An always on midi capture solution.

The User Guide:

EchoBox is a hardware based MIDI recorder and looper for musicians.
How often have you sat and played the piano and had a creative moment grab you?
The next day you sit down to try to recreate that hook, but it has gone.

"I wish I'd recorded that!"

A laptop could help but screens and notifications kill creativity.

EchoBox is a passive listener, with minimal screen interactions, it sits waiting to be called to action, to echo back your ideas that it's been jotting down all along, not as audio but as perfect key presses, the volume, the expression pedals and for synths- those filter tweaks, all captured with minimal latency.

Concept, design, programming and assembly by Mischa Pakhomoff

Contents

• First Time Setup
• What's with the Buttons?
• Basic Operation
• Looping
• Seeking During Playback
• Display Information
• LED Colour Guide
• WiFi File Management
• Tips & Tricks
• Troubleshooting
• File Naming

What This Device Does

The EchoBox records your MIDI performances in real time and plays them back as seamless loops — all with four physical buttons, no computer required. The screen has been designed to be minimal, no menu diving, just enough to help, but not enough to hinder.

First Time Setup

1. Setting the Clock

EchoBox needs you to set the time and date so the timestamps are accurate. Set the clock once on first use via WiFi mode (see WiFi File Management for full details):

1. Hold + while powering on or when already on, LEDs glow blue at ~1 second, then flash blue 3×, when the lights are steady blue you are in Wifi mode.
2. Connect to WiFi echobox (password: midi1234)
3. Open http://192.168.4.1 → click "Set Device Time"
4. Press any button on the device to exit and reboot

Note: The clock is battery-backed (which will need changing one day!) and keeps time when the device is powered off.

2. Connect it to your midi device

EchoBox has two midi ports. The left port receives midi so should be connected to your midi device's midi out. The right port sends midi and should be connected to your midi device's midi in- this allows you to replay from EchoBox back to you device.

3. Power up

EchoBox is powered by USB-C, a regular phone power supply should do. WiFi can take a bit more power, so if you notice glitches in Wifi mode then use a higher power supply.

4. SD Card

There should be a high capacity SD card in the left hand opening, this can be removed when the unit is disconnected. However as there is WiFi connectivity for accessing all the files this can be avoided.

Understanding the Buttons

The device has 4 buttons, from left to right:

A — LOOP	B — PREV	C — PLAY	D — NEXT

Button Functions at a Glance

Button	While Idle	While Browsing	While Playing	While Recording
LOOP	Cycle loop mode	Cycle loop mode	⏹ Stop playback	No effect
PREV	No effect	⏪ Go back (−1, −2...)	⏪ Rewind 1s	No effect
PLAY	Enter browse mode	▶ Play selected track	⏹ Stop playback	End recording now
NEXT	No effect	⏩ Go forward	⏩ Skip forward 1s	No effect

LOOP Button

Cycles the loop mode. The colour shows the current setting:

PREV / REWIND Button

• While browsing: steps backward through recordings (−1, −2, −3...)
• During playback: jumps backward 1 second per press — press multiple times for a bigger jump

PLAY Button

• While idle: enter browse mode
• While browsing: start playing the selected track
• During playback: stop immediately
• During recording: end the recording right now (instead of waiting 5 seconds)

NEXT / FORWARD Button

• While browsing: steps forward through recordings, past 0 into uploaded files (+1, +2...)
• During playback: jumps forward 1 second per press — press multiple times for a bigger jump

Basic Operation

Recording Your First Loop

1. Set Loop Mode — Press (LOOP) until the LED is GREEN (infinite loop)
2. Start Playing — Play any MIDI notes. Recording starts automatically. All 4 LEDs turn red.
3. Stop Recording — Stop playing and wait 5 seconds (auto-saves), or press (PLAY) to stop immediately.
4. Loop Starts — Playback begins automatically and loops forever. Press or to stop playback.

Tip: The loop is seamless — there is less than 2ms of silence between iterations.

Playing Back a Previous Recording

1. Press (PLAY) — enters browse mode, LEDs turn green showing the newest recording

2. Press or to navigate:

3. Press (PLAY) again to start playback

4. Press or to stop

Seeking During Playback

While a track is playing you can jump to any position:

Press	Action
once	⏪ Jump back 1 second
three times	⏪ Jump back 3 seconds
once	⏩ Jump forward 1 second
three times	⏩ Jump forward 3 seconds

Any stuck notes are silenced automatically each time you seek. To stop playback entirely, press or .

Stopping Playback

Press (LOOP) or (PLAY) — both light red during playback as a reminder that they are stop buttons. All MIDI notes are silenced immediately.

Note: and seek through the track rather than stopping it.

Loop Modes Explained

Press (LOOP) to cycle through the three modes:

	Mode	Behaviour
● RED — Loop OFF	Record only	Saves the recording but does not play it back. Good for capturing performances you'll browse and play later.
● YELLOW — Loop ONCE	Play once	Plays the recording once after capture, then returns to idle. Good for quickly previewing what you just played.
● GREEN — Loop INFINITE	Loop forever	Loops continuously until you press or . Perfect for live performance. Each loop is seamless (less than 2ms gap).

