Availability

Wildwood Express is available for sale at Etsy.

Getting Started

For more information on setting up and configuring Express, see our Quick Start Guide. For more information on using Express, see our Quick Reference Guide.

Videos

For videos that show some of the key features of Wildwood Express, click here.

Note that these videos show Express version 2, which is an earlier version that was released on July 29, 2023 and displayed at Knobcon 2023. The latest version is Express version 3, which was released on December 21, 2023.

Version 3 features a more compact form factor than version 2 and integrates a number of components onto the main board that were present as subassemblies in version 2, including digital audio, touch controllers, I/O expander, USB connectors and Micro SD card slot. It also includes LEDs for the strum pads and improvements to Micro SD card detection.

Function Keys

Express uses function keys to control operations.

Basic Operations

The function keys for basic operations are:

F1	F2	F3	F4	F5	F6	F7	F8	F9	F10	F11	F12
Octave Down	Octave Up	Previous Channel	Next Channel	Previous View	Next View	Previous Menu	Next Menu	Beginning of Song	Play / Stop	Record	End of Song

To Clear the song, press Beginning of Song (F9) and End of Song (F12) at the same time.

To enter Overdub mode, press Record (F11) while Playing (F10) or Play (F10) while Recording (F11).

Yes / No Prompts

The function keys for yes / no prompts are:

F1	F2	F3	F4	F5	F6	F7	F8	F9	F10	F11	F12
Cancel (No)	Confirm (Yes/OK)

Text Input Prompts

The function keys for text input for names and passwords are:

F1	F2	F3	F4	F5	F6	F7	F8	F9	F10	F11	F12
Cancel (No)	Confirm (Yes/OK)	Previous Character	Next Character	Previous Position	Next Position	Insert Character	Delete Character

You can also rotate the rotary encoder to select a character or press the rotary encoder to move on to the next character.

Views

Express provides four distinct views. Each view focuses on an aspect of music production. In basic operation press F5 and F6 to switch between views. F5 selects the previous view and F6 selects the next view.

Note View (Piano Roll)

The Note View is the main view. It shows you the notes in the song. The vertical position of each note represents pitch and the horizontal position of each note represents time. The width of each note represents duration. The color of each note represents its channel.

The background is divided into horizontal and vertical sections with thin gray lines. The horizontal sections represent octaves, with the lowest octave on the bottom. The vertical sections represent measures (equal units of time). The time signature and tempo are displayed at the top, to the right of their starting point(s). A dark red vertical line in the center represents the current position in the song.

The header displays the current octave, the transport control setting, the channel and the instrument assigned to the current position in the channel.

The footer displays the current Menu (i.e. the one you'll get if you press F7 or F8), the location in the song, the duration of the song and the current profile. The profile is marked with an asterisk if it has been modified since it was last read.

You can mark a region of the song by pressing and holding the rotary encoder button. The first press marks the left part of the selection. The second press marks the right part of the selection and the third press clears the selection. You can also press and hold the rotary encoder to switch the scroll action from setting position to inserting/deleting time.

When you open a song and press play, the view scrolls to show you the current position in the song. Menu items allow you to control which channels are displayed.

Song View

The Song View shows the song timeline for all 16 channels, including the current instrument for the channel and the distribution of notes in the channel.

The current time is marked by a dark red vertical line that moves across the view as the song plays. The instrument for the current channel is highlighed in inverse video.

This view is useful for figuring out where you are in a song and which channels are active relative to each other.

Step View

The Step View puts you into Step Mode, and lets you interact with Express like a step based sequencer, where the starting time and duration of each note is quantized to the step's starting time and duration.

Each square represents a step and the total number of steps is controlled by the Steps per Measure menu item. You can create an arbitrary number of pages of steps.

Pressing a note enters that note in the step and advances to the next note. You can have multiple notes per step, all in the same channel, or across multiple channels. Each channel is represented by a color to give you an idea of which channels contribute notes to a step.

Sample View

The Sample View is a new view available with the March 25th 2024 firmware upgrade.

The Sample View puts you in Sample Mode and displays the waveform of the current sample. In Sample Mode, function keys F9 through F12 interact with the sampler instead of the notes in the song. For example, F10 allows you to play a sample and F11 allows you to record a sample (if you have a USB input device connected).

