Help Center

1. File Format and Track Length Restrictions
   • File Format: Only single-track MIDI files are supported; other music formats are not supported.
   • Track Length: When playing via the app, each song is limited to a maximum of 30 minutes (to prevent insufficient storage space on the mobile device). No length restriction applies when playing directly from a computer DAW.
   • Storage Method: During live performance, audio files can be stored in the music box’s internal memory or read via a USB flash drive (for easy on-the-fly adjustments and changes before performances).

2. Musical Range Restrictions
   • N20 Range: Full notes from C3 to A5, equivalent to the white keys of a piano (excluding semitones/black keys).
   • N40 Range: F2 to A6, excluding F#2, G#2, A#2, and C#3.
     (Middle C = C3 = 261.6 Hz).

3. Maximum Polyphony
   Refers to the maximum number of notes that can be struck simultaneously:
   • N20 Model: Maximum polyphony of 7 notes.
   • N40 Model: Maximum polyphony of 10 notes.

4. Playback Speed Limits
   • For Different Pitches: If the melody consists of notes that leap (not repeated same pitch), Muro Box’s playback speed is virtually unlimited. It only takes 0.001 second to process different pitches. Even at an extremely fast tempo of ♩= 375 BPM with 1/64th notes (the smallest unit in the app), Muro Box can still play. Dense chromatic runs like those in “Flight of the Bumblebee” need not worry about missed notes.
   • Repeated Note Limit (Same Pitch): Due to the mechanical return time of the note comb, a single pitch cannot be struck more than five times per second, i.e., a maximum of 300 strikes per minute. When a song’s tempo ♩ ≥ 75 BPM and consecutive sixteenth notes (same pitch) are played, note dropouts may occur. In such cases, it is recommended to delete one of the repeated notes.

5. Motor Speed Selection
   In the app, tap the gear icon at the bottom right, go to “Settings” > “Music Box Settings” to adjust the motor speed percentage:
   • High Speed: Smoother playback, less timing drift, but louder motor noise.
   • Low Speed: Quieter motor noise, but rhythm stability is more susceptible to melodic variations.

6. Latency
   • Fixed Latency (~100ms): When playing from a computer DAW, due to the physical structure of the music box, there is a fixed delay of approximately 0.1 seconds from receiving a MIDI signal to actual sound production (equivalent to one sixteenth note at 120 BPM). If playing together with other instruments, it is recommended to send the MIDI signal 100ms earlier (pre-delay) in the sequencing software to align the beat.
   • Motor and clutch mechanics can cause slight torque fluctuations during playback, resulting in a random backward shift of up to 20ms in note timing (similar to a swing feel).
   • Startup Latency: When starting from a stop, the motor requires “warm-up time” to spin up from zero, so sound does not begin immediately. (In MIDI Controller mode, as the motor remains continuously spinning in standby, this latency does not occur.)

7. Volume and Live Sound Reinforcement Recommendations
   Muro Box’s acoustic output level is comparable to a traditional paper-roll music box, not a large grandfather clock-style music box. If performing together with other instruments or in public settings, it is advisable to use an external microphone to capture the sound and amplify it through speakers to ensure the music box is not masked by other instruments.

The N40’s range is downward compatible with the 40, 30, 20, and 15 notes music boxes, including the Muro Box-N20. So, any compositions created for the N20, whether by you or other customers, can be directly played on the N40.

For a complete illustrated guide, please refer to the detailed tutorial on APP composition and settings.

1. Create a New Composition: On the APP home page, tap the pen and staff icon in the bottom menu to enter “My Creations.” Then tap the “+” icon in the upper right corner and select “Freestyle Composition.”

2. Song Information Settings:In the composition settings page, you can configure the song photo, track name, description, style, rhythm, tempo, visibility (public/private), and whether comments are allowed. When selecting the range, ensure it corresponds to your Muro Box model (e.g., 20-note or 40-note) so that the notes you compose fall within the playable range of the music box.

3. Edit Notes:Enter the piano roll composition interface. You can tap directly on the grid squares to add or delete notes (tap again to delete). Press and hold a note to adjust its position.

4. Save: After completing the note arrangement, tap the settings icon in the upper right corner. You can freely modify the track name, tempo (BPM), and sharing permissions. Finally, press “Save” to finalize your custom composition.

(For a complete step-by-step tutorial with screenshots, please refer to the detailed guide on importing MIDI from iPhone.)

1. On your iPhone, open the email containing the MIDI file. Tap the MIDI file attachment below the email body, then tap “Save to Files.” Save it to “Downloads” under “On My iPhone,” tap “Save” in the top-right corner, and exit the Mail app.

2. Open the Muro Box app. Tap the pen and staff icon in the bottom menu to enter “My Creations,” then tap the “+” icon in the top-right corner. Select “Import MIDI from my phone,” find the MIDI file you just saved, and tap it.

