Introduction

The EP-133 K.O. II is a standalone sampler and composer from Teenage Engineering — a battery-powered instrument for making beats from scratch, anywhere. It carries forward the spirit of the PO-33 K.O!, the pocket-sized sampler that punched well above its weight, and scales it up into a full-featured production tool.

At its core, K.O. II is a sample-based drum machine and sequencer. You load sounds onto 12 velocity-sensitive pads, arrange them into patterns with a step sequencer or by playing live, and build those patterns into complete songs. It records from a built-in microphone, a stereo line input, or by resampling its own output — so you can layer, chop, and reshape sounds without ever touching a computer.

The first edition of the K.O. II came with 64 MB of memory. As of late January 2026, new models have 128 MB.

What’s inside

• 64/128 MB of sample memory across 999 sample slots
• 4 groups of 12 pads each, with 99 patterns per group and up to 99 bars per pattern
• A high-resolution sequencer running at 96 PPQN with note intervals from whole notes down to 32nd notes, swing, and free-time recording
• 6 built-in effects — delay, reverb, distortion, chorus, filter, and compressor — plus 12 pressure-sensitive Punch-In FX for live performance
• Song mode for chaining scenes into complete arrangements
• Sidechain compression, time stretching, and auto/live chop for sample manipulation
• MIDI in/out (TRS and USB), sync in/out (compatible with Pocket Operators, Eurorack, and vintage drum machines), and USB-C for power, sample transfer, and firmware updates

Who it’s for

K.O. II sits at the intersection of immediacy and depth. If you want to sketch a beat in five minutes using the built-in mic and factory sounds, you can. If you want to build a multi-scene arrangement with resampled loops, sidechained bass, and MIDI-sequenced external synths, you can do that too. It runs on 4 AAA batteries and fits in a bag.

This manual covers firmware version 2.0.5 and walks through every feature of the device, from first power-on to advanced production techniques.

Quick Start

What’s in the box

• EP-133 K.O. II unit
• Quick start guide
• 4× knobs (attach to the posts on the front panel)
• 10″ box with paper foam tray

Power up

1. Lift the top lid to reveal the battery compartment.
2. Insert 4× fresh AAA batteries, following polarity markings.
3. Slide the orange power switch (top right) to power on.
4. The LED screen lights up immediately — you’re in.

Make a beat from scratch

1. Load a project. Hold MAIN + a pad (1–9) to select a project. Projects 1–5 come pre-loaded with sounds; 6–9 are empty.

2. Browse sounds. Press SOUND, select a group (GROUP A–D), then a pad. Use − / + to scroll through sample numbers.

3. Go to Main. Press MAIN — the screen shows the current step position.

4. Record. Tap RECORD, then PLAY for a four-beat count-in. Hit the pads to punch in your beat. Press PLAY to stop, or RECORD to keep the beat going but stop recording.

5. Extend pattern length. Hold RECORD + + to add bars (default is 1 bar).

6. Add a bassline. Switch to GROUP B, select a bass sound, press KEYS to play it across the pads like a keyboard. Record it in.

7. Add a melody. Switch to GROUP C, same technique.

8. Sample something. Switch to GROUP D, press SAMPLE — pads flash to indicate they’re ready. Hold a pad and make some noise into the mic or line-in. Release to stop.

9. Add FX. Press FX, use FADER for send level, − / + to choose an effect.

10. Punch-in FX. While playing, hold FX and press pads to trigger live performance effects.

11. Commit. Press SHIFT + MAIN to save the current arrangement as a scene and start a new one. Commit often!

Step sequence a beat

1. Press MAIN, then hold SHIFT + − until the display reads 1.1.1 (first step).
2. Hold RECORD + a pad to place that sound on the current step.
3. Use − / + to navigate between steps.
4. Try kicks on 1.1.1, 1.2.1, 1.3.1, 1.4.1 (four on the floor) and snares on 1.2.1, 1.4.1 (backbeat).
5. Press TIMING and turn KNOB X to change the note interval (1/8, 1/16, 1/32, etc.).
6. Press TIMING and turn KNOB Y to adjust swing.