You can also display the waveform for any of the builtin samples by touching a note sensor, or display the waveform stored in a WAVE file by opening a WAVE file using the Sampler menu.

In the Sample View, the Location and Duration in the footer function much like they do in the other views, except that when you're recording a sample, the Duration field shows you the maximum time you can record. After you're done recording, it shows you the duration of the recorded sample.

You can assign a sample to a note by pressing and holding the F9 or F12 buttons and then pressing a note sensor. F9 keeps other samples. F12 clears other samples. To assign just a part of the sample, position to the beginning of the part of the sample you want to assign and press the rotary encoder button to set the left mark. Then position and press again to set the right mark. When you assign the sample, the highlighed section will be snipped out of the total sample. Press the rotary encoder a third time to remove the selection marks.

You can also press and hold the rotary encoder to switch between scroll mode and zoom mode. In zoom mode you can rotate the encoder to zoom in or out on the waveform. Press and hold it again to go back to scroll mode.

Menus

Express groups similar commands together into menus. There are currently 13 menus. In basic operation, press F7 to select the previous menu or F8 to select the next menu.

Most of the properties that are set with the following menus can be saved in profiles. You can update the builtin profiles or create new ones. The most recent profile you've selected is considered the current profile. It's restored when the device powers on.

The following sections describe the menus and menu items. An asterisk identifies new items added for the March 25th 2024 release.

File Menu

The File Menu lets you read and write MIDI files.

• Current Song - Display the name of the current song.
• New Song - Create a new song using the current profile settings.
• Open Song - Read an existing MIDI file from internal flash, USB flash or Micro SD card.
• Save Song - Write the current song as a MIDI file using its current name and location.
• Save In - Write the current song as a MIDI file in a new location.
• Reload Song - Read the most recently saved version of the current song, discarding any unsaved changes.
• Rename Song - Rename the current song (does not automatically save the song).
• Delete Song - Delete the current song from internal flash, USB flash or Micro SD.
• Create Folder * - Prompt to select a parent folder and create a folder in it with a default name.
• Rename File or Folder * - Prompt to select a file or folder then prompt to rename it.
• Delete File or Folder * - Prompt to select a file or folder then prompt to delete it.

Edit Menu

The Edit Menu lets you cut, copy and paste notes to and from the clipboard. You can copy within a song or between songs.

Set the left and right sides of the selection by pressing the the rotary encoder in Note View. The first press sets the left side, the second press sets the right side and a third press clears the selection.

Use the Channel Mute and Solo settings to control which notes are selected for Copy and Erase.

• Scroll Amount - Specify the amount to scroll in Note View when turning the rotary encoder (options include Step, Time, Note and Measure).
• Scroll Action - Specify the action to perform in Note View when turning the rotary encoder (options include Set Position and Insert/Delete time). A shortcut is to press and hold the rotary encoder in Note View.
• Select All - Set the selection to the entire song (from the first note through the last note).
• Cut Selection - Copy the selection to the clipboard and delete it from the song.
• Copy Selection - Copy the selection to the clipboard.
• Delete Selection - Delete the selection from the song, including the time represented by the selection.
• Erase Selection - Erase the selection from the song, preserving the time represented by the selection.
• Paste Clipboard - Paste the clipboard to the current location in the song.
• Quantize Selection - Adjust the starting time and duration of notes to the nearest step. Set the number of steps per measure in the Song menu.

Song Menu

The Song Menu lets you manage the high level properties of the song.

• Set Measure Length - Position to the end of the first measure in Note View and then select this item to divide the rest of the song into equal measures.
• Insert Tempo Change - Insert a MIDI Set Tempo message at the current position.
• Insert Time Signature - Insert a MIDI Time Signature message at the current position.
• Beats per Measure - Set the top number (numerator) in the time signature.
• Beat Unit - Set the bottom number (denominator) in the time signature.
• Set Tempo - Sets the tempo in quarter notes per minute. This value is set automatically if you use the Set Measure Length menu item.
• Change Tempo - Make the song faster or slower by changing the starting time and duration of all notes.
• Steps per Measure - Set the number of steps per measure for the Step View and Quantize.
• Clear Song - Clear the song and start over. A shortcut is to press F9 + F12 together.

