Osiris PHILter Osiris PHILter Model# 72-79, 2026 - Mahogany 2026 - Mahogany, Abalone, Mother of Pearl

Outboard version of the filters in Phil Lesh's legendary Alembic Bass known as "Osiris" aka "Mission Control". The PHILter is reverse engineered from the original filters built by George Mundy for Phil around 1972 or 1973. Phil played Osiris from 1974-1979, and these filters can be heard on countless incredible live recordings of that era, as well as multiple studio albums. These filters are also very similar to the filters in "Big Brown" which Phil played mostly in 1972 and 1973. Our PHILter is handwired in the USA and features a furniture grade Mahogany cap with inlaid Mother of Pearl and Abalone star to match the stunning beauty of Osiris. The PHILter sounds marveLESH on bass, and fabuLESH on guitar as well. Gruhn Guitars is very proud to offer this unique and brilliant tool - if you are in Nashville, come by and try it out in person. To see a video demonstration, copy and paste this link into your browser: