# Empty room SSP vs. Maxwell filtering

**URL:** <https://mne.discourse.group/t/empty-room-ssp-vs-maxwell-filtering/2026>\
**Category:** Mailing List Archive (read-only)\
**Tags:** list-archive\
**Created:** [December 18, 2019, 6:52pm UTC](https://mne.discourse.group/t/empty-room-ssp-vs-maxwell-filtering/2026 "2019-12-18T18:52:12Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\
**Post date:** [December 18, 2019, 6:52pm UTC](https://mne.discourse.group/t/empty-room-ssp-vs-maxwell-filtering/2026/1 "2019-12-18T18:52:12Z")

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Dear Alex and Denis,  
Could you tell us what is the importance of removing the empty room noise  
component using SSP? Wouldn't the maxwell filtering remove the empty room  
noise component by default?

Thanks in advance,  
Harish

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**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\
**Post date:** [December 18, 2019, 10:00pm UTC](https://mne.discourse.group/t/empty-room-ssp-vs-maxwell-filtering/2026/2 "2019-12-18T22:00:55Z")

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Well I guess you're asking why one should process the empty room recording  
like one processes the data?  
You simply want to make sure the rank of the data is the same and the only  
difference is in the content of the signal, not the processing applied.

Does that make sense?  
Denis