Series, 160s, 160sl – dbx 160SL User Manual

Page 15

160S

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series

160S

controls

160S

notes

160S

Operations

160S

Operations

Inspection

Operating

Connection

Installation

Technical

Introduction

to your system

considerations

contents

concept

diagram

applications

support and factory service

160S

Specifications

160S

Manual

Design

Block

Controls

Advanced

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By pass Switch and LED

: This switch activates a hard-wire relay bypass system, which allows the audio

signal to pass through the compressor directly from input to output, even when the 160SL is turned off.
That is to say that the XLR Pin 2 at the input connector is directly connected to the XLR Pin 2 at the
output connector, and the XLR Pin 3 at the input connector is directly connected to the XLR Pin 3 at the
output connector. When the 160SL is in bypass mode the LED directly above the Bypass switch is lit.

Note

Bypass mode can be very useful for applications such as A-B comparisons, comparing processed signal with unprocessed signal.

Ou tput Gain Control

: This control adjusts the amount of gain in the 160SL’s output amplifier stage. The

signal can be attenuated or boosted by a full 20dB relative to a “0” center setting, representing unity
gain. This control is independent of the threshold or compression ratio settings. Because 20dB of gain
can be added at the 160SL output, it is possible to cause clipping even when the input level is within
the specified range. When the compression ratio is set at a low number, extreme clockwise rotation of
the Output Gain control could cause the 160SL output stage to clip audio program peaks. Therefore,
for normal operation we suggest setting the Output Gain control to “0dB” (12 o’clock position) as a
starting position. Where the circuit fed by the 160SL has a high input sensitivity, lowering the output
gain setting can avoid the need for an attenuation pad in subsequent equipment.

Pe ak LED

: This LED is located to the left of the VU Meter. It is set to light when the signal level at the

output level reaches +27dBu. This represents a headroom measurement of approximately 3dB before
hard clipping will occur, due to the maximum output level of the 160SL (+30dBu).

VU Meter

: The custom designed analog meter is made to serve 3 different functions: first, it measures

the amount of input signal presented at the input connector corresponding to its channel. Second,
it measures the output signal at the output connector, after all processing has taken place, including
output gain. Third, it shows the amount of gain reduction being induced into the input signal, measured
after both the compressor settings and limiter settings. Note that the meter, in input and output mode,
measures accurately from -30dB to +6dB. There is 17dB between the upper end of the meter, and the
setting at which the Peak LED lights. Be aware that while the occasional “pegging” of the meter will
likely not effect the internal dynamics of the 160SL, due to its unheard-of dynamic range (123dB), it is
possible that the output signal from the 160SL could cause distortion in subsequent gear, if the output
signal stays above the +6dB marking on the meter for an extended period of time. The dynamic range
of the 160SL is meant to provide an

extremely low noise floor at optimum operating level (“0”dB, which

is +4dBu), and to provide protection for the occasional excursion above the nominal operating range. It
was not meant to provide continuous operation in the 17dB of “no-man’s-land” between the upper end
of the analog meter and the setting of the Peak LED.

In Gain Reduction mode, the meter moves to indicate the amount of gain reduction, in dB, the

compressor/limiter settings are imposing on the output signal. When first activated, the meter’s needle
will jump to the “0” mark of the lower scale on the meter (only if there is no gain reduction happening),
indicating “zero gain reduction”, and will move to the left indicating the amount of gain reduction in the
signal level, up to a maximum of 30dB of gain reduction.

160SL

lue

series

160SL

controls

160SL

notes

160SL

Operations

160SL

Operations

Inspection

Operating

Connection

Installation

Technical

Introduction

to your system

considerations

contents

concept

diagram

applications

support and factory service

160SL

Specifications

160SL

Manual

Design

Block

Controls

Advanced

Warranty

lue

series