You can play in a single register or choose from several options for controlling the register.

Choosing 1. Single register will allow you to use breath or bag pressure to start/stop notes, but will only allow access to one register. The pressure sensor can be used to mimic the way that whistles, flutes, and some bagpipes can be "overblown" to reach the second octave. To use this feature, select 2. Overblow. For fingering patterns that don't use the left thumb, you can instead select 3. Thumb register to allow you use that finger to control the register, which will be familiar to players of many woodwind instruments. To play the upper register, simply uncover the thumb hole. Finally, you can use the "bell" sensor to select the register by choosing 4. Bell register. Uncovering the bell sensor (lifting it off your knee), will access the second register. The functionality for either of these two options can be reversed by turning on the Invert thumb/bell switch. Then covering the left thumb hole or covering the bell sensor will allow playing in the second register, depending on whether option 3 or 4 is selected. In the case of the thumb hole, this will be more familiar to players of instruments with a register key.

Turning on Bagless mode will allow you to configure a button to start/stop the sound instead of using the pressure sensor. This will be similar to many electronic bagpipe chanters that don't use pressure sensing. If you choose you can still select one of the options for controlling the register when using bagless mode. Note: if you choose the bagless option you must also configure a button to Play/stop (bagless mode).

The pressure sensor will normally be calibrated at startup, meaning that the pressure when you plug in the device will be used as a basepoint for determining the pressure level at which sound will be triggered. This is desirable if you are using breath to control the instrument. If you are using a bag with this setting, you will want to squeeze the bag when you plug WARBL in to "tell" it the pressure at which you want notes to begin playing. Alternatively, you can select Learn or enter pressure to use a different pressure. This is usually preferable if you are using a bag instead of breath, and you want to trigger notes at a higher pressure. You can squeeze the bag at the pressure that you would like to use for initial triggering of sound and then click Learn, which will cause WARBL to use the current pressure (as with all settings, you can save this pressure by saving the settings for the current instrument). After clicking Learn, the pressure input cell will flash green and the learned pressure will be displayed. You can also enter the desired pressure manually if you prefer. Simply type in a pressure between 0.0 and 24.0 (inches water) and hit return or enter. The input cell will momentarily turn green to indicate that the pressure setting was sent to WARBL.

Selecting Bag will cause the overblowing settings for bagpipe bags to be used, while selecting Breath will cause the settings for breath (mouthpiece) to be used. These settings are customizable using the Advanced panel if desired (please see the help file within the Advanced panel for information about these settings). If your WARBL firmware version is 2.0 or earlier, you will see a "Vented" switch instead of the bag/breath options.

WARBL mimics open-tone hole instruments by sensing the distance of your fingers from the holes and using this information to bend notes downward. It can detect your fingers a maximum of about 1 cm (~1/2") from the holes. You can reduce this distance using the slider if you don't want to have to remove your fingers as far from the holes to turn off the pitch bend. The downside is that you'll have less precision in bending notes.

You can choose 1. Slide and vibrato, 2. Vibrato only, or 3. No pitch bend, or 4. Legato slide/vibrato. The way slide works is that lowering the finger over the highest uncovered hole will gradually flatten the current note down to the next lower note on the scale, much like on a real instrument. This can also allow you to approximate "half-holing" accidentals. Because of the nature of note transitions in MIDI, sliding between notes can sometimes result in a slight "popping" sound when the new note is triggered. This is quite apparent with some sounds like whistles and less so with other sounds like reed instruments. Whether you choose to use slide may depend partly on the MIDI host and sounds that you're using. The normal slide feature is limited to a maximum of 2 semitones before a different MIDI note is triggered.

The 4. Legato slide/vibrato feature is different from the normal slide in that it allows you to slide seamlessly over a range of more than 2 semitones. The sliding range is determined by the MIDI bend range (semitones) setting in the Advanced Pitch Bend Settings panel. For proper slide and vibrato results, the pitch bend range in the MIDI app or host that you are using must be set to the same number of semitones.

