BARR & STROUD VARIABLE FILTER TYPE EF-3 Book Soundgas Springathon YouTube demo below

Soundgas Springathon YouTube demo below - 14 springs go head to head

We’ve had this in our studio for a while as I've been enjoying it so much

The pot code dates from 1979 and it is in very clean condition indeed

The tremolo can be subtle and shimmery or full-on throbbing depending on where the depth control is set

but we felt it to be part of the synth's history/identity - as did the US synth tech who worked on it previously)

BARR & STROUD VARIABLE FILTER TYPE EF-3 Book Soundgas Springathon YouTube demo belowOffered for sale is this Barr & Stroud Variable Filter EF 3 in excellent cosmetic condition and good working order (see photos for details). This is an extremely high spec dual filter unit as used by the BBC and various labs around the world: it offers very precise filtering. It requires BNC connectors adaptors for audio use. These units are famed for their high build quality and are designed for use in forensic audio they have also gained a following