Channel Menu

The Channel Menu lets you manage channel properties.

Although channels can be used in many different ways, it sometimes helps to think of a channel as describing the activities of a single member of the band, including selecting an instrument, playing and releasing notes, varying volume and pitch, etc.

By convention, channel 10 is the MIDI drum channel. All other channels can have any instrument assigned to them. Only one instrument can be assigned to a channel at a time.

• Channel - Displays and selects the current channel. A shortcut is to press F3 for the previous channel and F4 for the next channel.
• Bank * - Selects the bank for this channel. A bank is a collection of samples. By default, bank 0 is a builtin collection of 128 General MIDI instrument sounds and bank 128 is a builtin collection of drum or percussion sounds. Conventionally, bank 128 is assigned to Channel 10 to make it the drum channel. You can assign bank 128 to other channels to create more than one drum channel. You can also override the builtin samples with custom samples and/or define new banks. Note: Although MIDI channels are generally numbered starting at channel 1 and MIDI banks are generally numbered starting at bank 0, other devices may number either or both from 0 or 1.
• Instrument - Select the instrument for the current channel. Sets the previous Program Change to the program for the new instrument.
• Display - Selects what to display in Note View and on the LEDs during playback. Options include All Channels or just the Current Channel.
• Channel Status - Lets you selectively mute or solo the channel. Multiple channels can be muted or "soloed". Also controls the notes that are copied to the clipboard.
• Volume * - Sets the volume of the channel relative to the other channels. The default value is 100, meaning full volume, so use this on the channels you want to attenuate (reduce the volume of).
• Reset All - Resets the Mute, Solo and Volume values for all channels to their default value.
• Clear Channel - Removes all the notes from the channel.
• Create Bank * - Creates a new collection of samples. The bank is initially empty, so touching note sensors after creating a bank will not produce any sound. Use the sampler to assign samples to the note sensors for the new bank.
• Delete Bank * - Deletes a bank that was created using Create Bank. The builtin banks 0 and 128 cannot be deleted.

Event Menu

The Event Menu shows the low level MIDI messages that represent the song. This menu is context sensitive and shows slightly different information depending on the message type. The following items are common to all message types.

• Time - Displays the time of the current message in milliseconds. Press and turn the rotary encoder to move forward and backward in the song.
• Mark - Displays or sets whether the current message represents the left or right edge of the selection.
• Find Next - Search for the next message of the selected type.
• Find Previous - Search for the previous message of the selected type.
• Delete - Delete the current message from the song. Use with care!

Settings Menu

The Settings Menu is a collection of miscellaneous properties that don't fit anywhere else.

• Background Volume - Sets the playback volume. If you hear static or clipping when you play a song, try reducing this value and/or Maximum Voices and USB Input / Output Rates.
• Foreground Volume - Sets the volume of the notes that are played on the keyboard or attached MIDI controller.
• Playback Speed - Make the song play faster or slower. This is a temporary change. Contrast with Change Tempo, which actually changes the time and duration of the notes in the song.
• Strum Style - Select the action to perform when you remove your finger from the strum pad. Options include Sustain (continue playing) and Release (stop playing).
• Transpose - Select the number of semitones to transpose the song. There are 12 semitones in an octave (7 white keys plus 5 black keys).
• Animation Time - The number of seconds to elapse before the LEDs start displaying an idle pattern.
• Loop - Select whether playback loops back to the beginning when reaching the end of the song.
• Output Type * - Select the type of audio output to generate. Options include: AUX, USB and AUTO. AUX is audio output to the standard 3.5 mm (1/8 inch) audio connector with powered speakers or headphones. USB is USB audio to the connector labeled USB 2 with a USB audio adapter, headset or speakers. AUTO selects USB audio if a USB audio device is available, otherwise AUX. The default is AUTO
• USB Input Rate * - Selects the USB input rate in samples per second (Hertz or Hz). The options available depend on the capabilities of the device that is connected to USB 2. Input rates above 32000 Hz are automatically downsampled and are represented by two numbers, separated by a slash. The first number indicates the external rate and the second indicates the internal rate. Experiment with the available rates to get the best combination of audio quality and performance.
• USB Output Rate * - Selects the USB output rate in samples per second (Hertz or Hz). The options available depend on the capabilities of the device that is connected to USB 2. Output rates above 32000 Hz are automatically upsampled and are represented by two numbers, separated by a slash. The first number indicates the internal rate and and the second indicates the external rate. Experiment with the available rates to get the best combination of audio quality and performance.
• AUX Output Rate - Selects the AUX output rate.
• Sample Input Level * - Selects the input level for recording samples in decibels (dB). Values less than zero represent attenuation (reduced gain or volume). Values greater than zero represent amplification (increased gain or volume).
• Sample Output Level * - Selects the output level for playing back samples in decibels (dB). Values less than zero represent attenuation (reduced gain or volume). Values greater than zero represent amplification (increased gain or volume).
• Maximum Voices - Configures the number of voices available to the synthesizer. The synthesizer allocates a voice for each note that is playing on each channel. Reducing this value can improve performance. Increasing this value can improve quality, depending on the characteristics of the music you're playing.
• Memory Usage * - Display information on the amount of free memory available for samples, sample groups and other purposes. The display shows Total Free Bytes (TFB), Largest Free Block (LFB) and Total Allocated Bytes (TAB) for two types of internal RAM.

