This page is read from MIDI Instrument Definitions, a Python library used in the author's other projects, in which every number is traced to a document its maker published. Its source is on GitHub.

Waldorf Iridium MK2 MIDI implementation

The MIDI implementation of the Waldorf Iridium MK2: what it answers to, and the 16 controls it offers, on firmware 4.0.3.

At a glance

Firmware: This page describes firmware 4.0.3.
MIDI channel: Not recorded.
MPE: Received: its voices are spread across its MIDI channels, a note to each.
Parts: Layer, 4 of them: each on a MIDI channel of its own, taking notes and controls.
Voices: 16, shared by the parts that play notes.
Note range: Not recorded.
Velocity: Received. Release velocity is received.
Aftertouch: Channel pressure and polyphonic, each answered.
Pitch bend: 12 semitones, and the range can be changed.
Program change: Received.
MIDI clock: Received.
Start and stop: Not recorded.
Control change: Assigned by the player, apart from the 16 controls below.
NRPN: None.
System exclusive: Not recorded.

Controls

In the order the definition gives them, by group. Under each control is the name a program calls it by, once pymidiinstrumentdefs.load("waldorf/iridium_mk2") has loaded them.

Controllers

Control	CC	Values
Wheel `wheel`	1	0-127 Received, never sent
Breath Control `breath_control`	2	0-127 Received, never sent

Pedals

Control	CC	Values
Expression `expression`	11	0-127 Received, never sent
Pedal `pedal`	64	0-127 Received, never sent

Modulation sources

Control	CC	Values
CC 22 `cc_22`	22	0-127 Received, never sent
CC 23 `cc_23`	23	0-127 Received, never sent
CC 24 `cc_24`	24	0-127 Received, never sent
CC 25 `cc_25`	25	0-127 Received, never sent
CC 26 `cc_26`	26	0-127 Received, never sent
CC 27 `cc_27`	27	0-127 Received, never sent
CC 28 `cc_28`	28	0-127 Received, never sent
CC 29 `cc_29`	29	0-127 Received, never sent
CC 30 `cc_30`	30	0-127 Received, never sent
CC 31 `cc_31`	31	0-127 Received, never sent

MPE

Control	CC	Values
MPE Y Axis `mpe_y_axis`	74	0-127 Received, never sent

Master

Control	CC	Values
Master Volume `master_volume`	7	0-127 Received, never sent

Where these facts come from

Source documents

Iridium MK2 User Manual, Rev. 1, dated 29 April 2026, its user manual, read on 10 October 2026 (the file read).
Iridium User Manual, Rev.3, dated 28 January 2026, its user manual, read on 3 October 2026 (the file read).
Iridium MK2 Spec, dated 5 March 2026, specification, read on 10 October 2026 (the file read).
Iridium Desktop MK2 – Waldorf Music, its product page, read on 10 October 2026 (the file read).
Iridium MK2 – Waldorf Music, one of its maker's support articles, read on 10 October 2026 (the file read).

How they were read

THE IRIDIUM MK2'S OWN MANUAL, WITH ITS SPECIFICATION SHEET, ITS PRODUCT PAGE AND THE FAQ IT LINKS. The 236-page Iridium MK2 User Manual comes inside Manual.zip, the archive the product page's Manual link serves; a second link serves Specifications.zip, holding a three-page specification sheet. None of the MK2's documents is a MIDI implementation chart, and the manual has no control map, because most parameters are reached by MIDI Learn: "Set: opens a page allowing you to link a desired MIDI CC connection to any panel parameter dial, potentiometer, or button." (manual p. 200). So control_change is learned. No page gives the numbers Learn accepts: the nearest range printed, "CC 1 to CC 118 (or Off)" (manual p. 185), belongs to the XY pad's own CC X/Y selector, and the Maps screenshot on p. 200 shows CC 0 mapped. The FAQ page adds that "the assignment is valid globally for all patches." (faq_page). The product page is titled Iridium Desktop MK2, and Waldorf's menus list no other MK2 Iridium, although the manual says once that the Tempo dial is Iridium MK2 Desktop only (manual p. 199).

