Bitbrain Diadem 12-channel EEG

The Bitbrain Diadem is a 12-channel wearable dry-EEG system designed for portable data acquisition in real-world research settings. It supports fast setup and wireless recording, with coverage of prefrontal, frontal, parietal and occipital regions.

For full instructions, consult the official guide:
Diadem 12ch EEG User Guide (EN, v.2025)

Image © Bitbrain Technologies S.L. Used for documentation and identification purposes.

Overview

Diadem is a portable dry-EEG device that integrates 12 EEG sensors, plus ground (GND) and reference (REF), mounted on an adjustable headband based on the 10–10 international system. The system uses active shielding and optimized DRL to improve signal quality during mobile use. Data can be streamed via Bluetooth and simultaneously stored on a microSD card.

The device is intended for research purposes only and is not a medical device.

Video Guide: Placement and Setup

EEG Channels and Layout

The headband includes 12 dry EEG sensors positioned according to the 10–10 system:

AF7, Fp1, Fp2, AF8
F3, F4
P3, P4
PO7, O1, O2, PO8

Reference (REF) is located on the ear clip.
Ground (GND) is integrated in the headband.

Technical Specifications

Sampling rate: 256 SPS, 24-bit
Battery life: > 8 hours
Charging time: ≤ 3 hours
Data transmission: Bluetooth 2.1 + EDR (≈ 10 m line-of-sight)
Local storage: Removable microSD card, up to 8 GB, Class ≥ 10
Data format: .sdf (conversion via software)
Nominal voltage: 3.7 V
Nominal power: 750 mW
Integrated sensors: IMU (accelerometer, gyroscope, magnetometer)
Amplifier dimensions: 71 × 71 × 34 mm
Amplifier weight: 120 g
Head perimeter: 530–610 mm
Certification: CE (Directive 2014/53/EU)

System Components

The standard kit includes:

Amplifier with 12 channels (internal battery)
EEG headband with 12 dry sensors + GND + REF
Headband stand
8 GB Class-10 microSD card with SD adapter
Battery charger with adapters

Optional accessories (via auxiliary input):

Elastic adjustable band (arm or waist mounting)
Photodiode EEG
Button box (1-bit trigger)
Pedal (1-bit trigger)
TTL trigger (Bitbrain or external)
Duplexer (photodiode + trigger)

Setup Summary

1. Power and Preparation

Ensure the amplifier battery is charged.
Do not use the device while charging.
Turn on the amplifier using the power button.
The Bluetooth LED flashes while connecting and remains steady when paired.
Low battery is indicated by the battery LED.

2. Connectivity and Recording

Pair the device via Bluetooth (version 2.1 or higher).
The Bluetooth device name corresponds to the amplifier serial number.
Data can be streamed to the computer and saved to the microSD card at the same time by enabling SD card record in the software.

Placement Summary

Open all side and top adjustment strips.
Place the headband on the head, aligning the front central mark with the nose.
Ensure the frontal strip is horizontal and flat sensors contact the skin directly.
Attach the ear clip (REF) to the left earlobe.
Gently rock mobile sensors so pads slide through hair and contact the scalp.
Wait approximately 10 seconds after each adjustment for signal stabilization.

Detailed placement steps and diagrams are provided in the user guide.

Recording and Signal Quality

EEG signals are displayed in real time in the acquisition software.
Sensor color indicates relative contact impedance.
If impedance is high:
Adjust headband zones evenly on both sides.
Re-position mobile sensors carefully.
Allow time for signal stabilization after each change.

Battery and Power Handling

Disconnect the charger once the battery is fully charged.
Do not store the device long-term with the battery at 100% charge.
Store the device in a dry environment between 5 °C and 40 °C.
Use only the charger provided by Bitbrain (maximum 1 A).

Cleaning and Maintenance

Clean and disinfect the headband after each use, according to user guide instructions.

More Information

Manufacturer: Bitbrain Technologies S.L., Zaragoza, Spain