Hardware Overview

EP-133 K.O. II is a sampler and composer with 999 sample slots, 12 sample pads, 4 group pads, a high-resolution sequencer, 6 built-in effects, and 12 punch-in effects.

Inputs & outputs

Top panel

Sync modes

Front panel

The front panel features:

• 12 sample pads (also function as a number pad 0–9, dot, enter)
• 4 group pads (GROUP A–D), also used for new pattern, undo, copy, paste
• KNOB X and KNOB Y — context-sensitive rotary encoders
• FADER — assignable to volume, pan, FX send, pitch, attack, and more
• SOUND, MAIN, TEMPO — the three main mode buttons
• FX, SAMPLE, KEYS, TIMING — function buttons
• RECORD, PLAY, ERASE — transport and editing
• SHIFT — modifier that opens secondary functions on nearly every button
• − and + — navigation, browsing, and parameter adjustment

How K.O. II Works

If you’ve used an MPC, a Maschine, or even a DAW with a sampler plugin, the core concepts here will be familiar — but K.O. II organizes them in its own way. This section is the mental model. Once you have it, the rest of the manual is details.

Main and Sound: the two primary modes

K.O. II’s interface is built around buttons that change what the pads, knobs, and fader do. Two of them matter most:

MAIN

Home base. Press it and you’re looking at the sequencer — the current step position, your pattern, your arrangement. This is where you play pads to trigger sounds, record patterns (live or step-by-step), manage scenes, and build your song. When you’re lost, press MAIN.

SOUND

Your sample manager. Press it and you’re looking at which sample is loaded on the selected pad. Browse the 999-slot sample library with − / +, adjust volume with KNOB X, pitch with KNOB Y. You come here to set up your sounds, then go back to MAIN to use them.

SHIFT + SOUND opens Sound Edit — a deeper editing layer that contains six pages you navigate with − / +: play mode (oneshot / polyphonic / legato), trim, envelope, time stretch, per-pad MIDI channel, and mute groups. Edits here are per-project and don’t alter the underlying sample file.

There’s also the TEMPO mode, where you set the BPM, metronome volume, and time signature for the current pattern. This is less of a “mode” and more of a settings screen.

Function buttons: SAMPLE, FX, KEYS, TIMING

These buttons activate specific functions on top of your current context. They change what the pads and knobs do without switching you out of your workflow:

SAMPLE

Enters a dedicated sampling mode — pads blink, hold one down to record from the mic, line-in, or internal resample bus. SHIFT + SAMPLE opens Chop mode for slicing samples across pads.

FX

Lets you choose and configure one of six effects (delay, reverb, distortion, chorus, filter, compressor) for the current group. While playing, hold FX and the pads become 12 pressure-sensitive punch-in effects — one of K.O. II’s signature features. SHIFT + FX opens the master compressor and sidechain.

KEYS

Turns the 12 pads into a chromatic keyboard for the selected sample. Essential for playing bass lines and melodies.

TIMING

Sets the note interval (1/1 through 1/32, including triplets), swing, and quantize vs. free-time recording. Hold TIMING + a pad for note repeat. SHIFT + TIMING opens timing correct for quantizing individual notes.

Four groups, one song

Every project gives you four groups — A, B, C, D — each with its own 12 pads, its own patterns, and its own FX send. Think of them as four separate tracks. A common setup: drums on A, bass on B, melody on C, loops or resampled material on D.

All four groups play simultaneously. A scene is a snapshot of which pattern each group is playing. You build a song by creating scenes (verse, chorus, bridge) and chaining them in Song Mode.

The commit workflow (SHIFT + MAIN) is central to how K.O. II wants you to work: commit to save the current scene, which duplicates it so you can freely change patterns for the next section without losing what you had. It’s version control for your arrangement.

Recording: live vs. step

There are two ways to get notes into a pattern:

• Live recording: Tap RECORD then PLAY for a count-in, or hit them simultaneously to start immediately. Play the pads in real time. Press RECORD again to stop recording but keep playing, or PLAY to stop everything.