With vibrato, lowering fingers over any open holes (other than the "slide" hole, if you also have slide turned on) will gradually flatten the note down to the selected maximum vibrato depth. The pitch bend contributed by each hole is cumulative, meaning that lowering fingers over multiple holes simultaneously will flatten the note more than lowering just one finger. This gives control over the amount of vibrato, and can be used to simulate sliding even when "slide" isn't turned on. If a finger is covering a hole when a note is triggered and subsequently lifting that finger doesn't cause a different note to be triggered, then that finger will be available to use for vibrato. However, to enable that finger, you first must remove it completely, past where WARBL can first detect it. This is to prevent problems with closed fingering patterns. As an example of how this works, if you trigger a note, completely remove a finger (one that doesn't change the current note), and then place it back down, the resulting pitch will be lower than the originally triggered note because vibrato has been enabled. This is usually intuitive, but it's important to understand because in certain cases it might not be immediately apparent why the resulting pitch is lower than the original pitch.

You can select at the bottom of the panel which holes you'd like to have available for vibrato. If you normally only use a few fingers for vibrato, you may want to select only those holes, to prevent unwanted behavior.

Custom vibrato is a different vibrato option that is only available for some fingering patterns (currently tin whistle, uilleann pipes, GHB, and Northumbrian pipes). For tin whistle and uilleann pipes, the differences from normal vibrato are as follows: 1. Only the first and/or second fingers of the right hand are available for vibrato, depending on the fingering pattern (you cannot select vibrato holes if this option is turned on). 2. Vibrato is not cumulative, meaning that lowering more than one finger doesn't increase the vibrato depth. 3. If a vibrato hole is covered when a note is triggered, the note is immediately flattened (this is the major difference and may be more natural in certain circumstances). 4. When playing a back D with uilleann fingering, uncovering a vibrato hole actually lowers the pitch instead of raising it, which is how real pipes behave. For GHB and Northumbrian pipes, the custom vibrato is designed for closed fingering systems, and sharpens the note when finger R2 or R3 is raised from a closed fingering position (as opposed to the normal vibrato, where lowering a finger from an open position flattens a note).

Note that custom vibrato is not available when any unsupported fingering pattern has been chosen.

Note: For MIDI host apps that allow you to choose the maximum pitch bend depth, you should always set the maximum depth to the same as the MIDI bend range (semitones) setting in the Advanced Pitch Bend Settings panel so that WARBL pitch bend will function as intended.

These settings can be left unchanged by many users, but give more control over how WARBL sends pitch bend messages. The MIDI bend range (semitones) should typically be left to 2, but should correspond to the the pitch bend range setting in whatever MIDI app or host you are using. For some apps this can't be changed, so you can change the WARBL setting to correspond to the app. This will ensure that the expected amount of pitch bend occurs when using vibrato or slide.

You may also want to change the MIDI bend range (semitones) setting if you are using the 4. Legato slide/vibrato option for pitch bend. In that case, the MIDI bend range will also control the number of semitones that you can bend (slide) without triggering a different MIDI note. You must set the MIDI pitch bend range in whatever MIDI app or host you are using to the same value.

Normally WARBL sends a pitchbend message after a new MIDI note is turned on. Some users may instead wish to send pitch bend before the note is turned on by using the Send pitch bend immediately before Note On switch. This may cause pitch bend audio artifacts with some MIDI apps but is the recommended setting for MIDI MPE.

The Send notes as legato switch cause WARBL to wait to turn off each MIDI note until after the next note is sent. This is the recommended setting for most apps and allows many apps to interpret the notes as legato, allowing them to flow seamlessly together.

The three buttons can be programmed to perform different actions. This is useful for sending special commands to MIDI apps or customizing the ability to switch modes.

