I recently ran across a new open-source (or is it source-available?) EEG board that looks interesting: the Cerelog ESP-EEG.

At its heart is the Texas Instruments ADS1299 (24-bit, 8-channel) analog-digital converter, the same chip the OpenBCI Cyton uses.

So what's different or better about the Cerelog? From my perusal of the materials, it seems that the selling point is cleaner signal due to true closed-loop active bias, at a price point close to the price of the OpenBCI when it launched (less than half the price of the Cyton now).

Software support includes a fork of the OpenBCI GUI (via Lab Streaming Layer) and Brainflow.

The project is by former SpaceX hardware engineer Simon Hakimian.

Git repository with firmware and schematic here:

⇒ https://github.com/Cerelog-ESP-EEG/ESP-EEG

Product page:

⇒ https://www.cerelog.com/eeg_researchers.html

Usage guide:

⇒ https://www.cerelog.com/eeg_researchers_guide.html

Socials:

⇒ https://x.com/CerelogOfficial

Announcement post on Reddit r/BCI:

⇒ https://old.reddit.com/r/BCI/comments/1polj4b/i_designed_an_open_source_8channel_eeg_board/

More info about where this is going:

⇒ https://www.cerelog.com/investor_info.html

Cerelog also has a tCDS board available for pre-order:

⇒ https://www.cerelog.com/tdcs_researchers.html

YouTube video:

⇒ https://www.youtube.com/watch?v=6XKdIbguI00

Caveats:

• It has hardware support for Bluetooth/Wifi, but the firmware isn't ready yet, so for the time being it can only be used with USB, which means it isn't electrically isolated, which means absolutely don't ever use it with a desktop computer or a laptop that is charging.

• Some of the promo materials sound like they could have been hallucinated by an LLM; but then, investor-speak has never sounded human to me.

• Though the schematics and firmware are open source (MIT Licence, and CC-BY-NC-SA 4.0), the PCB layout files are specifically not available, and the firmware/schematics only allow non-commercial use.

• In the guide it says the firmware is not available unless you email; elsewhere it says it's open source under MIT licence. And in some places it says the hardware is CC-BY-NC-SA 4.0, and elsewhere it says it's merely CC-BY-SA 4.0. I'm confused!

Questions:

• This is so similar to the OpenBCI, why not just fork the OpenBCI hardware and software, and add true closed-loop active bias?