SIXTEEN CONTROLLER NUMBERS ARE THE INSTRUMENT'S OWN. Fourteen are in the modulation-source table on p. 220, where five rows name a number: "Modulation wheel (CC #1)" (manual p. 220), "MIDI Sustain pedal (CC #64)" (manual p. 220), "MIDI Expression pedal (CC #11)" (manual p. 220), "MIDI Breath Controller (CC #2)" (manual p. 220) and "MIDI CC #22 - #31" (manual p. 220). The fifteenth is the MPE Y axis, "Front-back / Y-axis (sent as MIDI CC 74)" (manual p. 198); the number is printed only in the MPE section, and the table's MPE Y Axis row gives none, so recording it among the controls, as waldorf/iridium does, is this definition's reading. The sixteenth is the MK2's alone: "Hint: Master Volume reacts on MIDI CC #7." (manual p. 162), on the Master page, a sentence the Iridium's manual never prints; there, CC 7 is only a row in a screenshot of somebody's mappings (iridium_manual p. 203). The ten in the block are 22 to 31, written out here because the page prints only the ends.

ALL SIXTEEN ARE RECORDED AS RECEIVED, for the Iridium's reason: each is something the engine is modulated by, or answers to. What the manual says is sent is the panel - "All Panel parameter dials and pots are capable of sending MIDI Controller data via USB and MIDI Out." (manual p. 22) - and "Send CC: here you can activate all mapped MIDI Control Change (MIDI CC) data being sent out for the panel pots, buttons, and encoder." (manual p. 199), the mapped, learned numbers. The panic gesture sends one message by name, "to send an All Notes Off message." (manual p. 17), without saying whether it leaves the MIDI outputs. The arpeggiator and the sequencer send notes: "Keep in mind that the arpeggiator and the step Sequencer will send MIDI notes for enabled MIDI outputs." (manual p. 199).

IT SENDS NRPN AND DOES NOT ANSWER TO IT, as the Iridium does: "Send NRPN: if set to On, the physical panel elements send out MIDI NRPN data. For parameter automation please use MIDI CC as before. Keep in mind, that the Iridium MK2 does not react on incoming NRPN MIDI data." (manual p. 199). So nrpn: none.

FOUR LAYERS, ONE POOL OF SIXTEEN VOICES. "Iridium MK2 offers a multi-timbral sound mode which means that up to 4 different sound patches can be played simultaneously either as layered, split or independent Multi sounds." (manual p. 22), and "Keep in mind that all sound layers will share the maximum polyphony of 16 voices." (manual p. 22). Each Layer has its own channel in both directions - "Layer 1…4 Input Channel" (manual p. 197) and "Chan 1…4: here you can determine the MIDI channel for Layer 1, 2, 3, and 4 on which MIDI data is sent out." (manual p. 199) - so the four are one part, channel: assigned. No page says which channels the Layer menus offer: the glossary's "MIDI Channels 1 through 16 are available for this purpose." (manual p. 230) closes its definition of a MIDI channel in general. So no range is recorded, as for the Iridium. A learned controller reaches the Layer on its channel: "Make sure that you’re sending the CCs on the correct MIDI channel so that you change the values on the correct layer." (faq_page). The In page's screenshot shows a row of four channels for each input, DIN, USB Ctrl and USB Cmp (manual p. 197), so a Layer's channel appears to be set port by port. One setting decides which Layer the play controls reach in Split and Layered modes: Controller "Determines which Layer will be affected by incoming Mod wheel, Pitch bend, Aftertouch, Pads and Modulation pad data." (manual p. 164) - all of them, one, or the selected one. And in Single mode the layers "cannot be played together." (manual p. 163).

