
Update: the original image I had on top appears to actually be an EMU modular. Thanks to Malte Steiner in the comments for catching it. I moved the image below for reference and moved the image of the current owner Walter Holland on top. I also added an image of Don Preston with the Moog system in 1975.
via The Bob Moog Foundation


The modular is currently owned by Walter Holland of lauded Holland Synthesizers, designers of custom aerospace quality audio equipment. Holland and his musical partner Steve Leonard, keyboardist for The Cretones, will be demonstrating the synthesizer throughout the weekend.Holland’s monolithic four-tiered modular includes three prototype modules created by R.A. Moog, Co. in the late 1960s, making it a truly one-of-a-kind system."
Top: "Walter Holland with his Moog Modular synthesizer."
Middle: "Don Preston with the Moog Modular in 1975 at the Provisional Theater."
Bottom: Per the update above, "Patrick Gleeson assists Herbie Hancock in the early 1970s" on an EMU modular.
See the full post including additional pics at the Bob Moog Foundation website here.