“The vintage 1976 Oberheim VCF-200 Voltage Controlled Filter with Envelope Follower and Sample/Hold. Monster cool device — Frank Zappa actually owned a 1976 Oberheim VCF-200 and used it for the insanely funky sample-and-hold percolation effect heard on “Ship Ahoy” from Shut Up ‘N Play Yer Guitar Some More.”
“This amazing machine offers two modes: ENV (Envelope Filter) and S/H (Sample/Hold). It is very similar to the 1975 Maestro FSH-1 Filter Sample/Hold which Oberheim actually built for Maestro. Some say it sounds better than the Maestro FSH-1 because of better op-amps and transistors.”
More information here:
