EWI-fied re.corder 4 : closed system, final version

Newer version : Rotary encoder, portamento level were added.

Production Process Slides

#### UPDATE 12/24/2022 ####

I updated my EWI-fied re.corder 4 into 4.1 : removed the one way air flow valve as it made the instrument heavy. improved the bite sensor for vibrato.