If a button click is configured to send MIDI Note On/Note Off messages, the normal behavior is to alternate between sending Note On and Note Off messages each time the button is "clicked" (the action actually occurs when the button is released). There is also the option to choose momentary behavior, meaning that the button will send a Note On message when pressed and a Note Off message when released. This is useful if you only want a note to be on when the button is held down, for example for mimicking uilleann pipe regulators. Note: If momentary is selected, other actions using that same button will be disabled, because it's not possible to differentiate other intentions from a momentary press.

If you are sending Note On/Note Off messages, byte 2 is the MIDI note number, and byte 3 is velocity. If you are sending CC messages, byte 2 is the CC number and byte 3 is the value.

Please note that CC messages 102-119 on channel 7 are reserved for the Configuration Tool, so WARBL cannot be programmed to send additional messages in this range.

Selecting Send PC will send a Program Change message to the selected channel. This would be useful, for example, to select a particular instrument in a MIDI host app. Increase PC and Decrease PC are different in that they assume a Program Change value of 1 when WARBl is started, and then increase or decrease it from there. For example, clicking a button assigned to Increase PC after starting WARBL will send a PC message of 2 on the selected channel. These commands are useful for consecutively stepping through the available sounds in a MIDI app.

The momentary switches can also be used when you have selected Octave shift up, Octave shift down, Semitone shift up, or semitone shift down. This allows you to use a button to momentarily shift the octave or key, extending the range of the instrument and allowing any button to act as a "key" for sharpening or flattening a note.

A button can be assigned to begin autocalibration. This can be useful if you anticipate needing to autocalibrate when you don't have access to the Configuration Tool. However, you'll want to use a button combination that can't be triggered accidentally, for example holding button 2 and clicking either button 1 or button 3. Also, when you begin autocalibration with a button combination, you need to be careful not to cover any of the sensors while pressing the buttons, because if you are pressing firmly on the sensors when autocalibration begins it will give WARBL incorrect examples of covered sensors.

The "secret" button commands are a few additional hard-coded actions that involve covering certain tone holes while clicking button 1. These can be useful if normal button actions are used for other functions. They give you an alternative way of changing slide/vibrato mode and instrument. With the “secret” commands turned on, covering only hole L3 while pressing button 1 will change the slide/vibrato mode, and covering only R3 while pressing button 1 will change the instrument. Note that the Use "secret" button commands switch does not have to be on to use the "secret" drone control button, if that option is selected in the Drone Control panel.

The MIDI Console will display up to 300 MIDI messages from WARBL, which can be useful for testing your MIDI setup.

The optical sensors may occasionally need to be calibrated, for example when the device is new, if a new person is playing the device, or the sensors are a bit dirty. Calibration can also be used in a pinch to compensate for having dirty hands, but it's easier to wash your hands...

If the calibration is far off or you want to calibrate quickly, you can run auto-calibration. Begin by holding WARBL in a well-lit room (but not direct sunlight) in such a way that no tone holes are covered (important because it gives WARBL examples of raw sensor readings) and then click Begin auto-calibration. The LED on WARBL will turn on and then you'll have ten seconds to lightly place your fingers over all the tone holes. Pressing harder on each tone hole will make it more difficult to "cover" after auto-calibration. After this the calibration should be reasonably close. Note that the bell sensor will only be calibrated if it is currently plugged in. If this is the case, rest the bell sensor on whatever surface you intend to use with it while also covering the tone holes with your fingers. Note that auto-calibration is always saved immediately; it is not necessary to click Save calibration afterward.

You also have the option of auto-calibrating only the bell sensor. This is useful because the sensor may respond differently depending on the type of clothing you're wearing. To do this, hold WARBL up in the air so the sensor is completely uncovered, click Auto-calibrate bell sensor only, and then lower the sensor onto your knee. After five seconds, the LED with turn off and the sensor will be calibrated.

