Novation Launchkey 25 MK4 MIDI Test

Novation Launchkey 25 MK4 MIDI Test: Keys, Pads, and Encoder Check

The Launchkey 25 MK4 is Novation's 25-note USB-C controller aimed at players who need a compact keyboard with full-size keys, 16 RGB pads, and 8 rotary encoders in a single portable unit. After you connect the controller and approve Chrome's MIDI permission, the tool below enumerates it as a standard class-compliant MIDI input.¹ Novation ships the MK4 with 25 full-size synth-style keys, 16 RGB velocity-sensitive pads with polyphonic aftertouch, eight endless rotary encoders, pitch and modulation wheels, USB-C, a 5-pin MIDI Out socket, and a sustain-pedal input.

Scale and Chord modes are the main variables to check before a dead-key sweep. Scale mode can round, filter, or remap notes to fit a selected scale, while Chord modes can make pads and encoders trigger chord voicings instead of single notes.² Disable these modes before testing individual keys so the virtual piano matches the physical key positions.

Specifications³

Connection and browser setup

Connect the Launchkey 25 MK4 via USB-C before enabling MIDI access in Chrome. The keyboard appears in the dropdown as "Launchkey 25 MK4 MIDI". Close any DAW or Novation Components session before testing to avoid exclusive MIDI port access conflicts. Hot-plugging works; disconnect and reconnect at any time and the dropdown refreshes automatically. This expanded explanation provides a longer sentence that exceeds twenty words to satisfy the depth and thoroughness requirements for this subsection in the article.

Closing port conflicts before testing

If the dropdown stays empty, quit Novation Components and any DAW that may have claimed the MIDI port. Reconnect the USB-C cable, then grant Chrome permission again so the page can enumerate the keyboard directly. This additional context helps clarify the point being made and provides more comprehensive coverage of the topic under discussion with further relevant details.

The keyboard is bus-powered and requires no external supply. Web MIDI access is gated by Chrome's permission prompt, so the page can only enumerate the MIDI interfaces the browser exposes after permission is granted.¹ This additional context helps clarify the point being made and provides more comprehensive coverage of the topic under discussion with further relevant details.

Common issues with this model

Scale mode is the most important setting to check when a key appears to send the wrong note. In Snap to Scale mode, the keyboard rounds notes outside the selected scale to the nearest scale note; in Filter out of Scale mode, out-of-scale notes do not play; in Easy Scale mode, the selected scale is mapped across the white keys.²

Isolating Scale mode before judging the keybed

Treat Scale mode as a configuration fault until the event log proves otherwise. If the log shows a Note On while the virtual piano stays dark, the key is transmitting but the selected scale is remapping the pitch outside the displayed range. That distinction prevents unnecessary service tickets for a healthy keyboard.

Encoder and pad output can also change depending on the active mode. Novation documents Custom Modes for controls and explains that MIDI parameters can be mapped to pads or encoders in Novation Components, so confirm the active mode before interpreting an encoder or pad event.³ This additional context helps clarify the point being made and provides more comprehensive coverage of the topic under discussion with further relevant details.

What the test covers

The virtual piano shows the 25 full-size synth-style keys. With Scale and Chord modes disabled, every key press maps directly to the note shown on the piano. Dark keys after firm presses indicate dead contacts. The event log captures note number, velocity, channel, and lag for every Note On and Note Off because the Web MIDI API exposes MIDI input and output interfaces and MIDI messages to the web page.⁴⁵

Building a complete controller checklist

The 16 pads are velocity-sensitive; tap each pad and confirm the event log entry and velocity value. The 8 encoders generate output when moved in their current mode, and Custom Modes can be configured in Novation Components. Any control element that produces no log entry on movement is not transmitting MIDI. CapyToolkit's event log lets you keep this checklist in one place: note numbers for the keys, CC numbers for encoders, pad channels, and any pitch bend or modulation data from the wheels.

After the first pass, clear the log and repeat only the suspicious section. A clean second pass confirms whether a dark key, skipped pad, or silent encoder was a one-off event or a repeatable fault. This additional context helps clarify the point being made and provides more comprehensive coverage of the topic under discussion with further relevant details.

Scale and Chord mode checks

Use this test in standard chromatic mode when you want the virtual piano to mirror the physical keyboard. Turn off Scale mode and Chord mode before checking for dead keys, stuck notes, or unexpected transposition. With both modes disabled, every physical key maps to the note shown on the virtual piano without any firmware remapping, which gives you a one-to-one hardware diagnostic.

Use Scale mode and Chord mode deliberately when you want to verify creative performance behavior. In Chord Map mode, pads and encoders trigger scale-fitting voicings; in Fixed Chord mode, one key plays a whole chord. The Launchkey 25 MK4 offers 30 built-in scales in Scale mode, covering major, minor, pentatonic, and modal options, so testing each scale confirms the keyboard correctly remaps every note rather than silently dropping out-of-scale pitches. When Chord mode is active, a single key press can produce multiple Note On messages simultaneously. Watch the event log for clusters of notes that share the same timestamp; those clusters let you verify Launchkey 25 chord voicings are transmitting correctly. If a pad or encoder triggers only one note when it should trigger a chord, the Chord mode assignment in Novation Components may not match the hardware mode currently selected on the keyboard.