Instruments

Instrument Types

picoTracker supports several different types of instruments, each with its own unique capabilities and parameters. You can switch between instrument types using the Type field at the top of the instrument screen.

Switching Instrument Types

  1. Navigate to the instrument screen by pressing NAV+RIGHT from the phrase screen
  2. By default the NONE instrument type is selected
  3. Press EDIT+LEFT or EDIT+RIGHT to cycle through the available instrument types:
    • SAMPLE: For playing back WAV samples with various effects
    • MIDI: For controlling external MIDI devices
  4. If you've made changes to the current instrument, you'll be asked to confirm before switching types
  5. Note that you cannot change instrument types while playback is active

Importing and Exporting Instruments

Once you've created an instrument, you can save it for use in other projects:

  1. Make sure your instrument has a name set in the "name:" field
  2. Select "Export" on the instrument screen
  3. To import a previously saved instrument, select "Import"

Sampler

screen capture of sampler screen

Sample Slices View

screen capture of slicer screen

The Sample Slices view provides a visual editor for slice start points.

With the waveform display selected, you can use LEFT and RIGHT to select a slice point. The slice field shows the number of the currently selected slice. Press PLAY to audition only the currently selected slice.

Slices are ordered in strict order and they cannot be reordered. Moving a slice backwards will limit it's movement to the position of the previous slice. Moving a slice forward towards another slice will "shove" the next slice(s) to the new position of the current slice.

Slices are stored per instrument and always reference the currently assigned sample. Changing the instrument's sample when slices are present prompts for confirmation, because accepting the change clears all slice start points.

Quick edit: Focusing the cursor on the sample graph allows to quickly edit the slices

Auto slicing: Select the number of slices desired and press the slice button to create evenly distributed slices. Set the number to 1 to quickly delete all slices.

Sample Import Screen

You can enter the sample import file browser by hitting ENTER ENTER (press the ENTER key twice in quick succession) when you are in sample field on the Sample Instrument Screen. This double-press behavior provides a quick way to access the sample import file browser from the sample field in the Sample Instrument Screen.

When in the Project Screen, you can access the sample import file browser with a single press of the ENTER key on the "Import Sample" field.

Samples that you may want to import into a project can be located in any folder but it's recommended to keep them in the folder named /samples at the top-level of the sdcard as that is the default location for the sample import file browser to display when you enter it.

When you're done in the Import Screen, you can press NAV+LEFT to return to the screen you came from (either the Instrument Screen or the Project Screen).

Note: sub-directories will be sorted before files, but otherwise the files will be listed in an unspecified order (ie. not necessarily alphabetical order).

screen capture of sample screen

When entering the import file browser, the current folder is the library root folder /samples. All samples (.wav files) in that folder are listed.

Use the UP and DOWN arrow keys to navigate through the list of available sample files and subdirectories. Subdirectories are indicated with a / prefix. Press EDIT to enter a subdirectory. You can go back to the parent directory by navigating to the /.. entry and pressing ENTER, or by pressing EDIT+LEFT. Hold down PLAY to audition the currently selected sample wave file. To import the currently selected wave file press ALT+PLAY.

Single Cycle Waveforms: Single cycle waveforms are specially marked with a ~ prefix in the file listing. These are WAV files with specific sizes (300 or 1344 bytes) that can be used as oscillators. When imported, they'll automatically be set to oscillator mode in the instrument settings.

A great collection of single cycle waveforms can be found in the Adventure Kid Sample Library.

The status bar at the bottom of the screen shows additional information about the selected file and other information such as:

Basic Controls

Importing Multiple Samples

You can import multiple samples in a single session without leaving the Import View. This powerful workflow allows you to quickly build up your project's sample library:

  1. Navigate to a sample file you want to import
  2. Press ALT+PLAY to import it
  3. Navigate to another sample file
  4. Press ALT+PLAY again to import it
  5. Repeat as needed for all samples you want to import

Each sample will be added to your project's sample pool. The last imported sample will automatically be assigned to the current instrument. Previously imported samples remain available in your project and can be assigned to other instruments later.

