Buchla 200e series, User Manual

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Model 230e Triple Envelope Tracker
230101013
This module is in two sections. The top section tracks the dynamics of applied
signals, and the bottom section amplifies small signals from an external
instrument or microphone. The two sections are normally connected internally
(“normalled”), but if desired, they can be used independently.
First we’ll describe the workings of the mike preamp, of which there are three.
The input connectors accept either Canon XLR’s or standard ¼ inch phone
plugs. Three gain ranges are provided, indicated by LED’s, and selected by
quick presses of the “gain sets”. The highest (40db) range is usually required
for microphones, while instruments will usually thrive with lower gain settings.
Phantom power is available for microphones that require it – switch it on or
off by pressing any gain switch and hold for about a second. Phantom power
indicated by the green LED is applied simultaneously to all XLR inputs, but
never to the ¼” inputs on these jacks.
Individual microphone outputs are provided, as well as a mixed output. An
expansion input allows one to use additional modules to expand the inputs.
Envelope Follower: Now for the envelope tracker. The three envelope
trackers are normally connected to the three mic preamps. These internal
“normalled” connections are indicated by circled “N”’s on the panel. If desired
to use an envelope tracker independently, simply patch the its input jack to
whatever source you’d like and “normalled” connection will disconnect.
With a signal applied, adjust the “sens” to turn on the orange LED’s; if the gain
is such that a c.v. output exceeds 10 volts, a red “overload” light will warn you.
The decay times of the envelope trackers are variable from .1 to 10 seconds.
Pulse outputs: Pulse outputs have two levels in the 200e system. The
sustain level is 5 volts, and transients are short 10 volt pulses. Sustained
pulses are outputted when the envelope exceeds 5 volts, causing the “action”
LED to glow dimly.
The condition for a transient pulse is determined by the state of the “trans”
LED. If it is off, transients are generated whenever the sustain threshold is
exceeded. If switched on, transient pulses are generated only when a
significant c.v. increase occurs, independently of the level. Such pulses cause
the “action” LED to flash brightly. Transient signals can thus generate pulses
in the presence of background sounds, a particularly useful feature when
extracting rhythmic information, as from a drum.
Remote Enable: To connect or disconnect this module from the central library
function, push the remote switch. The lighted LED signifies a connection.