After auto-calibration or for more frequent adjustments, you can just fine-tune each sensor individually. Clicking the up arrow will make it easier to "cover" the tone hole, while clicking the down arrow will make it more difficult. Note that when you plug in WARBL, values for each sensor will always read zero, and any changes will be relative to the current calibration. Changes to individual sensors will take place immediately so you can test them as you are changing them, but you must click Save calibration for the changes to be saved. Otherwise the calibration will be reset when WARBL is unplugged.

The Configuration Tool connects to WARBL using MIDI protocol to let you control settings.

It is necessary to use a browser that supports Web MIDI, which currently includes Chrome and Opera on Windows, Mac, Linux, Chromebook, or Android. You can also use Firefox or Safari on Mac if you install the WEB MIDI extension. Safari on iOS unfortunately does not yet support Web MIDI, but on iOS devices you can use the free WARBL app. You can also use the free Web MIDI Browser app. For the latter, navigate to this page within the app, and select "Enable SYSEX" in the settings. You may also want to bookmark this page for later use.

The Configuration Tool will try to connect to WARBL if WARBL is already plugged in when the page is loaded, or you can click "Connect to WARBL" if it hasn't connected automatically. Once it has connected, it should show your firmware version in the upper right corner, and it will tell you if there is a firmware update available (see section 8 in the User Manual for updating the firmware). NOTE: If your firmware is not up to date, you will be able to use the Configuration Tool normally, but some options may be disabled (shown in gray).

WARBL has three "instruments" available for use at any time. Each instrument consists of a fingering pattern and a set of associated settings. You can select different fingering patterns for each instrument, or you can select the same fingering pattern for more than one instrument. For example, if you only want to use tin whistle fingering, you can select that option for all three instruments, but still have three different sets of settings available at any time. You may want to have the buttons configured differently for each instrument, for example, or have different register control and/or slide/vibrato settings.

Selecting the tab for each instrument allows you to change the settings for that instrument. You can apply changes to settings to the current instrument, or you can choose to apply them to all three instruments. This can be useful if you want to make three instruments that are the same except for minor differences (which can be changed after applying the initial settings to all three instruments). You can also restore the original factory settings. Please note that WARBL responds immediately to changes to settings, but if you don't save them, those changes will be lost when you unplug WARBL.

The Configure custom fingering... button will show a panel for designing a custom fingering chart that is only activated if you have also chosen Custom in the Fingering pattern dropdown menu.

The Note channel input allows you to select the MIDI channel (1-16) used for sending notes from WARBL. This should typically be left set to "1".

The Transient note filter filters out very brief unwanted notes by adding a small delay to the tonehole sensors. This can be particularly useful when using note annotation software to transcribe your playing. Without the filter, there can be very brief notes that you might not necessarily hear but that will be transcribed. The filter can also be used to "clean up" the sound of your playing by removing "crossing noises" that occur while chaning from one fingering pattern to another. Be aware, however, that because the filter works by adding a delay, setting it too high will give a "sluggish" feel. Set it to "0" for the fastest possible tonehole response, or try a setting of around "8" to filter out the most brief unwanted notes.

You can set the Default instrument that will be active when WARBL is plugged in. This prevents having to click a button to switch instruments if your current favorite instrument is not instrument 1. To set the default instrument, simply click the tab for that instrument and then click Set as Default. This change will be saved immediately.

The Configuration Tool can produce simple square wave sounds if you click the volume icon in the upper-left corner. The sound will not respond to pitch-bend commands or CC messages, but can be useful for testing basic settings.

NOTE: The optical sensor calibration is separate from all other settings, and does not change depending on which instrument is selected. However, restoring factory settings will also restore the initial "factory" calibration.

