Hardware

1. Introduction #

Every living organism is alive with subtle electrical and physiological activity. A beating heart, a contracting muscle, changing skin conductivity, the slow electrical rhythms of plants, and the dynamic responses of fungi all reflect living processes unfolding moment to moment. Although these signals are normally invisible, they can become a rich source of creative expression. THE SOURCE is a wearable biophysical measurement and interaction platform developed by bioMECI that enables artists, performers, designers, and researchers to work directly with these living signals

2. General Description #

Designed to bridge scientific instrumentation and artistic practice, THE SOURCE safely measures biological activity and transforms it into expressive control signals that can shape sound, video, lighting, kinetic sculpture, immersive environments, and interactive installations.

THE SOURCE was developed for sensing living systems, including human physiology – such as ECG (heart activity), EMG (muscle activity), EEG (brain activity), respiration, skin conductance, and temperature. The same measurement principles also extend naturally to plants and fungi. All living systems generate measurable electrical and physiological dynamics that change in response to their internal state and surrounding environment. By making these subtle processes available in real time, THE SOURCE invites artists to explore new forms of collaboration with the living world.

Definitions: THE SOURCE is a data acquisition platform that consists of hardware (THE SOURCE device), software (embedded device firmware and VST3 plugin), and accessories.

3. THE SOURCE Device Core Features #

Biopotential signal input supports a full range of human, fungi and plant electrical signals (gain range of 20 to 20,000)
Transducer signal input supports a large range of physical signal input types: pressure, force, strain, temperature, PH, electrodermal activity, conductivity, electric field, respiratory effort, blood volume pulse, etc. (gain range of 1 to 1000)
DC-500Hz signal bandwidth (max), can be further filtered via analog and/or digital means
Dual pipe (analog and digital) signal processing design, analog and digital processing paths run in parallel
Theoretical minimum latency possible via analog signal processing pipeline, output signals can be routed directly to sound systems or other interfaces
Extremely low latency digital signal processing pipeline – behaves as a high-performance computer sound card
Digital pipeline data can be converted to analog for real-time and control applications
All data pipelines can be converted to Amplitude Modulation output to support wireless transmission and direct external sound card data collection of multiple, sub-audio range, physiological signals
Local headphone driver output
12-bit ADCs sampling up to 48 kHz per channel – downsampled to 2kHz
USB composite interface (UAC2 Audio + CDC Serial) and wireless OSC (via ESP32 bridge)
Real-time feature extraction and filtering in firmware
OLED graphical interface for live signal and status display
Designed for integration with Max/MSP, TouchDesigner, Unity, and Ableton Live
Designed to support multi-channel, tightly synchronized, group physiology measures (people, fungi, plants) via Amplitude Modulation output
Built-in biopotential differential instrumentation amplifier actively boosts common-mode input impedance to reduce interference
Built-in transducer amplifier
Electrically isolated front-end for human-subject safety

3.1. Isolation Description #

THE SOURCE device employs layered electrical isolation to protect users and ensure high signal fidelity.
Safety and Isolation Architecture:

Biopotential and transducer inputs and stimulus outputs (subject connections) are galvanically isolated from all computer (USB) and external I/O (Rx/Tx/Modulation/Headphones/Line)
Leakage current: adheres to IEC 60601-1 for Type BF applied parts)

3.2. Grounding and Isolation Strategy #

All user-connected analog circuits (Applied Parts) are electrically isolated relative to the computer host and external equipment. A combination of optical and transformer based methods are employed to adhere to applicable safety standards of IEC60601-1. External equipment (computer and audio equipment) grounds are isolated from THE SOURCE device subject connections.

4. Firmware Details and Description #

Firmware is developed in C/C++ for RP2040 (dual-core MCU), using TinyUSB and FreeRTOS. Firmware modules are structured for low-latency biophysical signal acquisition and high-throughput streaming. Firmware updates are uploaded via .uf2 firmware files that are available through the
bioMECI support team.

