2-9
RCL SOUTPUT
LCRS
OFF
CSCS
NOISE SEQUENCE
AUTO
MANUAL
PINK NOISE
Figure 2.9 Pink-noise calibrate functions
Output Level Adjustments
Output potentiometers are provided so that the decoder output level can be
matched to the monitor system. Typically, the SDU4 output level is set using
the internal pink noise source.
The front panel master level control is set to the “∇” mark (2 o’clock). Then the
SDU4 output trims, (or alternatively, the level controls on the power amplifiers)
are set so that the sound pressure level in the primary listening area is adjusted
to the recommended level (usually 85dBc) with one channel at a time being
driven with wide-band pink noise.
In cases where the SDU4 outputs are routed though a switching system and the
outputs from other devices are connected to the power amplifiers, set the SDU4
outputs to an established house reference level (+4dBr, for instance) and make
the final monitor level adjustments at the power amplifiers.
Master Level Control
The SDU4 contains a four channel master level control that allows the overall
listening level to be adjusted up or downward without upsetting the individual
channel balance. The “∇” position should be considered the normal operating
level.
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