Note: be sure to configure USB for input and output before using USB audio. To do this, connect a USB cable between the USB-C connector to the left of the display and the connector labeled USB 1. This enables the connector labeled USB 2 for USB input and output. See the Getting Started guide for more information.

Profile Menu

The Profile Menu lets you manage profiles. Profiles are collections of settings that are stored in internal flash. They include song properties, like channel instrument assignments, as well as user interface settings. Playlists are also stored in the profile.

When you create a new song. The current profile settings are applied to the new song.

When you open an existing MIDI file, the properties of the song are applied to the profile. This makes it easy to use the properties of an existing song to create a new song in the same style.

• Profile - Displays the current profile and lets you select another profile. Turning the rotary encoder displays profile names. The profile is loaded when you press the rotary encoder.
• Reload Profile - Reloads the profile from internal flash memory.
• Apply to Song - Apply the current profile to the song. At present, this applies only the current instrument set to the song.
• New Profile - Save the current settings as a new profile in flash memory. The profile is automatically given a new name.
• Save Profile - Save the current settings to the profile.
• Rename Profile - Rename the current profile.
• Delete Profile - Delete the current profile. The last profile cannot be deleted.

Pattern Menu

The Pattern Menu lets you control the pattern generator.

The pattern generator creates strums and arpeggios for instrument channels and drum grooves and fills for the drum channel (Channel 10).

• Pattern Generator - Turns on the pattern generator and selects its speed relative to the song's tempo.
• Chord Type - For instrument channels, selects the type of chord (e.g. Major, minor, etc.) Play the chord by pressing the key (C through B) corresponding to the root of the chord.
• Chord Style - For instrument channels, selects the style of the type of chord (e.g. strums, arpeggios).
• Drum Groove - For the drum channel (Channel 10), selects a drum groove.
• Drum Fill - For the drum channel (Channel 10), selects a drum fill.

Reverb Menu

The Reverb Menu lets you control the reverb filter.

The reverb filter is an implementation of Jon Dattorro's reverb algorithm. See https://ccrma.stanford.edu/~dattorro/music.html and https://ccrma.stanford.edu/~dattorro/EffectDesignPart1.pdf for more information.

Parameters are set in the range of 0 to 100, based on the range of permissible values for the underlying property (e.g. 100 ms for maximum pre-delay).

• Reverb - Turns the reverb filter on or off.
• Decay - Set the rate at which reverberations die away.
• Wet/Dry Mix - Set the percent of generated reverb relative to the original input signal.
• Pre-Delay - Set the delay before the first reverberation.
• Pre-Filter - Set the pre-reverb low pass filter amount.
• Damping - Simulate the affect of a hall filled with softer surfaces.
• Decay Diffusion - Control how close together the reverberations sound at the decay phase.
• Input Diffusion 1 - Control how close together the reverberations sound at the first two all pass filters.
• Input Diffusion 2 - Control how close together the reverberations sound at the second two all pass filters.