MPE, WITH AN OPTIONAL SECOND ZONE. "Left-right / X-axis (sent as MIDI Pitch Bend)" (manual p. 198), "Front-back / Y-axis (sent as MIDI CC 74)" (manual p. 198) and "Pressure / Z-axis (sent as MIDI Channel Aftertouch)" (manual p. 198). It is switched on input by input, and a controller's MPE configuration messages "will automatically put Iridium MK2 into MPE mode." (manual p. 198); "Iridium MK2 supports an optional second MPE zone" (manual p. 198). So per_voice_channels: true.

MIDI 2.0, OVER USB. "We implement MIDI 2.0 capabilities on both USB ports" (manual p. 202), falling back to MIDI 1.0 where the other side does not agree; "We have implemented UMP message types 1 (MIDI 1UP), 2 (System), 3 (SysEx), 4 (Channel Voice), and 15" (manual p. 202), the last for streaming messages, and only Management CI. Each USB port can be held to the older protocol: "If you want to use only the MIDI 1.0 protocol, you can activate it for the corresponding USB port." (manual p. 201). It receives per-note pitch bend: "We are supporting receiving per-note pitch bend messages in a similar way like in MPE mode." (manual p. 203), which is also a modulation source, "MIDI 2.0 Pitch Bend per Note" (manual p. 220). The format describes MIDI 1.0 and has no field for any of this; the specification sheet and the product page say "MIDI 2.0 compatible" (specification p. 2), and these paragraphs are what that means here.

VELOCITY ON AND OFF, AND POLYPHONIC AFTERTOUCH, ALL RECEIVED. The modulation sources include Velocity and Release Velocity, which the table describes as "MIDI Velocity" (manual p. 220) and "MIDI Release Velocity" (manual p. 220), so release velocity is answered to. The Iridium's manual names it only among the kinds of unipolar source, "Velocity; Release Velocity; Aftertouch (Pressure; and Polyphonic Pressure)." (iridium_manual p. 149), and its table has no such row. Aftertouch: "Here you can select, how the Iridium MK2 reacts on incoming polyphonic aftertouch MIDI messages: The default setting Poly AT interprets the aftertouch in a polyphonic way." (manual p. 167). Channel pressure is answered too: the MPE Z axis is channel aftertouch (manual p. 198), and p. 148's list of unipolar sources names "Aftertouch (Pressure; and Polyphonic Pressure)" (manual p. 148), though the table on p. 220 has only polyphonic pressure. This desktop has pads and a touchscreen rather than a keybed - "To play the Iridium MK2 you need a MIDI master keyboard." (manual p. 10) - and the manual says nothing of sending pitch bend, aftertouch or velocity, so this definition records none of them as sent. The sheet's "Wheels touchscreen for MIDI controls like mod wheel, pitch bend, aftertouch and velocity" (specification p. 2) describes on-screen controls and does not say they transmit.

PITCH BEND PER OSCILLATOR: "Determines the intensity of the pitch wheel in semitones for the selected oscillator from -24 to +24." (manual p. 31), with "Set Default: sets PB Range to its default value +12." (manual p. 31). Twelve is recorded, and that it can be set. Bend that arrives per note has a range of its own: "Per-Note Pitch Bend messages could arrive either from MPE mode or via MIDI 2.0 from respective sources." (manual p. 33), set once for all three oscillators from 12 to 96 semitones, or Off or External, and Off by default (manual p. 33); p. 203 agrees, "It has its own range setting" (manual p. 203). The MPE section on p. 198 still says the X axis works "with the range set using the PB Range for the corresponding oscillator" (manual p. 198), the Iridium's wording. The two cannot both be right for MPE, and neither is recorded: pitch_bend is the channel's.

