sound staff property as found in nwctxt format for a "new" file :
|StaffProperties|Muted:N|Volume:127|StereoPan:64|Device:0|Channel:1
That suggests that also the pan parameter will be reset.

There is however no tempo parameter (unless you set it explicitly), so there is no real reason why this is reset also. But the default value for tempo is quarter = 120, Therefore, I suppose that this is always set by NWC, even if there is no explicit parameter.

Bart