Key additions:

RVV SIMD support for RISC-V devices.

Elliptic IIR filter design and zero-phase IIR filtering via filtfilt.

Audio reading/writing completely reworked and now supports WAV, W64, RF64/BW64, AIFF, FLAC, CAF, ALAC, MP3, and raw formats.

New high-level Audio module for multichannel processing.

There are also performance improvements since KFR6 for DFT (up to 40% on ARM) and matrix transpose (up to 30%).

See benchmarks done by LIGO-Virgo-KAGRA collaborations https://news.ycombinator.com/item?id=45955957