4.1. Core Functional Blocks #

Analog Signal Processing: Instrumentation amplifier, transducer amplifier, selectable gain and filtering stages, multiple analog outputs (modulation output, headphone output, line output).

Acquisition Engine: Multi-channel DMA-driven ADC sampling at 48 kHz, downsampled to 2kHz in the digital pipeline.

Digital Signal Processing: DC offset correction, IIR/biquad filters, RMS and envelope computation, HRV and EDA metrics.

Data Transport:

USB-CDC for ASCII/binary serial streaming
USB-Audio (UAC2) for two-channel real-time biopotential streaming
OSC (UDP) via ESP32 bridge for wireless interaction

User Interface: SH1107 128×128 OLED for real-time waveform display, connection state, and menu navigation.

System Control: Bootloader supports firmware updates via USB drag-and-drop (UF2).

4.2. Operational Modes #

Performance Mode (STD)– low-latency OSC/Audio streaming for live systems
Research Mode (ADV) — timestamped recording with full-resolution data.
Diagnostic Mode (DEV) — calibration and hardware self-test interface

4.3. Firmware Update #

To put THE SOURCE device into firmware mode, plug the USB into your computer while THE SOURCE device is off.

Press down the THE SOURCE device firmware button (the one by the top of the device on the left – just above the three buttons)
While holding it down, turn on the THE SOURCE device
A removable drive named RPI-RP2 appears on the computer screen. (similar to
when you load a removable drive)
Copy or drag the .uf2 firmware file onto the RPI-RP2 drive
The drive will automatically disconnect, and THE SOURCE device will restart
using the new firmware

5. Intended Use #

THE SOURCE is a two-channel biosignal and transducer signal acquisition and signal processing platform designed for research, education, creative practice, human-computer interaction, and experimental applications. It acquires physiological signals from compatible sensors and provides real-time visualization, recording, analysis, and routing of these signals to supported software and hardware.

THE SOURCE is intended for use by researchers, artists, designers, educators, students, developers, and other users exploring biosignal-based interaction and data acquisition.

THE SOURCE is not a medical device. THE SOURCE is not intended for the diagnosis, treatment, prevention, mitigation or cure of disease. THE SOURCE should not be used for human life-support applications.

6. Safety and Handling #

Please read these instructions before using THE SOURCE.

General Safety

THE SOURCE platform is intended only for research, educational, creative, and experimental use. THE SOURCE is not a medical device and is not intended for the diagnosis, treatment, prevention, mitigation or curing of disease.
Do not use THE SOURCE as a substitute for professional medical advice or equipment.
Use only as described in the documentation.

Electrical Safety

Use only the supplied or recommended USB power source and accessories.
Do not expose the device to water, excessive moisture, or conductive liquids.
Disconnect power immediately if the device becomes unusually hot, emits smoke, or shows signs of damage.
Do not attempt to disassemble, modify, or repair the device. There are no user-serviceable parts inside

Sensor Connections

Connect only approved sensors and accessories designed for use with THE SOURCE device.
Inspect cables and connectors before use. Replace damaged cables immediately.
Never force connectors into ports.
Disconnect sensors before cleaning the device.

Human Use

If using electrodes or other sensors on the body, apply them only as directed in the supplied instructions.
Do not place electrodes or other sensors on broken, irritated, or infected skin.
Stop using the device if you experience discomfort, skin irritation, or an unexpected reaction.
Consult a healthcare professional if irritation persists.

Operating Environment

Operate the device in a clean, dry environment.
Avoid exposure to extreme temperatures, direct sunlight, excessive dust, vibration, or corrosive chemicals.
Keep the device away from strong electromagnetic fields and sources of static electricity.

Cleaning

Disconnect the device from power before cleaning.
Wipe the device enclosure with a soft, slightly damp cloth.
Do not use abrasive cleaners, solvents, or aerosol sprays.
Do not allow liquids to enter any device openings or connectors.

