During March 2025, Sohn focused on improving digital signal processing reliability in the simonsobs/sotodlib repository by addressing a critical filter design issue. He replaced the existing Butter4 bandwidth filter with a sine-squared filter for both band-pass and low-pass operations, using Python to implement the new approach. This change enhanced the accuracy and robustness of the filtering pipeline, reducing discrepancies in edge cases and supporting more consistent data processing. Sohn also updated documentation and usage examples to reflect the new filter, making it easier for developers to understand and apply the changes. His work demonstrated depth in filter design and signal processing.