3. On the arrangement settings page, you can configure: song cover image, song title, description, style, tempo, speed, whether to make it public, and whether to allow comments.
   • The system will automatically apply the tempo embedded in the MIDI file.

   • Note: If the imported melody exceeds the note range of your Muro Box (N20/N40), notes falling outside the range will be automatically ignored.

(For a complete step-by-step guide with screenshots, please refer to Detailed Tutorial: Importing MIDI Files on Android)

1. Download a MIDI File from an Email Attachment
   Open the email containing the MIDI file on your Android phone. Tap the MIDI file attachment below the email body to download and save it to the phone’s built-in “Download” folder. Then exit the email app.

2. Open the Muro Box App and Import the MIDI File
   Open the Muro Box app, tap the pen and staff notation icon at the bottom to enter “My Creations,” then tap the “+” icon at the top right. Select “Import MIDI from phone,” navigate to “Downloads,” find the MIDI file you just saved, and tap it.

3. Configure Song Information
   After successful import, you can set the following on the arrangement editing page: song cover image, song title, description, style, tempo, speed, whether to make it public, and whether to allow comments. Once confirmed, save.
   • The system will automatically adopt the tempo embedded in the MIDI file.

   • Please note: If the imported melody exceeds the range of your Muro Box (N20/N40), notes outside the range will be automatically ignored and not played.

(For a complete illustrated tutorial and detailed steps on importing a file from Google Drive, please refer to Import MIDI from URL – Full Guide)

1.  Copy the full URL of the MIDI file. Then open the Muro Box APP, tap the “pen and staff” icon in the bottom menu to enter “My Creations” – tap the “+” icon in the upper right corner, and select “Import MIDI from URL.”

2.  In the pop-up input field, long press and “paste” the URL you just copied, then tap “Confirm.” Once the system successfully retrieves the audio file, a save screen will appear. After the import is complete, you can set the song photo, song name, description, style, tempo, speed, whether to make it public, and whether to allow comments in the arrangement settings page. Confirm the settings are correct and then save.
   • The system will automatically adopt the tempo embedded in the MIDI file.

   • Please note: if the imported melody exceeds the note range of your Muro Box (N20/N40), notes outside the range will be automatically ignored and will not be played.

For a complete step-by-step guide with screenshots, please refer to the Export Guide.

1. Open the Muro Box App and tap the “pen and staff” icon on the bottom menu. On the right side of the song you wish to export, tap the “three dots” menu button, and select “Export Song.”

2. Export Format
   – MIDI: Suitable for further editing in other music software.
   – PDF / DXF: These file formats allow you to print the paper strip for hand-punching on traditional punched-paper music boxes.

3. After selecting the desired file format, tap “Confirm Export.”

4. Please note:
   • If you composed a 20-note melody using the Muro Box App, select PDF – Grand Illusion 20 when exporting. Its musical scale range matches that of the Muro Box N20.

   • If you composed a 40-note melody, please note that there is currently no paper strip that fully supports the 40-note range. The closest available option is Grand Illusion 30 . After export, any notes beyond the 30-note range will not be printed on the paper strip.

(For a complete illustrated tutorial, please refer to the Android Bluetooth MIDI input device pairing guide.)

Please note: Muro Box supports BLE MIDI starting from firmware version 1.2. Also note that your phone must have a special app installed to enable BLE MIDI.

1. Download and install the “Piano MIDI Bluetooth” app from Google Play.

2. Open the app, and tap the Bluetooth icon on the top toolbar.

3.  Select “Start scan”. Make sure location services are enabled on your phone so that Bluetooth can discover the Muro Box. If the music box is found, the option “MUROBOX-MIDI” will appear. In the “Select MIDI mode” menu, choose “Controller” and press OK.

4. Play notes on the on-screen keyboard, and the music box will start playing.

(For complete illustrated instructions, please refer to “Pairing the MIDI Input Device with the Muro Box via Bluetooth for iPhone Users“)

Please note: Muro Box supports BLE MIDI starting from firmware version 1.2 or later. Also note that your phone must have a special app installed to support BLE MIDI.

1. Search for and install the “MIDI Recorder with E. Piano” app from the App Store.

2. Open the app and tap the Bluetooth icon on the bottom toolbar.

3. Select MIDI mode. If the music box is detected, the option “MUROBOX-MIDI” will appear. Tap and hold it for a few seconds; once the status shows “Connected,” the connection to the music box is established.

4. Tap “Record” on the bottom toolbar. Play notes on the keyboard displayed on the screen, and the music box will start playing in real time.

(For complete illustrated instructions, please refer to the Muro Box Programmable Music Box MIDI Input User Guide)

• Computer DAW Software (USB-C / DIN 5)
  1. Use a USB-C cable to connect the computer to the Muro Box.

  2. In the DAW software, select Muro Box as the MIDI Output device.

  3. Note: The N40 also supports DIN 5 MIDI cables; the corresponding switch must be activated.

• MIDI Keyboard / MIDI Instrument (Real-time Performance)
  1. Connect the MIDI keyboard to the Muro Box via USB-C or DIN 5.

