MIDI2 Monitor MK2 – Freeware

A real-time MIDI 1.0 and MIDI 2.0 (UMP) monitor for macOS — free from AmeNote.

MIDI2 Monitor MK2 watches every MIDI message flowing into your computer — whether it’s coming from a classic MIDI 1.0 keyboard or a native MIDI 2.0 (Universal MIDI Packet) device — and shows you exactly what’s happening, decoded into plain English instead of raw hex.

Who it’s for: Musicians and studio engineers troubleshooting a MIDI setup, educators demonstrating how MIDI 2.0 works, developers verifying their own implementations, and anyone who wants to actually see (or hear) what their MIDI devices are sending.

Key features:

  • Live decoding of MIDI 1.0 and MIDI 2.0 (UMP) traffic — plain-English descriptions of every message, not just hex dumps.
  • Extended Message Data decoding — Note On/Off Attribute Data is interpreted using the relevant MIDI-CI Profile (Piano, Orchestral Articulation, Drums), and Flex Data messages (tempo, time signature, metronome, key signature, chord name, performance text) are decoded too.
  • Built for accessibility — an extensive text-to-speech narration system reads messages aloud, with per-device voice selection and stereo pan control, adjustable speech rate/volume, an audible “tick” on message arrival, and a spoken 10-second catch-up review — usable independently of the visual display. It’s useful for everyone, including blind and low vision musicians and engineers. The T key toggles assistive speech modes.
  • Per-device control — a Devices panel lets you enable/disable individual MIDI sources, and assign each its own voice and pan, useful when several devices are connected at once. Open multiple windows to monitor devices separately.
  • Focus filters — hide System Active Sensing or MIDI Clock noise, or restrict monitoring to true MIDI 2.0-native connections only, so you see just the messages that matter.
  • Export to CSV for offline analysis, plus a configurable rolling message buffer (500 / 1,000 / 5,000 messages).
  • No data collection — MIDI2 Monitor MK2 runs entirely locally and doesn’t transmit anything from your computer.
  • Free.

MacOS Requirements: macOS 15 (Sequoia) or later. macOS 27 (Golden Gate) or later is recommended for best MIDI 2.0 experience.

DOWNLOAD FOR MACOS

Windows Requirements: Windows 11 version coming soon.

Installing MIDI2 Monitor MK2

  1. Click the download button above to download MIDI2_Monitor_MK2_v1-2.dmg.
  2. Once downloaded, double-click the .dmg file to open it.
  3. A window will appear showing the MIDI2 Monitor MK2 icon and a shortcut to your Applications folder. Drag the MIDI2 Monitor MK2 icon onto the Applications shortcut to install it.
  4. Open your Applications folder and double-click MIDI2 Monitor MK2 to launch it.

About the security warning

The first time you open MIDI2 Monitor MK2, macOS will likely show a warning saying it “cannot verify the developer” or the app is from an “unidentified developer”, or “Apple could not verify…”. This is expected — MIDI2 Monitor MK2 isn’t yet notarized by Apple, so macOS shows this caution. To open it anyway:

  1. Open System Settings → Privacy & Security, scroll down to the Security section, and click Open Anyway next to the message about MIDI2 Monitor MK2. This button only appears for about an hour after step 2.
  2. Enter your Mac password if asked, then click Open to confirm.

You only need to do this once. After that, the app opens normally.

License

Use of MIDI2 Monitor MK2 is governed by the End User License Agreement below. You’ll also be asked to accept this same agreement the first time you launch the app.

MIDI2 Monitor MK2 — End User License Agreement Effective Date: August 25, 2026

This End User License Agreement (“Agreement”) is a legal agreement between you (“you” or “User”) and AmeNote Inc. (“AmeNote”, “we”, “us”, or “our”) concerning your use of the software application MIDI2 Monitor MK2, including any associated documentation and updates that AmeNote makes available to you (collectively, the “Software”).

By installing, copying, accessing, or using the Software, you agree to be bound by this Agreement. If you do not agree to these terms, do not install or use the Software.

