Pocket Sequencer

Portable and powerful

Unlike most MIDI sequencers, the Pocket Sequencer is small, cheap, battery operated and packs a lot of features. It can be played like a keyboard with built-in scales, sequence up to 128 steps and generate complex arpeggios.

The small display lets you see everything that is happening, and there are no magic button combinations to remember. The polyphonic keys include a full octave of notes to be played. And the replaceable AAA-batteries last a long time.

Use the Pocket Sequencer to play on your portable synthesizers, either while travelling or on your couch at home. Bring it along to test play a synth you are considering. Put it in a drawer in your living room for quick access when you want to jam.

Polyphonic keyboard

Play all MIDI notes polyphonically with the keyboard. Choose between many scales and play single-button chords. It can be played like an ordinary physical piano, or enhanced with powerful features based on music theory.

Polyphonic:
Up to 16 notes

Scales:
Chromatic, Major, Minor, Harmonic Minor, Melodic Minor, Major Pentatonic, Minor Pentatonic, Blues

Modes:
Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian and Locrian

Chords:
Up to 16 notes

Chord inversions:
Up to the 16th inversion, in two different ways

Keynotes (tonic):
All 128 possible notes

Velocity:
1 - 100 %

Polyphonic sequencer

Create multiple sequences with up to 128 steps in total, and see it all on the display. Settings from the keyboard are also applied to the sequence. This means that it can be limited to a scale and that it can sequence chords.

Sequence length:
1 - 128 steps in total across all sequences

Polyphonic:
Up to 8 sub sequences playing at the same time

Beats per minute:
1 - 800

Swing:
51-99% swing or 1-49% inverted swing (short before long)

Gate duration:
1 - 98 % globally

Step probability:
1 - 100 % globally

MIDI output:
Note on/off, clock, start/stop (configurable)

Clock division:
PPQN of 1 - 192 (4 - 800 %)

Transpose:
Transpose sequence keynote live with keyboard

Generative Arpeggiator

Configure the Pocket Sequencer to play complex generative or random melodies. Use a simple signal on a scale to get any of the familiar arpeggios, or route many signals together to form complex polyphonic generative music. How about a sawtooth arpeggio that gets transposed an octave at random? Or a triangle signal whose height alternates between high and low? The Pocket Sequencer's generative mode is like an arpeggiator became modular.

Signal/arpeggio shapes:
Sawtooth Up, Sawtooth Down, Triangle, Square, Pulse, Random Height, Random Width, Fibonacci, Follow

Signal parameters:
Height, Width, Offset, Effect

Signal Effects:
Note output (polyphonic) or MIDI CC

Routing:

Number of signals:
Up to 8

MIDI CC sequencing:
Signals can output to one of 4 configured CC parameters

Small and battery powered

The Pocket Sequencer is really small and comparable to other popular pocket friendly synthesizer gadgets. It can be carried in a pocket with the sensitive components being covered by a protective plate. It is compatable with any synthesizer with a MIDI input, like Korg Volca, Novation Circuit, Korg NTS-1, AudioThingies MicroMonsta and Roland JP-8000 to name a few.

Dimensions:
84 x 60 x 34 millimeters

Weight:
85 grams (with batteries)

Display:
0.91 inch 128x32 OLED (self-illuminated)

Power:
3 x AAA alkaline or micro USB cable (batteries or cable not included)

MIDI plug:
3.5 mm minijack (cable not included)

MIDI TRS:
TRS A and B supported with physical switch

Saving/loading:
All settings, sequences and generative signals are stored together

Designed by Holger Ludvigsen.

How to operate the Pocket Sequencer

Menu

The top part of the screen shows the current part of the menu, with the selected item highlighted.

Octave

This number is the keyboard's current octave.

MIDI output

The currently playing MIDI note is shown here, with the last digit being the note's octave

Pagination left

This arrow means that there are more pages of the menu to the left.

Pagination right

This arrow indicates more menu items to the right.

Instructional videos

Please also see the YouTube channel for instructional videos and demonstrations.

