Structure Free is a sample player and ROMpler plugin that is part of the Creative Collection available in Avid Pro Tools. It is designed to allow users to load and manipulate audio samples within a Pro Tools environment. The plugin provides functionality for browsing, loading, and key-mapping samples to a MIDI controller, enabling the creation of custom instruments such as drum kits or blended sound patches.
Understanding Structure Free's Core Functionality
Structure Free operates as a sample player, which differs from a full-featured sampler in some capabilities. It primarily uses ROM (Read-Only Memory) sound banks, allowing users to mix and blend different sound banks together. While it incorporates some synthesizer-like controls for modulating sound character and playability, its primary workflow aligns with that of a sampler. Users can load audio files, including Apple Loops, WAV, and AIFF formats, and assign them to specific keys on a MIDI keyboard or virtual keypad.
The plugin can host multiple patches simultaneously. According to the available information, up to four instances of instruments can be active at one time within a single instance of Structure Free. It is also noted as an upgradeable plugin, with the potential to add more patches and enable multiple outputs for individual patches to be recorded onto separate audio tracks in Pro Tools.
Browsing and Loading Patches
There are two primary methods for loading sounds into Structure Free: using the built-in preset menu or browsing the file system directly. The default patch when the plugin is launched is a "Sine Wave."
Method 1: Using the Preset Menu
- Click on the word "patch" located above the main display area. This action brings up the patch menu.
- The menu offers options such as "load," "add," "duplicate," "remove," "cut," and "copy."
- Alternatively, right-clicking on the patch name directly accesses the same context menu.
- To load a new sound, select "load" or "add" and navigate to the desired audio file or preset from the library.
Method 2: Browsing the File System
The browser panel within Structure Free provides a hierarchical view of the computer's file system, allowing for direct navigation to sample locations.
Navigation Controls: The browser includes several controls:
- Left and Right Arrows: Navigate between previously viewed folders.
- Up Arrow: Moves up one level in the directory structure.
- Reload Button: Updates the folder view to reflect any recent changes or deletions made to files on the disk.
- Star Icon: Takes the user to a "Favorites" folder. Users can create new favorites by clicking the plus sign, naming the entry, and adding it to the list for quick access.
- X Icon: Deletes the selected item from the browser view. This action also deletes the corresponding file from the hard drive.
Loading Samples: To load a sample via the browser:
- Navigate to the folder containing the desired audio files (e.g., drum single hits, acoustic guitar samples, soft pads).
- Preview the samples if the function is available.
- Drag the sample file directly into the patch menu area at the bottom of the Structure Free window.
When patches are added, they are assigned a MIDI channel by default (e.g., "A1"). The input level meter will show activity when MIDI data is received.
Key-Mapping Samples for Custom Instruments
A key feature of Structure Free is the ability to key-map individual samples to specific keys on a MIDI controller, enabling the creation of custom instruments like a drum kit from single-hit samples.
Step-by-Step Key-Mapping Process
- Prepare the Workspace: It is recommended to remove any existing patches to avoid conflicts. This can be done by right-clicking on the patch name and selecting "remove" or "remove all patches."
- Load Samples: Using the browser, locate and drag the desired samples (e.g., a kick drum, a snare, a hi-hat) into the patch menu. For a drum kit, load each individual hit as a separate patch.
- Assign MIDI Channel: To ensure all samples trigger simultaneously from a single MIDI track, set all loaded patches to the same MIDI port and channel. For example, set each patch to "Port A, MIDI Channel 1." This can be done by selecting each patch and adjusting the MIDI channel setting.
- Define Key Ranges:
- Navigate to the main menu and select "key range."
- Highlight the first patch (e.g., the kick drum).
- In the key range field, either type the desired note (e.g., "C3") or, if a MIDI controller is connected, play the target key (e.g., C3 on the keyboard). The plugin will assign that note to the patch.
- Repeat this process for each sample. For instance, assign the snare to "D3" and the hi-hat to "E3."
- The Structure Free keyboard display will visually indicate which notes are assigned. Unassigned keys will appear greyed out and will not play the sample.
- Fine-Tune the Sounds: Once mapped, users can adjust each patch's parameters to shape the sound.
- Edit Window 2: This section contains controls for filters and amplifiers.
- Filters: Select a filter type (e.g., low-pass or high-pass). Adjust the cutoff frequency to alter the brightness of the sound (lower cutoff = darker). Resonance and filter envelope (ADSR) settings can also be modified.
- Amplifier: Adjust the attack and release times. Setting the release to a shorter time creates a more staccato sound. The amplifier also controls velocity sensitivity.
- Velocity Sensitivity: The Structure Free keyboard is velocity-sensitive. The velocity of a note—determined by where and how hard a key is struck—affects the volume and timbre of the sound. This can be adjusted in the amplifier section.
- Save as a Preset: To reuse the custom instrument:
- Go to the preset menu and select "save settings as."
- Enter a name for the preset (e.g., "drum kit sample").
- Save it. The preset is then stored in the library and will be available in the menu for future sessions, even if all current patches are removed.
Technical Considerations and Limitations
- File Compatibility: Structure Free supports most common audio file types, including WAV, AIFF, and Apple Loops.
- Instance Limits: A single instance of Structure Free can accommodate up to four instrument patches playing at once. This is similar to the limitations of another plugin, eXpand2, mentioned in the source material.
- Upgrade Path: The plugin is described as "upgrade-able." The available documentation does not specify the details of the upgrade, such as cost, what additional features or patches are unlocked, or where to purchase an upgrade. It only states that upgrades can allow for more patches to play simultaneously and may provide versions that enable multiple outputs per patch for individual recording in Pro Tools.
- Output Configuration: The standard version of Structure Free appears to have a single stereo output. The ability to route individual patches to separate audio tracks for recording is contingent on having a version that supports multiple outputs, which may require an upgrade.
Summary of Workflow for Adding Samples
For users seeking to add samples to Structure Free, the process involves either browsing the file system or using the preset library to locate audio files. Samples can be loaded individually or in batches. The key to creating custom playable instruments is the key-mapping function, which allows specific samples to be triggered by specific MIDI notes. This process is straightforward, involving selecting a patch, accessing the key range menu, and assigning a note. Once mapped, sounds can be further refined using the filter and amplifier controls. Saving the configuration as a preset ensures the custom instrument is preserved for future use. The plugin's flexibility makes it a useful tool for integrating sampled sounds into a Pro Tools production environment.
Conclusion
Structure Free serves as a functional sample player within the Pro Tools ecosystem, offering a bridge between sample playback and basic synthesis. Its primary value for users lies in its ability to browse, load, and key-map audio samples, facilitating the creation of custom instruments like drum kits or hybrid pads. The workflow is centred around drag-and-drop operations and a straightforward key range assignment system. While it has limitations, such as a default of four simultaneous patches and potentially limited output routing in its base form, it provides a solid foundation for incorporating sampled material into music production. Users can save their custom configurations as presets, making it a reusable tool for ongoing projects. The available information confirms its role as a versatile plugin for sample manipulation, though specific upgrade details and comprehensive feature sets are not fully elaborated in the provided documentation.