Contents

Channels, Ports & Controls

A MIDI file is really a whole band playing at once, organised into channels and shaped by a handful of live controls. None of this is essential to press play, but knowing the words makes the Mixer, the visualiser, and Performance Mode much easier to follow.

Channels#

A MIDI stream is divided into 16 channels, and each one usually carries a single instrument: piano on one, bass on another, strings on a third, and so on. The visualiser shows all 16 at once, one row each.

One channel is special. Channel 10 is reserved for drums and percussion, where each note triggers a different drum sound (kick, snare, hi-hat) rather than a pitch.

Ports (A, B, C, D)#

Sixteen channels is plenty for most music, but some files want more. A port is a single MIDI connection carrying its own set of 16 channels. PXR handles up to four ports, labelled A, B, C, and D, for up to 64 channels in total.

Use the port button on the transport to choose which port's 16 channels the visualiser shows, and route different ports to different devices with custom port presets. There is more on this in the Visualiser.

Mute and Solo#

Two quick ways to change what you hear, without touching the file itself:

Mute silences a channel.
Solo does the opposite: it plays only the soloed channel (or channels) and quietens everything else.

They are perfect for picking out a single part to learn it, or for dropping the drums to hear the melody. Set them in the Mixer, or by clicking a channel in the visualiser. They affect playback only, so the file is never changed.

The Mixer window, a wide mixing desk with one vertical strip per MIDI channel. Each strip stacks rotary knobs for pan and effect sends, mute and solo buttons, an instrument readout, and a tall level fader topped with a green signal meter, with a master strip on the right.

The performance controls#

These shape how notes sound as they play, the same expressive controls a keyboard player reaches for:

Velocity: how hard a note is struck, which sets its loudness and often its tone. A gentle press and a firm one really do sound different.
Modulation: usually a gentle wobble (vibrato) brought in with the modulation wheel, giving a held note some movement and life.
Pitch bend: smoothly bending a note's pitch up or down, like easing a guitar string.
Sustain: holds notes ringing on after the key is released, exactly like a piano's sustain pedal.

In a file, these are part of the performance the composer recorded. You can also apply them yourself in Performance Mode.