• Step sequencing: With playback stopped, use − / + to navigate to a step, then hold RECORD + a pad to place it there. You can set velocity (SHIFT + KNOB X) and duration (SHIFT + KNOB Y) per step.

Both approaches work with quantized or free-time recording.

Sampling and resampling

Press SAMPLE and hold a pad to record. Release to stop. Cycle sources with − / +: mic, line-in (mono/stereo/L/R), or resample.

For longer or hands-free recordings, press SHIFT + pad to latch, then PLAY — K.O. II records the length of the current pattern automatically.

To resample, set the source to RSP, latch a pad on an empty group, and play to bounce your beat down to a single sample.

The fader

The FADER is assignable. By default it controls group volume, but hold FADER and press a pad to reassign it to pan, FX send, pitch, attack, release, or other parameters. Fader movements can be recorded as automation — hold RECORD and move it.

Everything is SHIFT + something

Nearly every button has a SHIFT combo that unlocks a secondary function:

If you’re looking for a feature, try holding SHIFT first.

Screen & Navigation

K.O. II has a custom segmented display with 66 unique icons representing different features and states. The display shows step positions, parameter values, sample numbers, and mode indicators.

Icon map

The display uses icons to indicate active modes and states. Common indicators include:

• Sound mode, Main mode, Tempo mode icons
• Record arm, play, metronome
• FX active, Keys mode
• MIDI activity (MIDI icon or USB icon)
• Undo available (umbrella icon)
• Quantize / free time
• Battery status

Navigation basics

Controls Reference

Groups

Buttons GROUP A through GROUP D select between 4 groups, each containing 99 patterns and 12 sounds. In Main mode, the group pads double as undo, copy, and paste — see Shortcuts & Key Combinations for the full list.

Pads

The 12 pads trigger sounds and double as a number pad for entering values.

Minus and plus (− / +)

− and + are central navigation controls. Depending on context, they switch between scenes and patterns, adjust pattern length, navigate steps, browse effects, nudge notes, adjust tempo, and select sounds.

Shift

SHIFT is the gateway to secondary functions. Almost every button on K.O. II has a SHIFT combo — see Shortcuts & Key Combinations for the full list.

Fader

By default, the FADER controls group volume (level). To change its assignment, hold FADER and select from the options printed above the pads: level, pan, FX send, pitch, attack, release, filter cutoff, and filter resonance.

Knob X and knob Y

KNOB X and KNOB Y are context-sensitive encoders. Their function changes depending on the active mode — from FX parameters to tempo, swing, compressor settings, and more.

Timing

Press TIMING to access note interval, swing, quantize, and note repeat. See Timing & Quantization for full details.

Sample

Press SAMPLE to record from the built-in mic, line input, or internal resample bus. See Sampling for full details.

Workflow

Projects, groups, patterns, scenes

K.O. II organizes your work around a few interlocking concepts:

A project is your top-level workspace — think of it as a song file. K.O. II holds 9 projects.

Within a project, you have four groups (A–D), each with its own set of 12 samples and its own patterns. Groups play simultaneously, like four parallel tracks.

Each group can hold up to 99 patterns (up to 99 bars each). A pattern is a sequence of notes for that group’s sounds.

A scene ties it all together: it’s a combination of one pattern per group. Think of scenes as sections of your song — verse, chorus, bridge. Each project holds up to 99 scenes.

Song positions let you chain scenes into a complete arrangement that plays start to finish.

Commit

Press SHIFT + MAIN to commit. This duplicates the current scene so you can save your ideas before moving on. Commit often — it’s your safety net for building song structure.

Song mode

Song mode plays through song positions 1–99, each assigned to a scene. The length of each song position matches the longest pattern in that scene.

Song list editor

1. Hold MAIN, then press the ENTER pad to open the song list editor.
2. The screen shows the current song position.
3. + / − navigate between song positions.
4. SHIFT + GROUP A — add a new scene to the song list.
5. SHIFT + − / + — change which scene plays at the current position.
6. SHIFT + GROUP C — cut the current scene to clipboard.
7. SHIFT + GROUP D — insert a scene at the current position.