Storage

Store the device in a cool, dry location.
Protect it from impacts and excessive pressure during transport.
Avoid storing the device in vehicles or other locations subject to extreme heat or cold.

Children

THE SOURCE device and accessories are not toys.
Keep the device, cables, and accessories out of reach of young children.

Disposal

Dispose of the device and electronic accessories in accordance with local regulations for electronic waste (e-waste).
Do not dispose of electronic equipment in household garbage where prohibited.

6.1. Contraindications #

Do not use THE SOURCE:

In situations where distraction could create a safety hazard.
As a substitute for certified medical equipment.
In applications where device failure could result in injury or loss of life.

Users with implanted medical devices (such as pacemakers, implantable defibrillators, neurostimulators, or similar equipment) should consult their physician before using any externally connected physiological sensors.

6.2. Improper Use #

Improper use of THE SOURCE may result in damage to the device or connected equipment. bioMECI Ltd. is not responsible for damage or injury resulting from misuse, unauthorised modification, or operation outside the recommended specifications.

7. Regulatory Notice #

THE SOURCE is a laboratory-focused instrumentation platform used for data measurement. THE SOURCE device and Accessories are CE marked and conform to all applicable standards – including the Low Voltage Directive and Electromagnetic Emissions and Immunity. THE SOURCE device also conforms to applicable IEC60601-1 electrical safety standards.

8. Liability #

THE SOURCE is provided as a research and creative technology platform. bioMECI, Ltd. shall not be liable for any damages resulting from improper installation, misuse, unauthorised modification, operation outside published specifications, or use contrary to the instructions provided in this manual. Users assume responsibility for the safe and appropriate operation of the device in their specific application.

9. Warranty #

9.1. Release Notice #

THE SOURCE is in the early stage of commercial release. Users may occasionally encounter minor hardware, firmware, software, or compatibility issues. Please communicate these concerns (if any) to info@biomeci.com to help resolve them.

9.2. Limited Hardware Warranty #

bioMECI warrants that THE SOURCE platform hardware will be free from defects in materials and workmanship under normal and intended use for a period of one (1) year from the date of delivery to the original purchaser. During the warranty period, bioMECI will, at its discretion, repair or replace hardware determined to be defective. Replacement products or components may be new or functionally equivalent refurbished components.

Warranty service requires proof of purchase and prior authorisation from bioMECI. Products must not be returned without receiving a Return Material Authorisation number and shipping instructions.

The warranty does not cover:

Accidental damage, misuse, neglect or improper handling.
Liquid exposure, excessive heat, improper storage or environmental damage.
Damage caused by an unsuitable power source, charger or connection.
Unauthorised opening, modification, repair or reverse engineering of the
physical unit.
Damage caused by third-party accessories not approved by bioMECI.
Normal cosmetic wear, scratches or enclosure discolouration.
Normal reduction in rechargeable-battery capacity over time.
Disposable electrodes and other consumable materials.
Data loss, experimental outcomes or interruption of research activities.
Compatibility problems caused by later changes to third-party operating
systems, plug-in hosts or software platforms.
Use for medical diagnosis, treatment, clinical monitoring or any purpose outside
the documented intended use.

10. Specifications #

10.1. System Specifications #

Parameter	Value (metric)
Dimensions (L x W x H)	130 mm × 95 mm × 35 mm
Weight	135 g
Enclosure Material	Laser sintered / 3201PA-F Nylon
Mounting / Wear Options	One-wrap Velcro strap, adjustable, for waist or arm or pole mounting
Cable Length (electrode leads)	1 meter (nominal)
Internal Power Source	3.7 V, 2000 mAh Li-ion rechargeable
Battery Life	~12 hours continuous operation
Charging Interface	USB-C, 5 V @ 500 mA nominal

10.2. Inputs #

Sampling Specifications.

