FOR REVIEWS of my 'Sound Foundations' 'Audio Engineering Reference Guide' and 'Optimal Reaper', use this link: https://www.amazon.com/gp/search/ref=sr_gnr_fkmr1?rh=i%3Aaps%2Ck%3AMarkus+Heinrich+Rehbach&keywords=Markus+Heinrich+Rehbach&ie=UTF8&qid=1542635462