1. License Grant Subject to your compliance with this Agreement, AmeNote grants you a limited, non-exclusive, non-transferable, non-sublicensable license to install and use the Software for your personal or internal business purposes. The Software is provided to you free of charge. This license does not transfer to you any ownership interest in the Software or in any intellectual property rights associated with the Software.

2. Ownership and Intellectual Property The Software is licensed, not sold. AmeNote and its licensors retain all right, title, and interest in and to the Software, including all copyrights, trademarks, trade secrets, patents, and other intellectual property rights. Except for the limited license expressly granted in this Agreement, no rights are granted to you, whether expressly, by implication, estoppel, or otherwise. “MIDI”, “MIDI 2.0”, and related terminology and marks may be trademarks or intellectual property of their respective owners. Nothing in this Agreement grants you any rights in such marks.

3. Restrictions You may not, except to the extent that applicable law expressly permits you to do so: sell, rent, lease, sublicense, or otherwise commercially distribute the Software; redistribute, publish, mirror, host, or make the Software installer or other copies of the Software available for download by others; modify, adapt, translate, or create derivative works of the Software; remove or alter copyright, trademark, or other proprietary notices; reverse engineer, decompile, disassemble, or otherwise attempt to derive the source code of the Software; or use the Software to develop or distribute a competing software product where doing so involves unauthorized copying or use of AmeNote’s proprietary code or intellectual property. The foregoing restrictions do not apply to the extent that a particular restriction is prohibited by applicable law and cannot legally be waived. You may provide others with a link to an official AmeNote website or other official distribution location where the Software is made available. You may not independently redistribute the Software installer.

4. Apple Software and Operating System Interfaces The Software is designed to operate on supported Apple platforms and may use application programming interfaces, frameworks, system services, and other technologies provided by Apple Inc. Your use of the Software does not grant you any rights to Apple’s software, services, trademarks, or other intellectual property. Your use of Apple products and services remains subject to the applicable terms and conditions of Apple Inc. AmeNote does not represent or warrant that the Software will remain compatible with any particular version of macOS or with any particular Apple hardware or technology.

5. No Data Collection or Transmission by AmeNote The Software does not collect personal information or telemetry for transmission to AmeNote and does not transmit information from your computer to AmeNote as part of its normal operation. The Software is intended to operate locally on your computer. This provision does not apply to information that you independently choose to provide to AmeNote, such as when contacting AmeNote for technical support.

6. Technical Support The Software is provided without technical support. AmeNote does not undertake any obligation to provide installation assistance, troubleshooting, user assistance, documentation updates, bug fixes, compatibility assistance, or other technical support for the Software. AmeNote may, at its sole discretion, provide information, documentation, FAQs, community resources, or other assistance relating to the Software, but any such assistance is provided voluntarily and does not create an obligation to provide ongoing or future support. Nothing in this section limits any mandatory consumer rights or remedies that cannot lawfully be excluded or limited under applicable law.

7. Updates and Changes AmeNote may, at its discretion, develop and release updates, modifications, new versions, or replacements for the Software. AmeNote is not obligated to provide updates, upgrades, technical support, or continued availability of any particular version of the Software. AmeNote may discontinue distribution or support of the Software at any time. Any update or new version may be subject to additional or different license terms, which will be presented to you when applicable.

8. Intended Use The Software is intended primarily as a MIDI monitoring, testing, development, and diagnostic tool. The Software is not designed or intended for use in safety-critical systems or applications where failure, malfunction, interruption, delay, or inaccurate operation of the Software could reasonably be expected to result in death, personal injury, or significant property or financial damage. You agree not to rely upon the Software for such purposes.

9. Disclaimer of Warranties TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, THE SOFTWARE IS PROVIDED “AS IS” AND “AS AVAILABLE”, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE. To the maximum extent permitted by applicable law, AmeNote disclaims all warranties and conditions, including any implied warranties or conditions of merchantability, fitness for a particular purpose, title, non-infringement, accuracy, reliability, availability, and quiet enjoyment. AmeNote does not warrant that: the Software will meet your requirements; the Software will operate without interruption; the Software will be error-free; defects will be corrected; the Software will be compatible with any particular computer, operating system, MIDI device, MIDI implementation, or other hardware or software; or information displayed by the Software will always be complete, accurate, or reliable. You are responsible for determining whether the Software is suitable for your particular purposes.