ADC Resolution: 12-bit
Sampling Rate: 48 kHz (downsampled to 2kHz)
Biopotential Input Noise (typ.): <1 µV p-p (<350nV rms)

Input Type	Channels	Input Range	Input Impedance	Connector Type	Description
Biopotential (ECG/EMG/ EEG, etc.) Input	1 differential protected to +/- 25V	±80 uV 40nV resolution gain = 20,000 to ±80 mV 40 uV resolution gain = 20	10 MΩ differential CMII boosted 2 GΩ	1.5 mm safety connections for electrode leads (Standard)	Low-noise, differential input with active common-mode drive and RFI / static protection
Auxiliary Analog Input	1 single-ended protected to +- 25V	±1.6 mV 800nV resolution gain = 1000 to ±1.6 V 800mV resolution gain = 1	1 MΩ	3.5mm stereo phone jack for plug-in external sensors	For external sensors (respiratory effort, blood volume pulse, electrodermal activity, acceleration, field, temperature, force, strain, pressure, light, etc.)
Battery Monitor (internal)	1	Typical for 3.7 V Lithium-ion	–	–	On-board ADC for power management

10.3. Outputs #

Output Type	Voltage Range / Level	Output Impedance	Connector Type	Description
Audio Line Output	±1.8 V max ±1 V nominal (nominal at 0 dBV)	50 Ω	3.5 mm TRS differential output	Provides conditioned or mixed biophysical signal output
Headphone Output	±1.8 V max (8 Ω load)	Drives 8-32 Ω Headphones	3.5 mm TRS differential or mono output	Real-time auditory feedback or monitoring
Modulation Output	0-2v p-p (adjustable) 4.096 kHz carrier	100 Ω	3.5 mm TRS mono output	For compatibility with generic external audio devices (sound cards, wireless transmitters)
Isolated Stimulus Output	0-3.3 V analog or digital	100 Ω	3.5 mm TRS mono output (electricallyisolated)	Body-safe stimulus or analog feedback channel
USB / Serial Data (Tx/Rx)	3.3 V logic	TTL/CMOS	USB-C	USB-CDC (serial) and UAC2 audio streaming
Modular 6P6C Receptacle Digital I/O and Analog output	3.3 V logic	TTL/CMOS	6P6C Modular Cable	UART (Rx/Tx) Serial, battery power (3.7V), and analog audio differential drive output

*Image 1.1 – THE SOURCE device’s input and output diagram.*

AUX OUT – 3.5mm stereo plug (tip: 3.3V, ring: Output, shield: G).
Output for sample-accurate (synchronised) stimulus, trigger and test signals. +/- 1V nominal output range.
AUX IN – 3.5mm stereo plug (tip: 3.3V, ring: Input, shield: G).
Input for SOURCE transducers. +/- 1.6 V to +/- 1.6 mV single-ended max input ranges – over gains of 1 to 1000
ELECTRODE LEADS IN – (1.5mm female – touchproof).
Connect three (3) electrode leads (IN+ Lead / IN Reference Lead / IN- Lead). +/- 80mV to +/- 80uV differential voltage max input ranges (IN+ to IN-) – over gains of 20 to 20,000.
6P6C I/O
Modular 6P6C connector for accessory modules and expanders, UART (Tx/Rx), Differential Analog Driver Output (mimic of LINE OUT), and Protected Battery Power Output (3.7V).
USB-C
Power, charging, and USB Data I/O.
MOD OUT – Modulation Output – 3.5mm stereo plug (tip: Mod Output, ring: N/C, shield: G).
4kHz (4.096kHz) amplitude-modulated output for sound card interfacing – AC Coupled. +/- 1 V nominal output and adjustable range (0-2 V p-p)
PHONE OUT – Headphone Drive Output – 3.5 mm stereo plug (tip: L, ring: R, shield: G).
L and R are differential analog driver outputs from THE SOURCE device – Headphone driver outputs are AC – coupled. +/- 1V nominal output range.
LINE OUT – Line-level Drive Output – 3.5 mm stereo plug (tip: L, ring: R, shield: G).
L and R are differential analog line driver outputs from THE SOURCE device. Line-level driver outputs are DC – coupled. +/- 1V nominal output range.