BIOPAC® Systems, Inc. Logo

Maximum number of channels for EEG

If you are using a single MP100/MP150 system, the maximum number of EEG amplifiers you can have is 16.  If more channels are required, it is possible to link acquisitions from more than one MP150.  However, the modular design of MP150 systems does not lend itself well to high density EEG recording, so BIOPAC does not strongly recommend this solution.
The Mobita System 32-channel wireless EEG system is a better solution for multi-channel applications.
Unipolar recording:
For unipolar recording you need as many amplifiers as you have sites to record from. For example, for 16 sites you would need 16 EEG amplifiers.  To perform this recording you would need 16 active electrodes, 1 reference (linked via 15 jumper cables to connect all amplifiers), and 1 ground.
Bipolar recording:
For bipolar recording the number of EEG amplifiers will be the same as the number of pairs of electrode sites for which you want to calculate the potential difference. Therefore, if you want to look at all possible pairs, you can calculate the combinations without repetition: n!/(r!(n-r)!) where n is the number of electrode sites and r is 2. For example, for a bipolar recording on 5 sites you would need 5!/(2!3!) = 10 EEG amplifiers. This assumes that you want to look at the potential difference between all possible combinations of electrode sites. This is the maximum number of EEG amplifiers that would be required.
Here is a reference for the number of EEG amplifiers required if you need to look at all electrode pair potential differences:
2 electrodes: 1 amplifier
3 electrodes: 3 amplifiers
4 electrodes: 6 amplifiers
5 electrodes: 10 amplifiers
6 electrodes: 15 amplifiers
Page last modified 30Dec2014

Associated Applications

Spotlight On
Smart Center controller, 2-3 wireless transmitters & AcqKnowledge plus case

Smart Center | Stand-alone BioNomadix Wireless Systems

Smart Center Stand-alone, Portable Wireless Physiology Systems Smart Center Essentials entry-level system includes a Smart Center Device (BN-SMART with USB power cable), 2 or 3 Transmitters (BN-xxx-T with chargers); AcqKnowledge for Smart Center, and a case. Smart Center Enhanced adds a Logger (BN-LOGGER) and Basic Scripting License (ACK100W-BAS) to the Smart Center Device (BN-SMART with powercable), 3 […]

View All
Latest News

Students Get Smart

Science Night at Adams Elementary (Santa Barbara, CA) encourages students to discover, play, explore and learn about the importance of science and engineering in daily life. BIOPAC set up a BioNomadix Wireless Smart Center to allow students to record their hear rate. Electrodes were placed on students and leads were connected to a wireless transmitter that sent data […]

New Citations | Stimulation and Mental Processing

Recent developments regarding electric stimulation and mental processing have lead to interesting developments in psychophysiology and physiological sciences. The following studies look at developments in how we potentially care for and understand solutions to issues with mental health, as well as new ways to monitor electrical stimulus on participants. The ventromedial prefrontal cortex (vmPFC) is […]

Read All
Request a Demonstration
Request a Demonstration