10. Limitation of Liability TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, AMENOTE INC. AND ITS DIRECTORS, OFFICERS, EMPLOYEES, CONTRACTORS, AND LICENSORS SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES, OR FOR ANY LOSS OF DATA, REVENUE, PROFITS, BUSINESS, BUSINESS OPPORTUNITY, GOODWILL, OR OTHER ECONOMIC LOSS, ARISING OUT OF OR RELATING TO THE SOFTWARE OR THIS AGREEMENT, EVEN IF AMENOTE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. To the maximum extent permitted by applicable law, AmeNote’s total aggregate liability arising out of or relating to the Software or this Agreement shall not exceed CAD $10. The limitations in this section apply regardless of the legal theory on which a claim is based, including contract, tort, negligence, strict liability, or otherwise. Nothing in this Agreement excludes or limits liability, rights, remedies, or obligations that cannot lawfully be excluded or limited under applicable law.

11. Indemnification To the maximum extent permitted by applicable law, you agree to indemnify and hold harmless AmeNote Inc. and its directors, officers, employees, and agents from claims, damages, liabilities, costs, and expenses arising from your unlawful use of the Software or your material violation of this Agreement. This provision does not apply to the extent that the applicable claim results from AmeNote’s own conduct or from circumstances for which applicable law does not permit indemnification to be required.

12. Termination Your license under this Agreement automatically terminates if you materially violate any provision of this Agreement. Upon termination, you must cease using the Software and delete all copies of the Software in your possession or control. Sections concerning ownership, intellectual property, disclaimers, limitations of liability, governing law, and any provisions that by their nature should survive termination shall survive termination.

13. Governing Law and Jurisdiction This Agreement shall be governed by and construed in accordance with the laws of the Province of Alberta and the federal laws of Canada applicable therein, without regard to conflict-of-law principles. Subject to the rights described in Section 14 and to any other applicable mandatory law, the courts located in the Province of Alberta, Canada shall have exclusive jurisdiction over disputes arising out of or relating to this Agreement or the Software. Nothing in this section prevents AmeNote from seeking urgent or equitable relief in any jurisdiction where such relief may be necessary to protect its intellectual property or other rights.

14. Consumer Rights If you are a consumer, nothing in this Agreement is intended to exclude, restrict, or limit any mandatory rights or protections that apply to you under the laws of the jurisdiction in which you reside and that cannot lawfully be excluded or limited by agreement. In particular, if applicable law provides you with mandatory consumer rights or remedies, those rights and remedies remain unaffected by this Agreement. If any provision of this Agreement is determined to be unenforceable or invalid as applied to a consumer in a particular jurisdiction, that provision shall be enforced to the maximum extent permitted by applicable law, and the remainder of the Agreement shall remain in effect.

15. International Use The Software may be downloaded or used in countries other than Canada. You are responsible for complying with all laws applicable to your use of the Software in your jurisdiction. Nothing in this Agreement is intended to require you to waive mandatory rights that cannot lawfully be waived in your jurisdiction.

16. Severability If any provision of this Agreement is determined to be invalid, illegal, or unenforceable, that provision shall be interpreted or modified to the minimum extent necessary to make it enforceable, where legally permitted. If it cannot be made enforceable, it shall be severed from the Agreement, and the remaining provisions shall continue in full force and effect.

17. No Waiver A failure by AmeNote to enforce any provision of this Agreement shall not constitute a waiver of AmeNote’s right to enforce that provision or any other provision in the future.

18. Entire Agreement This Agreement constitutes the entire agreement between you and AmeNote concerning the Software and supersedes all prior or contemporaneous agreements, understandings, and representations concerning the Software, except for separate written agreements expressly entered into by AmeNote.

19. Contact If you have questions concerning this Agreement or the Software, please contact: AmeNote Inc. — Alberta, Canada Website: https://amenote.com/

© 2026 AmeNote Inc. All rights reserved.