  2. Once powered on, you can play the music box directly.

  3. Mobile Devices or Wireless Devices (BLE MIDI)

• Pairing via Apps or Devices That Support BLE MIDI
  1. After a successful connection, MIDI signals can be transmitted wirelessly to control playback.

  2. Recommended Apps:
     • iPhone: MIDI Recorder with E.Piano

     • Android: Piano MIDI Bluetooth USB

• The Muro Box supports standard MIDI input, making it compatible with most DAW software and MIDI devices, allowing greater freedom in composition and performance.

Since the music box has physical range limitations, MIDI files downloaded from the internet often require fine-tuning. If you have basic sheet music reading skills, you can try editing them yourself!

Please read the [Complete Guide to Adjusting MIDI Files for the Muro Box Music Box]. This article demonstrates how to edit MIDI files using the free MuseScore software to adjust pitch range and rhythm, so the result can be played on the Muro Box music box.

(For a complete illustrated tutorial and detailed steps , please refer to Listen to or Import Songs from Music Box Maniacs (MBM) in the Muro Box App)

1. On your computer, visit the MBM website (Music Box Maniacs).

2. Click “Explore” at the top, then select songs that match the note range of the N40 or N20 from the “All-types” dropdown menu. The number indicates the note range: the N40 can play songs with up to 40 notes, and the N20 can play songs with up to 20 notes. Filter for songs that fit your music box’s range, then click into the song page.

3. Click “Export” in the upper-right corner of the song, then select “Muro Box.” A QR code for the song will appear on the screen.

4. Open the Muro Box app, tap the “pen and staff” icon in the bottom menu to enter “My Compositions,” tap the “+” icon in the upper-right corner, then select “QR code” to scan the computer screen.

5. Configure song information: After successful import, you can set the song photo, title, description, genre, rhythm, tempo, visibility (public/private), and whether comments are allowed in the arrangement settings page. Confirm and save.

(For a complete step-by-step guide with screenshots, please refer to Importing MIDI via File Sharing.)

1. Open the communication app or any application on your phone where the MIDI file is stored. Tap the file to open it, then tap the system’s built-in “Share” or “Open in another app” icon (usually a square with an upward arrow or a share link symbol).

2.  In the share menu that appears, tap the “Muro Box” icon. Your phone will switch to the Muro Box app and display an import window. Confirm your song details, then tap “Save” to complete the import.

• A MIDI keyboard controller looks similar to an electronic keyboard but does not produce sound on its own. It must be connected to a Muro Box or another sound source device. Any controller that supports MIDI functionality is generally compatible with the Muro Box.

• Choose based on the number of keys:
  • 32 keys: Suitable for entering melodies and portability. Covers nearly the entire N20 range (missing only the highest note). If a note goes out of range during playing, use the octave shift buttons to adjust the range.

  • 49 keys: Fully covers both the N20 and N40 range. If you intend to play with both hands simultaneously, a 49-key or larger controller is recommended.

  • 61 keys: Commonly used in arrangement work. If you also create music with software like Logic Pro or Cubase, consider this size.

• This is the MIDI keyboard (61 keys) we use in our office for testing music boxes. Reference link:https://24h.pchome.com.tw/prod/DMAFCT-A9008EH6K

1. Keep the microphone at a distance (avoid contact recording): Placing the microphone directly against the wooden casing amplifies motor noise. It is recommended to use an external microphone and maintain an appropriate distance to fully capture the room’s natural reverberation.
   For reference, please see the official sound quality comparison video:
   https://www.youtube.com/watch?v=y50cW11zRPY

2. Lightweight equipment and simple post-processing:

   Lavalier microphone: Position a small microphone (e.g., Boya Lav) in front of the sound hole, and apply noise reduction plugins (e.g., Brufsi) during post-processing to reduce mechanical noise. Musician Shwan’s test:
   https://www.youtube.com/watch?v=bRDALSQmCfo

   Handheld recorder: Use a portable recorder (e.g., Zoom H2) for audio capture, then apply noise reduction software and EQ adjustments during post-processing to minimize motor noise. Musician Christophe’s test:
   https://www.youtube.com/watch?v=kGFHOOBNx6k

The motor of the music box does produce some noise. However, every unit undergoes a full functional inspection before shipping, including checks for unwanted sounds, so all units meet our shipping standards. Regrettably, the motor noise cannot be completely eliminated.

Motor noise is indeed one of the current challenges for Muro Box. At present, the only way to reduce motor noise is to lower the motor speed through the app. The default factory setting is 85% speed. When the speed is reduced, the motor noise also decreases, but the rhythm of the music may become slightly unstable, giving it a “swing-like” feeling. Therefore, adjustments must be made based on actual usage.

The mechanical design of the N20/N40 music boxes has already reached its current structural limit. Although the motor sound can be heard, during playback it is not as prominent behind the melody. This is also part of the unique characteristic of a mechanical music box being “alive.”