These settings control the way that the register is changed by overblowing. Each variable below has a setting for a bag and one for the breath (mouthpiece). which settings are used depends on whether you currently have Bag or Breath selected in the main Note Trigger and Register Control panel (the currently selected group of settings are surrounded by a white box). The variables that are most likely to need adjustment are located near the top. Clicking the Bag defaults button will restore the default bag settings for all variables in the panel, and clicking the Breath defaults button will restore the default settings for breath. Units are not shown for some of these settings because they use arbitrary units.

Threshold represents how much pressure is required to move from the first register to the second register. Increasing this setting gives you more control over the registers but also makes it require more breath or bag pressure to overblow.

With wind instruments that respond to overblowing, it typically requires more pressure to move to the second register from higher notes in the scale than it does from lower notes in the scale. The Multiplier setting controls how pronounced this difference is. Again, increasing this setting can give you better control over the register, especially if using a bag, but will also increase the pressure required to reach the second register, from higher notes in the scale in particular.

Note: Setting both Threshold and Multiplier too high can make it impossible to reach the highest notes in the second register because the pressure sensor is saturated, i.e. it has reached the highest pressure it can detect. If you find that you cannot reach the highest notes in the second register, try reducing one or both of these settings slightly.

Hysteresis causes it to be slightly easier to stay in the second register than it is to initially reach that register. In other words, the pressure threshold for moving up to the second register is slightly higher than the threshold for moving back down. This is how real wind instruments behave.

WARBL has the ability to "jump" directly from silence to the second register or to "drop" directly from the second register to silence. Thus, by blowing forcefully (particularly by "tonguing" a note), you can begin playing in the second register without first playing a brief note in the first register. Similarly, by cutting off air pressure suddenly, you can drop directly from the second register to silence. WARBL does this by waiting a small amount of time for a register threshold to be crossed or for the pressure to level off, to detect the player's intent. Increasing the Jump time setting makes it easier to move directly to the second register by increasing the amount of time that WARBL waits to determine the intent of the user. Increasing the Drop time has a similar effect for moving directly from the second register to silence.

Turning on the Force Max Velocity switch will cause WARBL to always send notes with a velocity of 127 (the maximum allowed), which will allow maximum volume from MIDI apps. Some more sophisticated apps interpret high velocity in ways that also affect the timbre of notes, or various other effects. If this is the case, you may want to uncheck this switch, which will cause WARBL to send notes with a velocity of 64 (the middle of the allowed range). The switch has no effect if the "Send Pressure as Velocity" (below) is selected.

Turning on the Send expression as pitch bend switch will cause WARBL to send pitch bend messages based on pressure. This means that for a given note, blowing (or squeezing a bag) gently will cause the note to play slightly flat, while blowing with excess force will cause it to be slightly sharp. This is meant to simulate the way that pressure is used to fine-tune the pitch of real instruments, and can make WARBL sound more lifelike. The Expression depth slider controls the amount of pitch bend. The pitch bend is added to any that is contributed by vibrato and slide, so they can all be used simultaneously. If overblowing is not being used, you have the option of changing the default pressure range used for Expression by clicking the Override... button.

WARBL also has the ability to map pressure sensor values to a MIDI Continuous Controller (CC) note-on velocity, channel pressure, and key pressure, allowing it to function as a MIDI breath controller. These are advanced settings and not needed by many WARBL users. An example would be to send pressure data to CC 7 to control the volume of notes with pressure. The "Send Pressure as Velocity" option overrides the "Force Max Velocity" switch (above).

WARBL makes it possible to control drones in MIDI bagpipe host apps by assigning commands for turning the drones on and off, and then choosing from a few methods for sending those commands. You can choose to send either Note On, Note Off, or CC messages, assigning the channel, byte 2, and byte 3. For Note On and Note Off messages, byte 2 is a MIDI note number and byte 3 is velocity. For CC messages, byte 2 is the CC number and byte 3 is the value.

The commands used for turning drones on and off will depend on the MIDI host app. For example, the Celtic Sounds app uses a Note On command both for turning drones on and turning them off. In some apps such as Universal Piper, you can choose which command you'll use to control the drones.