CLOCK IS RECEIVED, AND NO PAGE SAYS MIDI CLOCK IS SENT: "MIDI Clock automatically syncs to incoming MIDI Clock if it is sent by an external device like a sequencer or drum machine." (manual p. 199). The one sentence about sending it is a denial: "Internal means that Iridium MK2 doesn’t react to incoming MIDI Clock, nor does it send MIDI Clock." (manual p. 199). The clock the MK2 does send is on a jack of its own, for "a huge range of vintage devices" (manual p. 207): "The Clock Out jack sends signals to an external device so that it can be synchronized to the Iridium MK2 tempo clock." (manual p. 207). The product page lists it as "Analog clock In & Out with clock divider settings" (product_page), so it is not MIDI, and clock stays receives.

THE SPLIT SENTENCE IS CORRECTED HERE: "The lowest setting is note C-2; the highest is note G8." (manual p. 164), where the Iridium's prints "The lowest setting is 0 (note C-2); the highest is 60 (note C8)." (iridium_manual p. 171) against its own "the middle C3 is note number 60" (iridium_manual p. 200). It bounds a split point, not the engine's range, so no note_range is recorded.

SOMEBODY'S SETTINGS, NOT A FACTORY MAP. The MIDI Maps screenshot on p. 200 shows CC 0, 2, 3, 4 and 5 mapped to named parameters, and the XY tab's on p. 185 sets the pad's axes to CC 9 and CC 2. Both are pictures of settings a player makes - the Maps page is the MIDI Learn store, as the Iridium's is, and the pad's numbers are chosen from "CC 1 to CC 118 (or Off)" (manual p. 185) - and nothing beside either says otherwise. CC 2 in both is the breath controller's number in the table on p. 220, and the manual does not say what happens when one number is both. Not recorded.

PROGRAM CHANGE IS RECEIVED, ON ONE FAQ ENTRY THE THREE IRIDIUMS SHARE. The manual names it only in its glossary (manual p. 231). The FAQ page the product page's FAQ link opens is the Iridium's FAQ: each of its 22 entries is on the Iridium's product page too, under the same author and time stamp, and one describes a setting this manual does not have, Apply Split to MIDI under Global/MIDI/Inputs (faq_page). The Iridium Core's FAQ shares the same entry. It reads: "This device does not react to Program Change Messages!" (faq_page), then "You will have to use the Favorites list in order to get the Prog CH working." (faq_page) and "This device uses only to the entries in the Favorites lis when Prog CH messages are used. As soon as you have put the most needed patches there, you can call them up by MIDI." (faq_page) - the maker's own uses only to and lis. Every entry is titled as a user's question or complaint and answered in its body, so receives: true is read as waldorf/iridium reads the same words, and the three Iridiums answer the question the same way. A support page is a source that should confirm a fact rather than carry it alone, and only a picture confirms this one. No text of the manual or the quick start guide says what program change does, but the Favorites screenshot on p. 172 labels each filled slot with a MIDI number, from 0001 [MIDI 1] to 0007 [MIDI 19], as the Iridium's and the Core's manuals do. The number follows the slot, not the patch - 0005 is [MIDI 9] - and matches the slot's place in the Set counted from 0, row by row, which is this definition's reading. A slot numbered for MIDI is what the FAQ describes. The picture names no message, and the entry was written for the family rather than for this instrument, so it is carried for the Iridium's reason, and doubted here. No preset count is recorded: the Favorites hold "20 sound patches per Set" (manual p. 171) over twelve Sets, "which means faster access to 240 sound patches" (manual p. 171), and nothing says whether program change reaches one Set or all twelve. Nothing says the MK2 sends program change: the Iridium Keyboard sends it from its Macro buttons, an action called Send MIDI Prog (iridium_manual p. 194) under the heading The Macro Buttons (Iridium Keyboard only) (iridium_manual p. 193), and this manual has no such action.

NOT RECORDED: the channel range; mode; transport, the only start input being the CV Start In jack (manual p. 207), one of the "Analog gate and start inputs" (product_page); system exclusive over MIDI 1.0, the UMP SysEx type being all that is said; and a note range.