Playback

Sound Mode

Press SOUND to enter Sound Mode. This is where you assign samples to pads and adjust basic parameters.

K.O. II stores up to 999 samples (or 64/128 MB, whichever comes first).

Browsing sounds

Default sample organization

K.O. II ships with over 300 factory samples. Record your own or transfer via the EP Sample Tool.

Basic sound parameters

In Sound mode:

• KNOB X — Amplitude / volume (AMP)
• KNOB Y — Pitch (PTC)

Sound Edit

Select the sound you want to edit, then press SHIFT + SOUND to enter Sound Edit. Use − / + to navigate through 6 edit pages.

Play mode (Sound)

Adjust how a sample plays back and where it sits in the stereo field.

• KNOB X — Play mode:
  • Oneshot — Monophonic, plays the whole sample once
  • Key — Polyphonic, allows multiple simultaneous plays (perfect for keyboards)
  • Legato — Monophonic, continues from the same playback point when retriggered
• KNOB Y — Pan (left / center / right)

Trim

Fine-tune the start and end points of your sample.

• KNOB X — Start point
• KNOB Y — Length / end point

Envelope

Shape the attack and release of your sample playback.

• KNOB X — Attack (fade in from silent to full volume)
• KNOB Y — Release (how long the sound continues after releasing the pad)

Time stretch

Match sample tempo to your project BPM.

• KNOB X — Time stretch mode:
  • BPM — Stretch to match project tempo (set sample’s original BPM with KNOB Y)
  • BAR — Automatically fit sample to a time division (1 bar, 2 bars, etc., set with KNOB Y)

MIDI

Configure per-pad MIDI settings for external control.

• KNOB X — MIDI channel (allows each pad to send/receive on a different channel)
• KNOB Y — MIDI root note (align the device’s root note with your sample)

Mute group

Group samples together so that only the most recently triggered one plays — the others are cut off. Classic use: open and closed hi-hats.

When no pad is selected, all pads flash. Press a pad to add it to the mute group. Pads in the mute group light up.

Recording

Live record

Pattern length

• Default: 1 bar.
• Hold RECORD + + to extend; RECORD + − to shorten.
• RECORD (arm) + SHIFT + + duplicates the pattern length (with existing notes).
• You can change length on the fly while playing.
• Maximum: 99 bars per group.

Step sequence

While K.O. II is stopped, use − / + to step through your pattern.

Keys mode

Press KEYS to play a selected sample chromatically across the 12 pads.

Sampling

Enter sample mode

Press SAMPLE — all pads blink to show they’re ready. Press and hold any pad to start recording via the mic or line-in. Release to stop. Press the pad again to audition your recording.

Input sources

Press − / + while in Sample mode to cycle through sources:

Input controls

• KNOB X — Input level
• KNOB Y — Threshold (recording starts when input exceeds this level)

Hands-free sampling

Run out of hands? Press SHIFT + a pad to have K.O. II hold the pad for you. Combine with resample to capture chords and layered sounds.

Resample a pattern

1. Enter Sample mode, engage hands-free (SHIFT + pad).
2. Press PLAY — K.O. II samples the length of the current pattern.
3. Use − / + to set a specific number of bars before pressing PLAY.
4. Press SAMPLE to stop.

Chop

Chopping takes a single sample — a drum break, a chord progression, a vocal phrase — and splits it into pieces spread across the pads. You can then rearrange the pieces by playing or sequencing them in any order, which is one of the fundamental techniques in sample-based production.

Press SHIFT + SAMPLE to enter Chop mode.

Auto-chop

Press a group pad (GROUP A–D) to auto-chop. K.O. II uses beat tracking to intelligently divide the sample into slices, populating pads from bottom-left to top-right. Use − / + to adjust the number of slices.

Live chop

Press pads as the sample plays to manually place chop points. The break is assigned based on timing between pad presses.

After chopping, refine start/end points with KNOB X (start) and KNOB Y (end). Hold SHIFT for finer control.

Transferring samples via USB

Transfer samples to/from a computer via USB-C at teenage.engineering/apps/ep-sample-tool.