To assign a specific button action to control the drones, select No drone control but then assign a button action to Turn drones on/off in the Button Behavior panel.

Choosing Use secret button will allow you to turn the drones on and off by pressing button 1 while covering the right-hand index-finger hole.

Choosing Turn on/off with chanter will cause the drones to be on whenever the chanter is playing. This will be true no matter how you control the chanter, so will work in bagless mode as well as using the pressure sensor.

Selecting Pressure will turn the drones on and off at a given pressure threshold, so, for example, you can mimic real bagpipes by having the drones come on at a baseline pressure and the chanter come on at a higher pressure. You can either "learn" the pressure or enter it manually, as with the note trigger pressure.

Use the Preset Import and Export button to exchange your WARBL instrument settings with other users or to archive an instrument setting for later import back into the WARBL Configuration Tool.

These features are only available when the WARBL is connected.

WARBL settings for the currently selected instrument may be exported to a file using the Export Preset button.

The exported file will be named "WARBL_Preset.warbl" and can be found in the "Downloads" directory on your computer. If there is already an existing export file in that directory, Chrome will save the file with incrementing numbers after the "WARBL_Preset" name.

To load an existing WARBL preset file into the current instrument tab, click the Import Preset file selector button.

Select a .warbl settings file from your computer to import. The imported data will be loaded into your WARBL, but not saved permanently to allow you to make additional changes if desired.

To permanently save the settings for the current instrument in your WARBL, click the "Save settings for the current instrument" button at the top of the screen.

Use the pressure graph to view the WARBL pressure sensor readings in inches of H2O over time.

These controls are for creating a custom fingering chart based on a simple pattern of finger positions that are similar to those used for tin whistle, flute, recorder, and many other wind instruments. This can be useful for creating special scales, for example a mixolydian or blues scale, or arpeggios, that are difficult to play on an acoustic instrument or with other existing fingering patterns. You may also be able to emulate real instruments that aren't available in the standard fingering patterns. To use the custom chart, be sure to choose "Custom" for the fingering pattern.

You can enter any MIDI note (from 0-127) for each fingering pattern. Tone holes shown in gray will be ignored, so for most patterns only the highest uncovered tone hole is used to determine the note. There are also a few cross-fingering patterns, which can be used for accidentals. To have WARBL ignore any pattern in the chart, simply repeat the MIDI note from the next highest note in the chart. To have WARBL ignore the left thumb hole, enter a value of "0" for that pattern (the top one in the list).

By turning on the Use both thumb and overblowing for register control switch, it is possible to play three registers by using a combination or overblowing and the left thumb. Then, if you have selected either 2. Overblow or 3. Thumb register in the Note Trigger and Register Control panel, both will be used to give a combined range of three registers. As with other fingering patterns, you can also use the Invert thumb/bell switch to reverse the thumb functionality so that covering the hole raises the register instead of vice versa.

You can choose to use the right fourth finger (pinky) to flatten any note one semitone. If this switch is turned on, the MIDI note assigned to the bottom entry in the chart will be ignored.

It is also possible to fill the chart with presets listed in the dropdown menu. More of these options will continue to be added.

Note: If you are using a custom fingering chart, the default in the Key dropdown menu will be D, but you can still change keys. Any key change will be relative to the default key of D. For example, choosing the key of E will transpose all notes in your custom chart up two semitones.

By turning on the Override pitch expression range switch and using the sliders, you can override the default pressure range used for pitch expression. This is not available if overblowing is being used, because in that case the pressure range has to be calculated in real time based on the current register and overblowing settings.

The input pressure range can be mapped to the output (CC, velocity, channel pressure, or key pressure) range using one of three curves: linear, a power curve (curve 2), or an inverse power curve (curve 3). Adjusting the sliders controls which portion of the overall breath/bag pressure is mapped to which portion of the possible MIDI output range of 0-127.