Sample Alchemy sources in Logic Pro for iPad
Sample Alchemy sound-generating modules are called sources. Four independent sources (labeled A/B/C/D) are available in each preset, and each source has an identical set of controls.
Source components are shown when you tap the A, B, C, and D buttons to select the source you want to edit. Some parameters can be set globally or per source. Global parameters override individual source settings. If you’re new to synthesis or unfamiliar with different synthesis approaches, see Intro to synthesizers.
The components in each source are displayed in three modules: source, synthesis, and filter.

Source buttons: Turn a source on or off. When turned on, a source is a sound-generating module indicated by a handle labeled A/B/C/D that is positioned on the waveform.
Sample Lock button: Tap the lock to keep the current sample when changing presets.
Sample name: Displays the name of the current sample. Tap to open the Browser and load a new sample.
Source handles: Tap the handles labeled A/B/C/D to hear the sample preview. Drag left or right to adjust the playback position, and drag up or down to adjust the first parameter in the source module. You can record the movement of the handles in Motion mode. See Sample Alchemy Motion mode in Logic Pro for iPad.
Mixer button: Show or hide the mixer pane. The mixer lets you adjust the volume for each source.
Mixer sliders: Adjust the volume for each source. A dot indicates which source you’re currently adjusting.
Source module: The first module displays the parameters for the selected source. The first parameter available here changes depending on the selected play mode. For example, in Classic mode you can control the speed at which the sound is played, and in Loop mode you can control the loop speed. The other parameters in this column let you set the panning and tuning for each source.
Source pop-up menu: Choose the source (A/B/C/D) you want to edit, or choose Select All to edit all sources.
Synthesis module: The second module provides multiple sound-generating modes based on different methods of synthesis. Here you can set a synthesis mode for each source. See Sample Alchemy synthesis modes.
Filter module: The third module contains the filter. Here you can set the filter for each source or globally. See Sample Alchemy Filters.
Source module parameters
Playback Speed knob: Set the sample playback speed of the sample. Set low speed values to create gradually evolving textures.
Playback Speed Sync button: Turn on to synchronize the playback speed with the project tempo. Turn off to freely set the playback speed. This button is active only when the loaded sample contains tempo information.
Loop Speed knob: Set the sample loop speed between the start point and end point.
Loop Speed Sync button: Turn on to synchronize the loop speed with the project tempo. Turn off to freely set the loop speed. This button is active only when the loaded sample contains tempo information.
Scrub Jitter knob: Set the depth of the jitter action.
Bow Rate knob: Set the rate of the bow action.
Bow Rate Sync button: Turn on to set the rate in tempo-synced note values instead of Hz. Turn off to freely set the bow rate.
Arp Rate knob: Set the duration of the arpeggiator steps. The arpeggiator is synchronized with the project tempo, and the Rate is set from whole notes (1) to 1/32 notes.
Pan knob: Set the source output position in the stereo field.
Tune Coarse knob: Tune the source in semitone increments.
Tune Fine knob: Tune the source pitch in cent increments.
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