ActiveThree AD-box "Unsurpassed EEG Signal Quality with Cutting-Edge SAR Technolog"

ActiveThree is the next generation of biopotential measurement systems for scientific research. ActiveThree's signal quality surpasses any EEG system currently available thanks to cutting-edge SAR analog-to-digital converter technology. BioSemi's third-generation active electrodes and amplifier system - the ActiveThree - combines unsurpassed signal quality, portability, low power consumption, and ease of use. ActiveThree can come configured with up to 128+8 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 and 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, temperature, GSR, plethysmograph 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.
The ActiveThree AD-box forms an ultra compact, low power galvanically isolated front-end (close to the subject). Each AD-box channel consists of a low noise DC coupled post-amplifier, with a first order anti-aliasing filter, followed by a SAR analog to digital converter, and decimation filter with a steep fifth order cascaded integrator-comb (CIC) filter response and high resolution 24-bit output. The digital outputs of all the AD converters (up to 128) are digitally multiplexed and sent to the PC via a single optical fiber without any compression or other form of data reduction.

SAR converter technology for an unsurpassed clean spectrum, linearity and dynamic range.
ActiveThree system Specs.
ActiveThree Pricing.
ActiveThree Accessories
Request info.
Autodetection of auxiliary sensors for increased ease of use.
Smaller form-factor AD-box allows for versatile and portable applications.
Improved CMS/DRL circuitry for high interference suppression.
Third-generation active electrode: unsurpassed signal quality and ultra-high S/N (signal-to-noise) ratio.
Active electrodes with Integrated high-frequency filter.
ADC per channel offers synchronized sampling, no skew, zero-reference principle.
24 bit sampling, 31nV digital resolution with guaranteed no missing codes.
Configurable/upgradeable number of channels: 8 up to 128 channels.

16 kHz sample-rate per channel.

Full DC operation, with input range as large as found in AC designs.
Battery powersupply with fiber optic link offers optimal interference rejection and subject safety.
Low power design: 10 hour battery life for 128 channels, 20 hours for 8 channels.
Special input stage matched with the output of the new 2-wire Active electrodes.  


128 channel AD-box with battery
8 channel Amplifier/Converter module
8 touchproofs for EOG,EMG, ECG.




All questions about the Active3 system


Auxiliary sensor inputs:
The auxiliary sensor inputs on the ActiveThree have been completely resigned with six highly versatile inputs. No matter the type of sensor, auxiliary sensors can selectively be connected to any of the six auxiliary inputs. ActiveThree auto-detects the connected sensor and transmits the correct configuration to ActiView acquisition software. ActiView automatically updates the display to show and record data from the connected sensors, without the need to manually configure the sensor. Available auxiliary sensors include: GSR/EDA electrodes Respiration belt Plethysmography (PPG) Temperature sensor (e.g., skin temperature) Response switch.
  - GSR/EDA electrodes
- Respiration belt
- Plethysmography (PPG)
- Temperature sensor (e.g., skin temperature)
- Response switch

Electrodes for Auditory Brainstem Response (ABR)
ABR (auditory brainstem response) electrodes interface directly with ActiveThree through the six universal auxiliary inputs. The ABR active electrode circuitry has been improved and now features lower noise and a wider bandwidth compared to its predecessor. The high-pass frequency is set to 10 Hz and low-pass frequency is increased to 5.4 kHz.


Small Form-factor and Portability
ActiveThree was designed with lightweight and portability in mind. By carefully selecting novel electronic components, the ActiveThree circuitry was designed with a quarter of the power consumption (both supply voltage, as well as current consumption, are halved) compared to the ActiveTwo. None of these new components compromise the performance of the ActiveThree. This allowed for the use of a smaller and more lightweight battery, decreasing both the size and weight of ActiveThree's AD-box. ActiveThree comes in a form factor of 162 x 149 x 62 mm and a mere 800g.


Software Adjustable Speedmode Switch
Compared to its predecessor, ActiveThree's sampling rate can now be adjusted within ActiView acquisition software. ActiveThree records and transmits all signals on the maximum (fixed) sample rate of 16,384 Hz and a bandwidth of 5.4 kHz. Down-sampling can be performed in ActiView software to a minimum of 256 Hz. ActiView uses a 5th-order CIC decimation filter when down-sampling to prevent aliasing. The bandwidth of down-sampled data is 1/5th of the selected sample rate.