Add SOUND and SSP-SIR algorithms about mne-python

[welcome]

Hello! 👋 Thanks for opening your first issue here! ❤️ We will try to get back to you soon. 🚴

[larsoner]

From a very brief look it seems like SSP-SIR is a bit like proj="reconstruct" in #8033 / this tutorial but someone would have to dig into the details to see

For SOUND I'm not too familiar with how widely used it is. See also discussions of other potential algorithms like #7170 (comment) where we suggest possible inclusion in python-meegkit or mne-sandbox to start until we see how widely used they are

[matteo-d-m]

Thanks for your response.

• proj="reconstruct" might indeed be some implementation of SSP-SIR, but we are trying it on some real data to check
• I believe that SOUND would be a valuable addition to MNE, but I also understand your concern. I'll just do the work and propose it to either MEEGKit or MNE-Incubator when it's done!