What is the difference between MIDI Program Change (PC) and Control Change (CC)
The abbreviation MIDI stands for "Musical Instrument Digital Interface" (German: "digital interface for musical instruments"). MIDI is an industry standard for exchanging musical control information between electronic instruments. This standard includes both the exact nature of the required hardware and the communication protocol for the data to be transmitted.
For applications in connection with the AMP1, we differentiate between MIDI Program Change (PC) and MIDI Control Change (CC) commands. The AMP1 can process PC commands as well as CC commands from an external MIDI controller. To do this, the controller in question must be connected to the AMP1 via the MIDI1 adapter.
Program Change (PC)
Program Change - or Patch Change - is used to change a patch or preset on a hardware or software component, i.e. to change to a different (sound) memory location. This command is sent in two parts: a selected memory location (or "program") from 0 to 127 or 1 to 128 (depending on the manufacturer) is called up via a selected MIDI channel from 1 to 16.
With the help of the MIDI LEARN function, the AMP1 assigns the channel selection (Clean, Vintage, Classic, Modern), the state of the Boost (on / off), the state of the Reverb (on / off) and (with AMP1 Mercury Edition and AMP1 Iridium Edition) the state of the FX Loop (on / off).
Control Change (CC)
The Control Change command consists of a controller number and a value from 0 to 127. You can use Control Change to control the change in value of certain parameters in real time. The CC command is transmitted in three parts and must be set on the MIDI device: in the first part, the parameter to be edited (e.g. gain, volume, etc.) is determined. The second part consists of the controller number, which determines from which controller (fader, expression pedal, foot switch, potentiometer, etc.) the parameter value to be processed is sent. This is only relevant if the MIDI device used has several controllers that can send CC values. The parameter value in turn represents the third part of the command.
With the help of Control Change commands, depending on the MIDI device, the AMP1 can control the Gain, 2nd Master, Power Soak, FX Loop, Reverb and Boost functions in real time or assign a fixed value to them in a preset.