Sound library

Every sample you record is stored in the sound library and automatically assigned the next available slot. To choose a specific destination, hold SOUND, type a number on the pads (e.g., 303), press ENTER, then hit SAMPLE.

Effects

Press FX to enter the effects menu. Each group can send to one master FX, and the entire mix passes through a master compressor.

FADER controls the FX send level for the current group. Use − / + to browse between effects.

Delay

Echo-like effect that repeats the sound.

• KNOB X — Length (time between repetitions)
• KNOB Y — Feedback (number of repetitions)

Reverb

Simulates acoustic space, from a small room to a cathedral.

• KNOB X — Length (room size)
• KNOB Y — Color (filter: darker ↔︎ brighter)

Distortion

Overdrives your sound for warmth and grit.

• KNOB X — Drive (overdrive amount)
• KNOB Y — Color (filter + resonance)

Chorus

Thickens and spreads the sound by multiplying the signal.

• KNOB X — Modulation (rate of movement)
• KNOB Y — Feedback (prominence of effect)

Filter

Removes high or low frequencies to shape your sound.

• KNOB X — Cutoff (turn left to cut highs, right to cut lows)
• KNOB Y — Resonance (emphasizes the cutoff frequency)

Compressor

Controls dynamics — punch down loud parts, bring up the overall volume.

• KNOB X — Drive (input gain into compressor)
• KNOB Y — Speed (how fast the compressor reacts)

Punch-In FX 2.0

Hold FX while playing, then press pads to trigger real-time performance effects. These are pressure-sensitive and can be combined by pressing multiple pads.

Live input FX

Process external audio through the built-in effects:

1. Press MAIN.
2. KNOB X — Input gain.
3. KNOB Y — Internal FX send level.

Plug an instrument into the line-in and turn up the send to hear it through whichever FX is selected.

Output / master compressor

Press SHIFT + FX to access the master compressor.

• KNOB X — Drive
• KNOB Y — Speed

Sidechain

Press + while in the output settings to access sidechain compression.

Sidechaining on K.O. II uses note triggers to engage the compressor — you can trigger it even without sound, and choose the exact length and shape.

Timing & Quantization

Note interval

Press TIMING, then turn KNOB X to select the note interval:

Swing

Press TIMING, turn KNOB Y to adjust swing. Applies to 1/8 and 1/16 intervals only.

Quantize vs. free time

Press TIMING, then use − / + to toggle:

• − (Quantize) — Snaps recorded notes to the grid
• + (Free Time) — Records exactly as you played

Note repeat

Hold TIMING + press a pad to repeat it at the current note interval.

Timing correct

Press SHIFT + TIMING to open timing correct. Quantize individual pads or notes without affecting the whole pattern.

Loop

Press SHIFT + TEMPO to create a loop (inspired by the OB-4’s magic radio).

How-To Guides

Enable velocity sensitivity

1. SHIFT + ERASE → system settings.
2. Navigate to PAD → VEL (or type 301 for high, 302 for low).
3. Press ENTER to confirm.
4. Press MAIN to return.

Change the scale in keys mode

1. Press KEYS to enter Keys mode.
2. SHIFT + ERASE → system settings.
3. Navigate to PAD → SCA (or type the code directly).
4. Choose your scale and press ENTER.
5. Hold KEYS + a pad to transpose the root note.
6. Hold KEYS + − / + to change octave.

Available scales: 12-tone (310), Major (311), Minor (312), Dorian (313), Phrygian (314), Lydian (315), Mixolydian (316), Locrian (317), Major Pentatonic (318), Minor Pentatonic (319).

Turn on the metronome while playing

1. SHIFT + ERASE → system settings.
2. Navigate to SEQ → MET → ON (code 400).
3. Press ENTER.
4. Press TEMPO, turn KNOB Y to set metronome volume.
5. Press PLAY to hear it.

Resample a chord

1. In SOUND mode, select a sound and assign it to a pad.
2. Press MAIN, select the pad, press KEYS.
3. Press SAMPLE, then + until the display shows RSP (resample).
4. Press a group pad to choose the destination.
5. SHIFT + pad to engage hands-free sampling.
6. Go back to the group with your sound and play the chord.
7. Press SAMPLE to stop recording.

