DC 24
DYNAMIC CONTROLLER
Data Sheet-4
All features & specifications subject to change without notice.DOC 107501
Rear Panel
Available Accessories
• SC 1.7 Security Cover
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5098 TEL 425-355-6000 FAX 425-347-7757 WEB www.rane.com
Application Information
Traditionally, a product such as the DC 24 has been referred
to as a “Compressor / Limiter” because the range of the Ratio
control on the Compressor has been wide enough to accommo-
date both gentle compression and harder limiting effects. Not,
however, simultaneously. One had to make a choice between the
two modes of operation. On some models a Gate has been pro-
vided which may or may not be part of the Compressor function.
In the DC 24, all three functions of each channel are inde-
pendent. Gating may occur when low-level signals are present,
compression may occur when the level increases, and “peak-stop”
limiting is available for high-level signals. This provides a three
slope capability which is rather unique in the audio industry.
Additionally, the DC 24 can help out a great deal on the low
end of the amplitude spectrum by serving as a noise gate simul-
taneously. The Compressor may be used to “tighten” vocals and
instrumentals while leaving the Limiter function available for use
as a safety valve.
To accomplish this feat, the DC 24 provides three separate
“Side Chains” in each Channel, each having its own set of front
panel controls. For the Gate / Expander function, input signal
is converted from an audio format to a control signal and ap-
plied to the threshold circuit. If the output of the controller is
below the specified threshold, it is passed along to the Gate /
Expander Ratio control. The Ratio control allows attenuation of
the controller to inhibit the slope of the Expander. After this at-
tenuation, the control signal is delivered to the Channel’s control
summing amplifier where it will meet similar signals generated
by the Compressor control system.
The Compressor controller works remarkably similarly to the
Gate, the exception being the polarity. While the Gate circuit
reduces gain when input level decreases below Threshold, the
Compressor decreases gain when input increases above Thresh-
old. The Compressor also receives the output of the controller,
applies it to its threshold determinator, and passes the signal
to the ratio attenuator if threshold conditions are satisfied. The
output of the Ratio control is applied to the summing amplifier
referenced in the gate section.
Side Chain inserts have been provided on the rear of the unit
to allow the insertion of an equalizer into the control circuits
of the Gate and the Compressor. This will allow the user to
create a frequency-dependent threshold for the Gate and/or the
Compressor. This feature is useful when attempting to control
sibilance in vocals.
The Limiter operates in an entirely different manner than the
preceding sections. The control circuit for the Limiter monitors
the output of the VCA, not the input of the unit. Anytime the
output of the VCA exceeds the Threshold set on the front panel,
Limiting begins to take place. The ratio of the Limiter is set
automatically and is a function of the excess level the system is
attempting to deliver above the preset Threshold. The attack and
release time of the Limiter is a function of the speed at which the
input signal is attempting to drive the output of the unit above
the Threshold level.
The Crossover function of the DC 24 is based on Rane’s
time-proven 4th-order state-variable Linkwitz-Riley design. This
yields a 24 dB per octave slope and an in-phase characteristic.
Since the outputs are in phase with each other, they recombine
properly when the channel summing mode is selected via the
rear panel Separate/Combine switch.
In its band-split mode, the DC 24 allows separate processing
of low frequencies and high frequencies; a mode which makes its
operation all the more transparent. When the Crossover is used
in conjunction with a two-way loudspeaker system, adequate
driver protection may be ensured while providing a very flexible
means of program manipulation.
For a better view of the various operational modes, refer to
“The DC 24 Users Guide”
RaneNote, from the Rane website.
OUTPUTS
CH 2 TRIM
CH 2 HIGH /
COMBINE OUT
CH 2
IN
CROSSOVER
ENGAGE
CLASS 2 EQUIPMENT
CH 1 /
CROSSOVER IN
CH 1 /
LOW OUT
DC 24
+4 dBu
COMBINE
SEPARATE
-10 dBV
TIP=SEND
RING=RETURN
TIP=SEND
RING=RETURN
INPUTS AND OUTPUTS
TIP=#2=POSITIVE
RING=#3=NEGATIVE
SLEEVE=#1=SIGNAL GROUND
CH 1
SIDE CHAIN
CH 2
SIDE CHAIN
MADE IN U.S.A.
RANE CORP.
N108
+4 dBu
-10 dBV
CH 1 TRIM
600mA
POWER