When you're finished importing samples, return to the instrument screen by pressing NAV+LEFT.

Auditioning Volume Control

The Import View includes a convenient way to adjust the volume when previewing samples:

The current preview volume is always displayed in the status bar at the bottom of the screen as "vol:XX%" alongside the file size information.

The preview volume uses a non-linear (quadratic) scale that provides more precise control at lower volumes, making it easier to fine-tune quiet previews. This setting is saved with your project and will be restored when you reload it.

Note: While there is no fixed limit for the number of sub-directory levels, there is a maximum of 256 files per directory. Also please note that while FAT formatted sdcards can support upto 256 characters per filename, picoTracker only supports upto 128 character file names and only with ASCII characters.

Supported sample file formats

Sample files must be:

Bit rate and sample rate are converted on import and saved into the project in the native picoTracker format (16bit/44100Hz/Mono or Stereo)

Sample rate converter selection: "Import resampler" option in device screen allows to choose the sample rate converter used: None: No sample rate converter is used and only files <=44100Hz can be used, sample rate conversion happens in realtime during playback and uses a linear interpolator Linear: Linear sample rate conversion is used, fast but not band-limited so it may result in aliasing and high frequency loss. Quality is similar to the previous option but higher than 44100Hz files can be imported Sinc: Fastest band-limited sinc interpolation. Higher quality interpolation but still relatively fast. (97dB SNR, 80% bandwidth) Sinc Best: Best band-limited sinc interpolation supported. Quality is comparable to what can be done on a PC at the expense of much slower conversion speed (121db SNR, 90% bandwidth)

Conversion happens on import into the project before loading into the sample pool. Any subsequent project load will not need conversion.

Conversion speed: Higher bit rate, higher sample rate and better converters all add up to higher conversion times

MIDI

Midi Instrument Screen

screen capture of MIDI instrument screen

A MIDI instrument has the following settings:

Exporting an Instrument

  1. Make sure your instrument has a name set in the "name:" field
    • Each instrument must have a unique name before it can be exported
    • The default instrument type name (e.g., "Sampler", "MIDI", etc.) is not considered a valid name
  2. Navigate to the instrument you want to export
  3. Select "Export" from the instrument menu
  4. Press OK to continue after the export is complete message is shown

Exported instruments are stored in /instruments/ on your SD card.

NOTE: In the future the sample for the instrument will be stored in the same directory as the instrument file but for now is not exported.

Importing an Instrument

  1. Navigate to the instrument you want to import
  2. Select "Import" from the instrument menu
  3. A file browser will appear showing all available .pti files in the /instruments directory
  4. Select a .pti file to import, use the key combo ALT+PLAY to import it
  5. The imported instrument will replace the currently selected instrument
  6. Press OK to continue after the import is complete message is shown

Tips for Instrument Management

Limitations of instrument performance

The picoTrackers CPU limits the number of simultaneous instruments that can be played at once. The specific limit depends on the instrument type and the settings of each instrument. In general the limit is:

Because they are very light weight when it comes to CPU usage, 8 MIDI instruments can be sequenced at once, the limit then coming from the limit of 8 channels (aka tracks) available for sequencing on the picoTracker.

Even given the above limits, it is still possible to mix and match instruments of different types roughly within the above limits. For example 2 samplers and 4 MIDI should in theory be possible. Note this only applies to simultaneously sounding (playing) instruments and if care is taken to limit the number of simultaneously sounding instruments, a larger number of instruments can be defined within a project.

Exporting and Importing Instruments

picoTracker allows you to save and reuse your instrument settings across different projects through the instrument export and import functionality. This feature is particularly useful for building a library of your favorite instruments or using instruments created by other picoTracker users.