Functionality

Use the main menu to access the different features of the Pocket Sequencer. They are labeled as following:

KEYBOARD

Here you can change the parameters for the keyboard, like velocity, scale and chords. There is also a piano visualization of all the currently playing MIDI notes as well as the current keyboard octave and keynote. Using the keyboard buttons will output notes even if this menu is not open. All the settings here are used globally for sequenced and generated notes as well.

Scales

Choose a scale to lock the keyboard and all notes to that scale. In chromatic scale, the keyboard works like a normal piano, but in the other scales the "white" keys are the 1st, 2nd, 3rd note and so on in that scale. The notes played in the sequencer or generative mode follow the same scale.

The keynote is by default middle C (C4). So if you want to use e.g. A minor, change the keynote to A4 and the scale to minor. It is possible to change the keynote up or down from this to any other note. This will effectively transpose all the melodies up or down.

The scale mode can also be changed. The normal default mode is ionian. Other modes are most commonly used with the major scale, but it is no mathematical reason why they can not be used with any of the other scales.

The scale limit determines how many of the scale's set of notes are actually used. E.g. the Major scale has 7 notes C D E F G A B, but if the limit is set to 5, then only C D E F G will be used. Notes beyond these will then be taken from the next octave. As an example, this can be used to make arpeggios of triad chords by setting the limit to 6. Or to make the Prelude from Final Fantasy by using the first 4 notes of the C major pentatonic scale.

Chords

The chord functionality is very powerful. To use it, select a scale other than chromatic, and set chord size to anything larger than 1. E.g. a chord size of 3 notes is a triad, and 4 notes is a 7th chord. Press any key on the keyboard to play the chord that starts on that note.

Chord inversion can be used to change which note in a chord is the lowest (bass) note. The 1st inversion moves some of the notes a whole octave so that the second note becomes the lowest of them. The 2nd inversion makes the third note lowest, and so on. There are two methods of achieving this: Either all notes before the bass note is moved an octave up. Or the bass note and all notes after it are moved an octave down. These two methods can be chosen by setting the chord inversion parameter to either a positive or negative number.

SEQUENCER

This is where you edit the sequences of notes to be played automatically. All related parameters are also found here, like BPM and gate length. The sequence is visualized with bars, with the lowest note in the sequence being the lowest bar as a visual baseline. If the range of notes is more than the 32 that can fit on screen, they are shown as a vertically scaled line to fit all 128 possible values.

Editing a sequence

To edit the sequence, select EDIT in the SEQUENCE menu. Then press the keys on the keyboard to enter notes step by step. You will see and hear each note when entered. You can also use the arrow buttons to change the currently edited step. To insert a silent step, press the SELECT button on that step. Press SELECT again on a silent step to tie it to the previous step. This will make the previous played note continue, spanning multiple steps.

Sequence parameters

The gate parameter is how long the note is held during each step. E.g. 50 % is half of the total step length. The beats per minute (BPM) is the playback speed, and each beat is 4 steps. The swing parameter adds swing to the rythm. A swing of 50 % means no swing, as every step in a pair takes half of the time. Values over 50 % will make every odd step take longer time, and the even steps shorter. Values below 50 % will invert this and make the odd steps faster and the even steps slower.

The step probability determines the likelihood that the note on each step is actually played. This creates some random variations on the sequence. A probability of 100 % means all are played, and e.g 75 % means that there is a 1/4 chance that a step is simply ignored.

Multiple sequences

You can add new sequences in the MANAGE sub menu. Only one sequence is visible at a time, but all activated sequences are played together polyphonically. The sequences share all parameters, except the number of steps. Using different number of steps makes it possible to do interesting polymeter rythm.

If a sub sequence is opened, its steps are shown in the visualization. Set the sub sequence as not active if you don't want it to output notes when all sequences are played.

Advanced polyphonic sequencing instructions

GENERATIVE

In generative mode, you can set up arpeggios and more complex polyphonic generative melodies.

Signals

The generative system works with "signals" of notes. Each signal is like an arpeggio, and has a form like sawtooth or triangle. They can output notes to be played, or be used as input to the parameters of other signals.

Parameters

Each signal has parameters for shape, height, width, offset and effect. These determine the exact form of the signal output and what the resulting values are used for (effect).