Playlist Menu

The Playlist Menu lets you create and manage lists of MIDI files to play. Playlists are stored in the profile. You can have one playlist for each profile.

Pressing Play after creating or loading a playlist plays the next song in the list. As each song finishes the next song in the list plays.

You can advance to the next song by pressing F12 (End of Song). Playback will pause at the end of the song if the song is modified. This gives you a chance to save the song.

• Playlist Item - Display the name of the current song in the playlist. Push and release the rotary encoder and rotate to select a new song.
• Add Song - Browse for a MIDI file on internal flash, USB flash or Micro SD card and add to the playlist. Songs are added in alphabetical order, based on their full path name, including folder.
• Add Folder - Browse for a folder of MIDI files on internal flash, USB flash or Micro SD card and add to the playlist, optionally including any MIDI files contained in subfolders.
• Remove from Playlist - Remove the current song from the playlist. The song remains in memory until you open or create a new song.
• Clear Playlist - Remove all songs from the playlist.
• Shuffle Playlist - Shuffle the songs in the playlist.

Network Menu

The Network Menu lets you connect to WIFI to use the web browser interface or to download firmware updates.

The web browser interface shows you the Express display on a larger web browser page and lets you interact using the keys on a standard keyboard.

To navigate to the web browser interface, use the items in this menu to connect to WIFI and start the Web Server. Then open a browser on the same network and point it to http://ip-address where ip-address is the Current Address displayed in this menu (e.g. http://192.168.1.26).

Alternatively, you can configure Express as a standalone WIFI network by pressing the little white button to the top left of the display for two seconds. Express will display its SSID, password and IP Address. Connect to this SSID from another device and open the browser page as described.

• Current Address - Display the connection status, including the IP address if connected.
• Connect to WIFI - Connect to WIFI, optionally using a previous connection or creating a new connection.
• Disconnect from WIFI - Disconnect from WIFI and free any resources allocated to the connection.
• Start Web Server - Start the embedded web server. This is required if you want to use the web browser interface.
• Stop Web Server - Stop the web server and free any resources allocated to it.
• Update Firmware - Check for updated firmware containing new functions and bug fixes. Download and install if available. Requires an internet-accessible WIFI connection.
• Copy OTA to Factory - This is an advanced option. Please do not use unless requested by technical support.

Articulation Menu

The Articulation Menu lets you adjust synthesizer parameters that control amplitude, pitch and timbre to produce an expressive musical note.

The properties in the Articulation Menu are part of the Sample Group. You can save Sample Groups to files and restore them later. You can also define a startup Sample Group that is saved as part of the Profile. This lets you quickly restore a complex set of properties for banks, channels and zones. See the Sampler Menu for more information.

The entire Articulation Menu is new for the March 25th 2024 firmware release.

The Articulation Menu is divided into the following sections:

General Parameters

The General Parameters are a collection of high-level properties that control the mapping of a sample to a note or range of notes.

• Zone * - Select the zone pertaining to the remaining items on the menu. There is one zone for each sample you assign to a channel. The zone defines a collection of properties for a range of notes. Selecting this item and turning the rotary encoder shows you all the zones defined for the channel. Each instrument has it's own set of zones. To find a zone directly touch a note sensor in the Sampler View and it will automatically select the corresponding zone values in this menu.
• Key Center * - Specifies the note that represents the center of the zone. This is initially set to the key you press when you assign a sample to a zone. The synthesizer adjusts the pitch of other notes relative to this value. Set this value to the note associated with the pitch of the sample if you want this and other notes to have the correct pitch. The value shows the MIDI key number (where 60 is middle C) as well as note name and octave.
• Fine Tuning * - Use this if you want the sample to accurately represent the pitch of the note indicated by the Key Center and it is too high or too low. If the sample is slightly sharp, use a negative value. If the sample is slighly flat, use a positive value.
• Low Key * - Sets the first note in the zone. When assigning multiple samples to a bank, Express divides the range between each new sample in half to arrive at this value. If you want to play more than one sample concurrently when a note is pressed, set this value so that it overlaps with a neighboring zone.
• High Key * - Sets the last note in the zone. When assigning multiple samples to a bank, Express divides the range between each new sample in half to arrive at this value. If you want to play more than one sample concurrently when a note is pressed, set this value so that it overlaps with a neighboring zone.

