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this auction
This one is being auctioned off by Ezra Buchla, Don Buchla's son.
"This is a Buchla model 207 mixer and preamplifier from the 200 series, made sometime in the early 1970's. It is quite rare and consists of all original components.
The mixer section includes 6 input channels, 4 of which have manual control over location, and two of which have voltage control of location. This section also includes a third, independently switchable mono output bus.
The pre-amplifier section has a single 1/4" input, three switchable gain/impedance settings and a potentiometer for finer gain control."