Synchronized Sine Sweep
https://github.com/SiggiGue/syncsweptsine
https://www.conforg.fr/euronoise2015/proceedings/data/articles/000420.pdf
OTFFT: High Speed FFT library
http://wwwa.pikara.ne.jp/okojisan/otfft-en/optimization1.html
Faster Log10 and Pow
https://openaudio.blogspot.com/2017/02/faster-log10-and-pow.html