βambi

path encoder

a source that moves along a path on the sphere, driven by its own audio

The path encoder encodes a mono or stereo track into ambisonics and moves it along a path you draw on the sphere. Its speed can follow the input: silence stops the source, loud material moves it.

Its window is the one every bambi plugin has; the 3D view, the matrix, regions, presets and the link are explained in the window. This page covers what is the path encoder's own: its three tabs,trajectory, transform and source, and what it shows in the 3D view.

A path encoder window: five tracks as tabs, the 3D view with the paths, the matrix with three cells set, and the trajectory tab.
a path encoder windowdrawn by the plugin
The trajectory tab: lissajous chosen, its az and el amount, az and el ratio, phase, and convert to custom.

trajectory

The path's shape. The row at the top chooses a shape, and under it are that shape's settings:

  • orbit: tilt, axis az and aperture.
  • lissajous: az amount and el amount, how far it swings each way; az ratio and el ratio, how many times; and phase.
  • wave: turns, el amount, wobbles and el offset.
  • polygon: sides, radius and rotation.
  • spiral: turns, from el, to el and start az.

The angles can be automated and modulated, so a path can move with the music. The whole numbers — ratios, turns, wobbles, sides — jump rather than sweep, so they are saved with the instance but not automatable. Choosing another shape resets its whole numbers to their defaults; its angles stay as you last set them.

The trajectory tab on a custom path: closed or open, node 3 of 8, smooth or corner, delete and make start.

a custom path

convert to custom turns the path into nodes you edit on the sphere. The shape you converted from is kept: choose it again and its settings come back as they were. custom is offered once you have converted, and converting again replaces the custom path you have.

  • Drag a node to move it, and its handles to bend the curve. One drag is one undo step.
  • Alt-drag a handle to make a corner.
  • Click the curve to add a node there.
  • Shift-click a node to delete it. A path keeps at least two nodes, and holds up to 24.

The tab holds the same, in words:

  • closed or open: whether the path joins up.
  • For the selected node: smooth or corner, and delete.
  • make start, on a closed path, makes the selected node the first: where the path is cut when it is opened.
The 3D view with a custom path: its nodes as white circles, the chosen one with its handles.
The transform tab: yaw, pitch and roll, each with a rate, and extent.

transform

Where the path sits and how it rotates, whatever its shape:

  • yaw, pitch and roll, each beside a rate in degrees per second that keeps it rotating.
  • extent, from 0 to 2: at 1 the path is as drawn, at 0 it shrinks to its own centre, and at 2 it flips out through the far side.
The source tab: sum, mid/side and stereo; spread, offset and input trim; motion; render.

source

How the track sits on the path and moves along it, in three groups.

  • The input. sum puts one point on the path. mid/side puts the mid on the path and the side either side of it, spread apart. stereo puts left and right on the path, offset apart. input trim, ±24 dB, sets the level before it is analysed for modulation.
  • motion. speed is how fast the source moves, in degrees per second, anddisplace is where on the path it sits. direction is forward or reverse, andmode says what happens at the ends: wrap, ping-pong oronce.
  • render. width, from a point to 180°, is how far the source spreads over the sphere, and width range is the range modulation can move it within.

the 3D view

The 3D view: the selected track's path highlighted with its source on it, the other tracks' paths beside it.

The path is highlighted on the globe and the equirect, with the source on it coloured by its input signal. Every other path encoder in the session is drawn fainter beside it, so you can place each track against the others. Click another track's source or path to switch the window to that instance, as its tab in the header does.

things to try

  1. The kick nudges on every hit. Choose polygon, click displace, click the cell under attack, and drag it up.
  2. The pad opens up when it rings. Click width, click the cell under tonal, and drag.
  3. It drifts slowly, and faster when it is loud. Set speed to a small value, then click speed and give it depth under level.
open beta