Copy / paste

Copy a bar or pattern

Copy sounds

Erase operations

Fader assignments

Hold FADER and select from the options printed above the pads:

• Level (default), Pan, FX Send, Pitch, Attack, Release, Filter Cutoff, Filter Resonance, and more.

Recording fader automation

• Live: Hold RECORD + move FADER.
• Step: Hold RECORD + move FADER to write the fader position to the current step (latching).
• Reset: SHIFT + FADER resets the virtual fader position for all assignments in the current group. Press again to undo.

System Settings

Press SHIFT + ERASE to access system settings. Navigate with − / + and ENTER, or type a numeric code directly and press ENTER.

MIDI settings

Sync settings

Pad settings

Sequencer settings

Shortcuts & Key Combinations

Mode access

Recording & transport

Editing

Navigation

Performance

MIDI Reference

MIDI note map

Each group maps to a 12-note range. In default (non-keys) mode:

In Keys mode, the full range 0–127 is available.

Pad-to-note mapping (Group A example)

Groups B, C, and D follow the same pad layout, offset by one octave each.

MIDI implementation

Sync & Connectivity

Syncing two K.O. II units

1. Set both units to 1/16 sync (in and out).
2. Connect sync out on one unit to sync in on the other with a 3.5 mm cable.

Syncing a Pocket Operator to K.O. II

1. Connect K.O. II sync out → Pocket Operator input jack.
2. Set the Pocket Operator to SY2 (press function + BPM button).
3. On K.O. II: System settings → SYN → OUT → 8 (code 210).
4. Press play on the PO first, then PLAY on K.O. II.

Syncing K.O. II to a Pocket Operator

1. Use a 3.5 mm stereo-to-2× mono cable.
2. Stereo end → PO output. Right channel → K.O. II line-in. Left channel → K.O. II sync-in.
3. Set PO to SY1.
4. On K.O. II: System settings → SYN → IN → 8 (code 200).
5. Press play on PO, then PLAY on K.O. II.

Syncing with vintage drum machines

1. Connect drum machine sync out → K.O. II sync in (may require a 3.5 mm to DIN sync cable).
2. On K.O. II: System settings → SYN → IN → 24 (code 202).
3. Press play on both devices simultaneously.

To send clock to a drum machine, connect K.O. II sync out → drum machine sync in and set SYN → OUT → 24 (code 212).

MIDI keyboard control

1. Connect via 3.5 mm TRS MIDI cable (or USB via a MIDI host).
2. K.O. II auto-detects incoming MIDI (MIDI icon or USB icon lights up).
3. Play the keyboard to trigger pads directly.
4. Press KEYS to play one pad transposed across the keyboard.

Sequencing external MIDI devices

1. Connect K.O. II MIDI out → external device MIDI in.
2. In Sound Edit (MIDI page), set a pad’s MIDI channel with KNOB X.
3. Set root note with KNOB Y.
4. Notes played or sequenced on that pad now send MIDI to the chosen channel.

USB-C

The USB-C port provides:

• MIDI over USB (device mode)
• Clock and transport over USB
• Sample transfer via EP Sample Tool
• Firmware updates
• Power (5V / min 1A)

Technical Specifications

Audio

Connectivity

Power

Troubleshooting

Error codes

Formatting the drive

If you see a filesystem error code (E.05, E.10–E.12):

1. Power off the device.
2. Hold SHIFT + ERASE, then power on.
3. The drive will be formatted — all sounds and projects will be erased.
4. Update to the latest firmware afterward.

Factory reset (erase drive)

To completely wipe the device and start fresh:

1. Hold SHIFT + ERASE on startup.
2. FMT will display for about 10 seconds, then the unit boots with all content removed.

Lock mode

To prevent accidental changes during performance:

• Hold MAIN on startup to enable lock mode.
• LOK displays briefly.
• Any changes made will reset when the device is restarted.

Common issues

Firmware updates

Keep K.O. II up to date via the update utility at teenage.engineering. Connect via USB-C and follow the on-screen instructions.