Output Limiters; Link (Stereo Operation); Tone Oscillator / Slate Microphone; Tone Oscillator - Sound Devices 302 User Manual

302 Compact Production Mixer
User Guide and Technical Information
When the output level is set to a level different than
the factory default of Line, the Output Attenuation LED
on the output panel illuminates. This is a quick reminder
that the XLR output is not line-level. See Appendix C
for more information on output attenuation and meter
matching.
Tape Out (Mix Output)
The 302 has an unbalanced, two-channel tape level out-
put on a single locking TA3-type connector. Tape output
program is identical to XLR output program, although
they are isolated from each other. The 302 tape output
O L
UTPUT IMITERS
In addition to the limiters on each input channel, the
302 has a software-controlled limiter for the output
buses. Output limiters are used to prevent overload of
recorders, cameras, and wireless transmitters connected
to the 302. The output limiter on the 302 is a optoisola-
tor-based peak limiting circuit. Its threshold of opera-
tion is set in the User Menu. The output limiter can be
set in one of two positions, Link or LIM.

Link (Stereo Operation)

When set in the link position, the output limiter acts
identically on each output bus. If one output makes the
T O
ONE SCILLATOR
A single 3-position switch controls both the tone oscil-
lator and the slate microphone. The tone/slate switch
is located in the upper right corner, protected from
inadvertent engagement by the end panel. When the
tone oscillator or slate microphone is engaged program
is interrupted to the master bus.

Tone Oscillator

Tone is used to set gain structure between the 302 and
the next device in the signal path. The tone oscillator
uses the locking position of the switch.
From the factory, the tone oscillator is set to output a 1
kHz tone at 0 dBu to the outputs (when the outputs are
set to Line level). In the Setup Menu, the tone frequency
and output level can be adjusted and tone can be de-
feated.
When engaged, the 302 tone oscillator attenuates the
headphone output by 20 dB to save the operator's ears.
This feature can be defeated in the Setup Menu.
/ S M
LATE ICROPHONE
is typically used to interface the 302 mixer with con-
sumer-type inputs such as MiniDiscs, DATs, and compact
cassette recorders. The tape output is also used to feed
wireless transmitters when the masters are connected to
cameras or recorders. The tape output is isolated from
the main output – devices connected to the tape out
have no effect on the master outputs.
The Tape Out is also used when linking the 302 to an-
other 302 mixer or Sound Devices 442 Field Mixer. Using
the XL-1 cable supplied with the 442, connect the 302
Mix Output to the 442 Mix In connection. All three of
the 302 inputs appear at the 442 master outputs.
limiter engage, the other bus will follow suit. This is
very useful when using the 302 in stereo—limiter opera-
tion will not affect the stereo image.

LIM (Dual-Mono)

When using each output bus separately the output
limiter should be set to the ON position. This position
engages each output limiter separately. They will act on
each respective output bus independently of the other.
While all dynamics processing "distorts" the audio signal, overloading a
circuit is usually far more objectionable. For most applications the limit-
ers are a signifi cant benefi t and should be enabled.
Pressing the battery check button when the tone oscil-
lator is active sets the left output to cycle between 0
and -20 dB. This is helpful to verify proper left and right
channel connection. Turning off the tone oscillator or
pressing the battery check button again stops the out-
put cycling.
When adjusting the output attenuation in setup mode, activating the
tone oscillator will output a full-scale tone to aid in gain structure setup.

Slate Microphone

The slate microphone is used to audibly notate scenes at
the mixer location. Its audio performance is not suitable
for critical recording applications; it should only be used
for documenting scenes to tape. The slate mic uses the
momentary switch position.
In the Setup Menu, a one second 400 Hz tone can be set
to precede the slate microphone. The slate microphone
signal is sent to all outputs. In the Setup Menu, the slate
microphone can be disabled to prevent unintended ac-
tivation. Also, the switch assignments of slate and tone
can be reversed for convenience.
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