Display Information

During Playback

PLAY Loop:INF
0:30/2:15
CH:05  42% T:0

While Browsing

SELECT Loop:INF
DUR: 2:13
RECORDING:0

Line 3 shows your current position: RECORDING:0 = newest recording, RECORDING:-3 = 3rd-most-recent, UPLOAD:+2 = uploaded file #2.

Screen Saver

After 30 seconds of no activity the display and LEDs turn off to protect the screen.

Any button press or incoming MIDI note wakes the device instantly.

LED Colour Guide

Loop Mode ( Button A, while idle)

Device State

Colour	When
● All four LEDs red	Recording in progress
● and red	Playback active — press either to stop
● All four LEDs green	Browsing your recordings (brighter = further back)
● All four LEDs purple	Browsing uploaded files
● All LEDs flash blue	Entering WiFi mode
● All off	Screensaver active

WiFi File Management

Use WiFi mode to set the clock, upload MIDI files, or manage your recordings.

Entering WiFi Mode

Option 1 — From idle (no power cycle needed):

1. While the device is idle, hold + for 2 seconds
2. LEDs glow blue at 1 second, then flash blue three times and reboot
3. The device boots directly into WiFi mode

Option 2 — At power-on:

1. Turn off the device
2. Hold + then turn on while holding

In both cases the display shows: Join echobox wifi / pw=midi1234 / 192.168.4.1

4. Connect to WiFi: echobox (password: midi1234)
5. Your browser should open automatically — if not, go to http://192.168.4.1

What You Can Do

Using Uploaded Files

Uploaded files appear as positive track numbers (+1, +2, +3...). Browse past 0 with (NEXT) to reach them. Blue LEDs indicate you are on an uploaded file. Play them exactly like your own recordings.

Exiting WiFi Mode

Press any button on the device — it reboots to normal mode.

Tips & Tricks

Quick Live Loop

1. Set loop to ● GREEN (press until green)
2. Start playing — recording starts automatically
3. Stop playing and wait 5 seconds
4. Loop starts immediately

Precise Recording Stop

Press (PLAY) during recording to end it at exactly the right moment, rather than waiting for the 5-second silence timeout.

Building a Set List

Upload your backing tracks as .mid files via WiFi. They appear as +1, +2, +3... Browse to them with (NEXT) and press (PLAY) to start.

Skipping Through Long Recordings

Press several times to skip forward quickly, to go back. Each press moves 1 second.

Entering WiFi Without Power Cycling

Hold + for 2 seconds while idle. The device reboots into WiFi mode — no need to unplug and replug.

Troubleshooting

"Nothing happens when I play MIDI notes"

• Check the MIDI cable direction: MIDI OUT → Device MIDI IN
• Check your MIDI controller is powered on
• Check the SD card is inserted

"Time is wrong on recordings"

• Hold + for 2 seconds while idle (or hold at power-on) to enter WiFi mode and set the device time
• If the time resets every power cycle, the backup battery may need replacing

"Display is blank"

• Screen saver is active — press any button or play a MIDI note to wake it
• Check the device is powered on

"Can't connect to WiFi"

• Make sure the device is in WiFi mode (display shows Join echobox wifi)
• Look for network name: echobox
• Password: midi1234
• Try forgetting the network on your device and reconnecting

"Uploaded MIDI file won't play"

• Make sure the file is standard MIDI single track format (.mid)
• Try re-uploading with a different channel selection
• Some complex MIDI files may not convert perfectly

File Naming

Recordings are named automatically with a sequence number, date, time, and MIDI channel:

Example: midi_00042_20260201_143022_CH05.txt

Files are stored on the SD card and can be copied to a computer at any time.

Safety Notes

✅	Recordings save to SD card automatically — nothing is lost if you power off
✅	Clock is battery-backed — timestamps survive power cycles
✅	No stuck MIDI notes — all notes are silenced when you stop or seek
✅	SD card is removable — plug it into your computer to back up files
✅	WiFi mode is read-only until you click delete
✅	+ WiFi shortcut only works while idle — no risk of triggering during recording

Build Journey

From first breadboard to finished device.

Nov 2025 — Early version before the PCB

Dec 2025 — Trying different connectors to gain space

Dec 2025 — Breadboard prototype with buttons

Jan 2026 — The custom PCBs arrive

Jan 2026 — PCB assembly

Jan 2026 — First working prototype with the PCBs

Mar 2026 — Components and modules

Mar 2026 — The 3D print enclosure graveyard

More from the build

Quick Reference

Button	Idle	Browsing	Playback	Recording
LOOP	Cycle loop mode	Cycle loop mode	⏹ Stop	—
PREV	—	⏪ Previous track	⏪ Rewind 1s	—
PLAY	Browse mode	▶ Play selected	⏹ Stop	End now
NEXT	—	⏩ Next track	⏩ Skip 1s	—

WiFi Mode: Hold + for 2s while idle, or hold at power-on · Network: echobox · Password: midi1234 · Address: http://192.168.4.1

Screen Saver: Display off after 30s inactivity · Press any button or play a note to wake.

Enjoy creating!

Concept, design, programming and assembly by Mischa@Pakhomoff.co.uk

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