Subsections

- MIDI ports
  - MIDI port configuration
  - Columns in the MIDI configuration ports list:
- Global settings
  - Audio settings
    - Minimum control period
      - Recommendation

# Configuration

## MIDI ports

MIDI ports provide an abstraction layer for your MIDI hardware and synthesizers (which can be both software and hardware synthesizers), and other MIDI applications. Port are numbered. In order to produce sound, each MIDI track is assigned to exactly one MIDI port, to which the MIDI events are then sent.

The advantage of this abstraction layer is that if your system changes, for example you change MIDI hardware, then you need only modify the ports instead of all the tracks using those ports. This is similar to the audio input and output track abstraction to the outside world.

#### MIDI port configuration

In the midi/softsynth configuration menu, you must map the port numbers to the actual devices (by selecting ALSA or jack midi ports, or synth plugins).

Try left-clicking on the "Ports" column of some MIDI track. If you use a soft synth, right-clicking the Ports column of the synth or any track using the synth lets you launch the synth's GUI.

Figure 2.13: Midi configuration window

#### Columns in the MIDI configuration ports list:

GUI:
  For synthesizer devices, indicates if a gui is available and if it is showing. Click to show.
I:
  If present, the port can accept MIDI input. Click to enable or disable it.
O:
  If present, the port can send MIDI output. Click to enable or disable it.
Instrument:
  Selects the instrument to be used when MIDI is played through the port.
Device name:
  Selects or creates a MIDI device assigned to the port. These can be Jack MIDI devices or ALSA MIDI devices (if ALSA is enabled), or soft synthesizers. Jack MIDI devices are created by selecting Create Jack Device from the Device name drop-down menu. Jack MIDI devices can be renamed as you wish by clicking the device name. Soft synthesizers are created by clicking in the soft synthesizer list and then Add Instance. Or you can simply create a new synthesizer track from the arranger track list, or even the mixer menus.
In and Out routes:
  These are for Jack MIDI devices, they are the routes to and from available Jack MIDI ports. Jack may provide different alias names for these ports, you can select which alias is shown.
Default in channels:
  Auto-connect these port channels to new midi or drum tracks.
Default out channel:
  Auto-connect new midi or drum tracks to this channel on the port.
State:
  Indicates the state of the port including any errors opening it.

## Global settings

### Audio settings

#### Minimum control period

Plugins can usually process an arbitrarily small (or large) amount of samples. If some plugin control value changes continously, to provide ideal listening experience, MusE would need to call the plugin 44100 times a second, asking for one single value at a time. With the minimum control period setting, the user can force MusE to ask the plugin for at least N values. Setting this value to 64 would in this situation make MusE call the plugin times a second, asking for 64 values at a time. While doing this will reduce accuracy of control changes, it may also reduce CPU usage, because calling the plugin more often, requesting smaller chunks, is more expensive than calling it seldomly, requesting larger chunks.

##### Recommendation

If you have no performance problems, or if you want to do the final downmix of your project, set this to a low value. If you're experiencing performance problems, increasing this value might help.