Amplitude Envelope

The Amplitude Envelope settings control changes in the volume of each note as it is played.

• Attack * - Set the amount of time for the volume of the note to go from zero to full volume.
• Decay * - Set the amount of time for the volume of the note to go from full volume to the sustain level.
• Sustain * - Set the volume level that the note reaches during the decay phase. A value of 1 indicates the level does not decrease during the decay phase and the note continues playing as long as the note is pressed.
• Release * - Set the amount of time for the note to go to zero volume after it is released.
• Delay * - Set the amount of time at zero volume before the Attack phase.
• Hold * - Set the amount of time at full volume following the Attack phase.

Modulation Envelope

The Modulation Envelope settings control the pitch and filter cutoff of each note as it is played.

• Attack * - Set the amount of time for the modulation of the note to go from zero to full value.
• Decay * - Set the amount of time for the modulation of the note to go from full value to the sustain level.
• Sustain * - Set the modulation level that the note reaches during the decay phase. A value of 1 indicates the level does not decrease during the decay phase and the modulation continues as long as the note is pressed.
• Release * - Set the amount of time for the note to go to zero value after it is released.
• Delay * - Set the amount of time with no modulation before the Attack phase.
• Hold * - Set the amount of time at full modulation following the Attack phase.
• To Pitch * Set the value to which the modulation envelope influences pitch.
• To Filter Cutoff * - Set the value to which the modulation envelope influences the filter cutoff frequency.

Vibrato LFO

The Vibrato LFO settings control how the vibrato low frequency oscillator is applied to each note to adjust its pitch.

• Delay * - sets the amount of time to delay between pressing a note and starting the vibrato LFO.
• Frequency * - Sets the frequency of the vibrato LFO.
• To Pitch * - Sets the pitch range of the vibrato LFO.

Modulation LFO

The Modulation LFO settings control the effect of the modulation low frequency oscillator on the note as it plays.

• Delay * - Sets the amount of time to delay between pressing a note and starting the modulation LFO.
• Frequency * - Sets the frequency of the modulation LFO.
• To Pitch * - Sets the pitch range of the modulation LFO.
• Filter Cutoff * - Sets the degree to which the modulation LFO influences the filter cutoff frequency.
• Volume * - Sets the degree to which the modulation LFO influences the volume (e.g. tremolo).

Lowpass Filter

The Lowpass Filter settings control the attenuation of higher frequencies.

• Resonance (Q) * - Sets the degree to which the filter gives particular frequencies more gain than others.
• Cutoff Frequency * - Sets the pitch at which the filter attenuates volume.

Loop

The Loop settings control the operation of the sample looper. The loop identifies a regular or repeating part of the sample that is played continuously until the volume decays to zero or the note is released.

• Mode * - Controls looper operation. Values include: No Loop (disables looper); Through Release (loop plays until end of sound); Until Release (loop plays until note is released, then remainder of sample plays)..
• Start * - Sets the starting sample of the loop. To set this value accurately, use the Sample View (and possibly its zoom feature) to position the sample to the start of the loop. Then return to this menu item and press and hold the rotary encoder until a value appears in this field.
• End * - Sets the ending sample of the loop. To set this value accurately, use the Sample View (and possibly its zoom feature) to position the sample to the end of the loop. Then return to this menu item and press and hold the rotary encoder until a value appears in this field.

Miscellaneous and Commands

The remaining parameters are described here.

• Pan * - The relative volume of the left and right channels.
• Attenuation * - The degree to which the volume of the sample should be reduced when playing a note based on the sample.
• Reset to Original Values * - Resets all of the above properties to their original values. Note that the original value for Key Center may not be available.

Sampler Menu

The Sampler Menu lets you control the sampler.

The entire Sampler Menu is new for the March 25th 2024 firmware release.