Shape
This is the general shape of the signal. See the different shapes in the figure above. Most of them are simple to understand, but there are some that deserve more explaining:

Fibonacci
This shape is based on something called the Pisano period of Fibonacci numbers. Theory aside, it feels semi-random, but has the property that is repeats itself after a number of steps. The exact number of steps varies with each value of the height parameter.

Follow
This shape will at each step increase or decrease its current value to reach whatever value is in the parameter called width. How much it increases/decreases is given by the height parameter. The result is a kind of softening or dampening of the input signal.

Height
The height is the number of notes between the lowest and highest note. A higher value will make the signal taller and go up to higher notes. This can also be set to a negative number, which for most signal shapes makes it vertically inverted.

Width
The width is the number of steps before the patterns repeats itself. Increasing this value will "stretch" the signal out and add more steps for each cycle. A negative width usually does not make any sense, and can produce undefined behavior.

Offset
The offset is what note is used as a starting point for the signal. An offset of 0 equals the current keynote (which is by default C4, which is "middle C" and note 60 in the MIDI standard), and it can be set to both negative and positive values for notes below or above this.

Effect
The effect is what the signal's resulting values are used for. If the effect is "note", it will output the signal as MIDI notes. Each signal with the note effect will play polyphonically at the same time. If the effect is "silent", it will not output anything. This can be useful when a signal is purely used as input to other signals.

The effect can also be one of 4 chosen MIDI CC parameters. This will output MIDI CC messages that changes the parameter settings on the synthesizer, like filter cutoff or envelope release. The 4 CC parameters you can choose from can be configured in the MIDI CC TARGETS menu found in SYSTEM. A MIDI CC value goes from minimum of 0 to maximum of 255. (With the CC effect, an offset of 0 does not output the value of the keynote like with the other signals, but it is actually the value 0.)

Routing signals

A signal can be used as input to another signal's parameters. To do this, change the parameter value down beyond zero. After zero, the other signal names show up as possible values. And after the 8 possible signals, the negative values show up if you want that instead. Combining signals in ingenious ways makes an infinite number of interesting generative sequences possible.

Signal 1:

Signal 2:

Signal 3:

Signal 4:

Signal 1 with offset = signal 2:

Signal 1 with width = signal 2:

Signal 3 with offset = signal 4:

How routing works

All parameters except shape can be set to refer to other signals. The other signal will be evaluated each step and used directly as the parameter's value. For a parameter like offset, this will simply move the signal up or down differently for each step. For a parameter like height, it is a bit more complicated as it depends on how far we got in the signal before the values changes. E.g. a sawtooth wave with a low height will be a gentle slope, and then in the middle of that slope, if the height parameter becomes a larger value, the slope becomes steep.

The effect parameter is treated specially, and if it is routed from another signal's values, those values are mapped to one of two possible values: silent or note. If the other signal's value is an even number, it interpreted as silent. If it odd, it is a note.

Generative tutorial

SYSTEM

This is where you can change global settings like MIDI channel, MIDI clock, PPQN and more. The current version number of the software is also displayed. There is a MIDI CC menu here when 4 CC parameters can be sent to the connected device. These CC parameters are also used for CC sequencing in the generative mode, but only the CC numbers, not their current value. There is also a button to send random values to all the 128 possible CC parameters. It often results in gibberish patches, but can be interesting!

SAVE & LOAD

Here you can save and load the entire state of the Pocket Sequencer. All parameters, sequences and generative signals are stored together. The system will, by design, not load the save automatically during startup.

Updates for Pocket Sequencer

The firmware of the Pocket Sequencer can be updated to access new functionality and fix known bugs. Each update contains the updates before it, so you need only install the latest one.

Instructions

The updates are made for working with a Windows PC, but there is a provided script for Mac OS if you are of that kind (credits to Matthew Callis!). You will need a micro USB cable (not included) to connect the Pocket Sequencer to the computer. The updates will possibly delete all saved data on the Pocket Sequencer.

1. 1. Download the update zipfile
2. 2. Unzip the file contents
3. 3. Connect the Pocket Sequencer to the PC with a micro USB cable
4. 4. Run the file UPDATE.cmd by double clicking on it
5. 5. Wait for the update to complete
6. 6. Clear the stored data by doing a fresh SAVE in the SAVE & LOAD menu

If any problems occur, please try a different micro USB cable. Some cables only support power, and can not transfer data.

