ActiveThree: 128-channel, DC amplifier, 24-bit resolution, biopotential measurement system with Active Electrodes

Active3 is the next generation of biopotential measurement systems for scientific research. The Active3 its cutting-edge SAR analog-to-digital converter technology offers perfect noise spectrum with total absence of spurious tones. BioSemi's third-generation active electrodes and amplifier system - the ActiveThree - combines extremely high signal quality, portability, low power consumption, and ease of use.

The ActiveThree can come configured with up to 142 channels of EEG/EXG electrodes and sensors. All 142 channels are fully DC-coupled and equipped with a novel 24-bit SAR (successive approximation register) A/D converter. This is the latest ADC technology available on the market, allowing for the highest signal quality with high interference suppression, offering a clean frequency spectrum. New low-voltage components further allow for low power consumption compared to its predecessors. As a result, a much smaller-sized battery is used, leading to a decrease in both the size and weight of the main AD-box. Additionally, the battery can be purchased anywhere locally, as it is a standard single battery cell. Auxiliary sensors such as respiration belts, GSR/EDA sensors, and response switches are now automatically detected and configured by the system. Last but not least, the CMS/DRL circuitry has improved in interference suppression.

Headcap system with the fastest application time. Up to 128+8 electrode + 6 sensor channels in a single ultra compact box.
Reliable measurements without skin preparation. Third generation active electrode: integrated HF filter, reduced power consumption.
Battery powered front-end with fiber optic data transfer. Flexible colored electrode labeling system.
Suitable for EEG, ECG as well as EMG measurements. 24 bit ADC per channel, SAR ADC conversion!!
Graphical programming (LabVIEW) on PC and Linux. Improved digital resolution, LSB value is 31.25nV.
Full range of auxiliary sensors available. Full DC operation, large input range (400mVpp).
    Sample-rate 16 kHz/channel, optional downsampling in software.
Active Electrodes & Headcaps
USB2 Receiver
Active3 Advertorial
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ERP measurement example
CNV measurement example
ABR measurement example

  Discontinued BioSemi systems:
ActiveTwo First commercially available active electrodes system with 24 bit resolution, model 2001/2023.
ActiveOne First commercially available system with active electrodes, 16 bit resolution, model 2000/2001.
Mark-8 Mains/battery powered System for passive electrodes, model 1998/1999.
Mark-6 Battery powered System for passive electrodes, model 1996/1997.

Note: For research applications only. Not a medical device as defined in EU directive 93/42/EEC. Not designed or intended to be used for diagnosis or treatment of disease.