• Record Sample * - Selects the Sample View and displays the shortcut for recording a sample (F11).
• Play Sample * - Selects the Sample View and displays the shortcut for playing a sample (F10).
• Extract Sample * - Selects the Sample View and displays the shortcut for extracting a sample from an existing note (press the note).
• Assign Sample (Keep Others) * - Assigns the current sample to the most recently pressed note, keeping any other sample assignments for nearby notes in the same instrument. F9 + Note is a shortcut for this in the Sample View.
• Assign Sample (Clear Others) * - Assigns the current sample to the most recently pressed note, clearing all other sample assignments for the instrument. F12 + Note is a shortcut for this in the Sample View.
• Read Wave File (.wav) * - Reads a sample from a standard uncompressed WAVE file. For best results the WAVE file should contain the audio for a single channel, at 16 bits per sample, and a rate of no more than 24000 samples per second. Multiple rates and higher channels are supported for experimental purposes.
• Write Wave File (.wav) * - Writes the current sample to a WAVE file.
• Read Sample Group (.grp) * - Reads a Sample Group from a file and restore the bank definitions, samples, and articulation parameters that it contains. The Sample Group can be created using the Write Sample Group menu item.
• Write Sample Group (.grp) * - Writes a Sample Group to a file so that it can be restored later using the Read Sample Group or Startup Group menu items. The Sample Group contains the bank definitions, samples and articulation parameters. These files can get large, so I recommend using an external Micro SD Card or USB Flash.
• Startup Group * - Configures a Sample Group to restore at power up. Don't forget to save the current profile in order for this item to take effect at the next startup.

Factory Reset

The Factory Reset button is the little white button located to the bottom left of the display. See the Quick Reference Guide for a digram showing its location.

To return your device to its original state, press and hold the factory reset button for ten seconds while plugging the device in. This erases any songs, profiles, samples or sample groups you’ve saved in the internal flash memory. External media is not modified. Internet firmware updates are replaced by the factory image.

Limitations

Express really pushes its hardware to the limits. Here are some implementation details to give you a better idea of what you can do with it.

CPU

The synthesizer is processor intensive. The number of voices and the sample rate are two key parameters that affect performance.

Express allocates a voice for each note that is playing on each channel. If a free voice is not available, it selects the voice that's been playing the longest and reallocates it.

To provide flexibility, Express lets you set the maximum number of voices and the sample rate.

If your music demands lots of voices, you can try reducing the sample rate. If your music demands high quality samples, you can try reducing the number of voices.

When the number of voices and the sample rate are both too high, the synthesizer can't keep the audio pipeline full and you hear noise.

By default, Express operates at either 22050 or 24000 16-bit samples per second (Hz) and 16 voices.

To reduce load, Express downsamples USB audio input and upsamples USB audio output when the respective rates are above 32000 Hz.

To allow experimentation with higher sample rate audio, WAVE files are not currently downsampled.

Note that these sample rates are based on non-lossy content, so it's not really fair to compare them to lossy CD-quality MP3 audio at 44100 Hz.

RAM

After powering on with default setup parameters, Express has about 8 MB of free memory available. Express manages this memory carefully for samples and sample groups so it doesn't run out.

Express allocates about 40% of available memory for the sample buffer when you record a sample. When you stop recording, it resizes the buffer to the amount required and frees the rest. This means you can't use all of available memory for a single sample.

To get an idea of how much time is available for recording, consider the sample rate and the number of bytes per sample. For example 30 seconds of audio at 24000 Hz will consume about 1.44 MB of RAM.

As you work with samples, you will likely find that short samples with loop points work well and can produce sustained audio of virtually any duration. Express makes it easy to snip out the part you want from a larger sample and define loop points.

FLASH

Express provides access to three types of flash memory: builtin local flash, Micro SD Card flash and USB flash.

The builtin flash filesystem is about 2.5 MB and contains profile settings, demo songs and any songs, samples or sample groups you save to it.

The profiles are small and take a total of about 5 KB. The demo songs take about 1.5 MB. That leaves about 1 MB in local flash for your songs and samples.

I recommend storing songs and samples on a Micro SD Card so that you can share them and back them up, but if you want to store them to local flash and you run out of storage, you can delete the demo songs or folders using the File -> Delete File or Folder menu item.