What are the main differences between ActiveThree and its predecessor, ActiveTwo?

  • ADC type – ActiveThree uses a 24 bit SAR ADC, while ActiveTwo uses a 24 bit Delta-Sigma ADC. This SAR ADC provides a cleaner frequency response without spurious tones that can occur with Delta-Sigma ADCs and may impact ones ability to distinguish signal from noise at certain frequencies in FFR paradigms.
  • Number of channels — ActiveThree has a maximum of 136 biopotential channels plus six auxiliary sensors. ActiveTwo has a maximum of 264 biopotential channels plus four auxiliary sensors.
  • High frequency response – ActiveThree has a low-pass antialiasing filter at 5.4 kHz, while ActiveTwo has a low-pass antialiasing filter at 3.2 kHz.
  • Battery type – ActiveThree uses a single Li-ion battery cell, while ActiveTwo uses a multi-cell Lead-acid battery unit. This new battery type supports the use of modern low voltage components and greater power efficiency.
  • Auxiliary sensors for ActiveThree require no installation of new internal components — all that is needed is already built-in. All you need to do is purchase the sensor and plug it in. The software automatically detects what is plugged in and displays/saves the sensors being used. ActiveTwo requires internal sensor couplers to be installed inside the AD box, and the user needs to select the desired sensors on the Sensors tab.
  • ActiveThree’s CMS/DRL circuitry was redesigned for improved suppression of interference from a wide range of ubiquitous high-frequency interference sources.
  • Weight – ActiveThree’s AD box weights 1.76 lbs with the battery, and ActiveTwo weights 2.4 lbs with the battery.
  • Size – ActiveThree’s AD box measures about 6.4 X 5.9 X 2.4 in with battery, and ActiveTwo’s AD box measures about 4.7 X 5.9 X 7.5 in with battery.