Update 1.3

File

Pocket-Sequencer-1.3.zip

New functionality

• Scale modes can now be chosen: Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian and Locrian
• MIDI CC sequencing is now possible by using up to 4 possible CC-parameters as generative signal target
• More parameters are now stored during saving and loading: keynote, PPQN and what happens when keyboard is pressed during play
• Added button that transmits randomized values for all 128 MIDI CC values
• Changed the behavior for the play button: If used outside the sequencer or generative menu, it now plays or stops either the sequence or the generative signals depending on which of those were played last
• Signal type is now called shape, which is more descriptive
• Added a new signal shape based on Fibonacci number using the Pisano period
• Added the current keynote position to the keyboard visualization
• Changed how steps are visualized when the range between minimum and maximum is larger than can be shown: The steps are now shown as a thin line that is scaled vertically by 1/8th
• Added swing; both normal swing at 51-99 % and inverted short-long at 1-49 %
• Made it possible to set a limit to the number of notes actually used in a scale
• Renamed signal transpose to offset, since transpose in music usually means changing the keynote, but the offset is actually in scale
• Renamed signal target to effect to avoid the misconception that target=signal X is actually influencing the signal X, while it is actually the other way around
• Renamed the effect void to silent since people not familiar with computer programming do not use the term void
• Replaced the signal shape "walk" with "follow", which approaches a target value. This can fill the same role, but is less prone to straying towards the infinite
• Made it possible to have negative values in the signal parameters height and width. Negative height usually inverts the shape, and negative width is not defined except for the "follow" shape
• Changing behavior for the target/effect parameter when another signal is used as input. Instead of using ranges 0-5 and 6-11, now even values mean silent, and odd values mean note output. This is simpler to explain to the user.

Bug fixes

• Saved sequences with length other than 8 steps previously did not get the number of steps correctly set after a load
• The chord inversion feature was not actually implemented correctly. Previously the top X notes were moved up/down. But now the necessary notes are moved to make the x-th note the lowest.
• Although 8 sub sequences was supposed to be possible, the required memory was not allocated correctly, making a maximum of 6 sub sequences possible. This is now corrected.
• For the random generative shapes "random height" and "random width", they previously shared the same pseudo random number generator, making the behavior unpredictable when several random signal were used simultaneously. This is now corrected
• For the generative shapes sawtooth and triangle, they previously did not work correctly when height was lower than width (gentle slope)
• In some situations, like when editing a playing sequence, the number of steps was not shown correctly, and could not be edited

Update 1.2

File

Pocket-Sequencer-1.2.zip

New functionality

• You can now use another generative signal as input to the target parameter, making silent steps possible in generative mode
• Added option for what keyboard presses do during live play: Transpose the keynote or play the note polyphonically
• Made a configurable parameter for clock division (PPQN), which reduces or increases the rate of the MIDI clock compared to the sequencing
• Added simple functionality for sending a single MIDI CC message from system menu
• The update script now attempts to find the correct usb port name of the connected Pocket Sequencer

Bug fixes

• When starting and stopping a sequence during generative play, the currently playing generative note is not interrupted. And vice versa.

Update 1.1

File

Pocket-Sequencer-1.1.zip

New Functionality

• Multiple sequences can be played polyphonically at the same time
• Sequence and generative melody can be played at the same time
• Generative parameters can be changed while playing without interrupting live play
• Added tie note as a possible sequence step
• Added button for replacing all currently active sequences with the selected one
• Edited sequence step can be selected independently from playing step during live play
• Sequences that are active or open are marked with symbols
• Now opening and activating every newly created sequence by default
• Now showing firmware version number in the SYSTEM menu
• Added button for killing all hanging MIDI notes
• Changed default number of steps to 8

Bug fixes

• Silent steps are now applied to the open sequence when editing, instead of always on sequence nr 1
• Fixed bug when trying to add more than the maximum number of sequences
• Making it impossible to delete the last remaining sequence
• Fixed bug when trying to have 128 steps in a sequence
• No longer possible to attempt to select less than 1 or more than 128 steps in a sequence
• Clear steps now works not only on the first sequence