The Meditation Reserach Institute Switzerland (MRIS) retreated for the time being from EEG devices from

BITalino:

from www.OpenBCI.com

and from PiEEG:

And the reason for this can be found in our journal under the tag «EEG»:

https://petergamma.org/category/eeg-devices/

And we suggest to choose for open source developers at the level of the Swiss Federal Institute of Technology of Zurich to choose this architecture:

Developers wanted to build a 4 channel EEG device from a ADS1115 analog to digital converter & 4 individual TGAM EEG modules

together with this architecture:

How to build a physiological multi-sensor device based on InfluxDB?

Instead.