Rane G4 User manual
G4
GATE
msms
n:1
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Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
612-12 -6 -3 -1 31-24
dBu
612-12 -6 -3 -1 31-24 612-12 -6 -3 -1 31-24 612-12 -6 -3 -1 31-24
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G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
12
DEPTH
34
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION
To reduce the risk of electrical shock, do not open the unit. No user
serviceable parts inside. Refer servicing to qualied service personnel.
e symbols shown below are internationally accepted symbols
that warn of potential hazards with electrical products.
is symbol indicates that a dangerous voltage
constituting a risk of electric shock is present
within this unit.
is symbol indicates that there are important
operating and maintenance instructions in the
literature accompanying this unit.
WARNING
IMPORTANT SAFETY INSTRUCTIONS
1. Read these instructions.
2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with a dry cloth.
7. Do not block any ventilation openings. Install in accordance with manufacturer’s instructions.
8. Do not install near any heat sources such as radiators, registers, stoves, or other apparatus (including ampliers) that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than the other. A
grounding-type plug has two blades and a third grounding prong. e wide blade or third prong is provided for your safety. If the provided plug
does not t into your outlet, consult an electrician for replacement of the obsolete outlet.
10. Protect the power cord and plug from being walked on or pinched particularly at plugs, convenience receptacles, and the point where it exits from
the apparatus.
11. Only use attachments and accessories specied by Rane.
12. Use only with the cart, stand, tripod, bracket, or table specied by the manufacturer, or sold with the apparatus. When a cart is used, use caution
when moving the cart/apparatus combination to avoid injury from tip-over.
13. Unplug this apparatus during lightning storms or when unused for long periods of time.
14. Refer all servicing to qualied service personnel. Servicing is required when the apparatus has been damaged in any way, such as power supply
cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does
not operate normally, or has been dropped.
15. e plug on the power cord is the AC mains disconnect device and must remain readily operable. To completely disconnect this apparatus from
the AC mains, disconnect the power supply cord plug from the AC receptacle.
16. is apparatus shall be connected to a mains socket outlet with a protective earthing connection.
17. When permanently connected, an all-pole mains switch with a contact separation of at least 3 mm in each pole shall be incorporated in the
electrical installation of the building.
18. If rackmounting, provide adequate ventilation. Equipment may be located above or below this apparatus, but some equipment (like large power
ampliers) may cause an unacceptable amount of hum or may generate too much heat and degrade the performance of this apparatus.
19. is apparatus may be installed in an industry standard equipment rack. Use screws through all mounting holes to provide the best support.
WARNING: To reduce the risk of re or electric shock, do not expose this apparatus to rain or moisture. Apparatus shall not be exposed to dripping
or splashing and no objects lled with liquids, such as vases, shall be placed on the apparatus.
NOTE: is equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules.
ese limits are designed to provide reasonable protection against harmful interference in a residential installation. is equipment generates, uses
and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment o and on, the user is encouraged to try to correct
the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit dierent from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
CAUTION: Changes or modications not expressly approved by Rane Corporation could void the user's authority to operate the equipment.
is Class B digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.
WARNING: is product may contain chemicals known to the State of California to cause cancer, or birth defects or other reproductive harm.
Manual-1
G4
QUAD GATE / DUCKER / EXPANDER
OPERATORS MANUAL
WEAR PARTS: is product contains no wear parts.
Quick Start
If you read just one page of a manual this year, it should be this one.
If you are not familiar with the operation of Gates, Duckers and Expanders, see the Operation section on page Manual-4 for a
good tutorial. For those of you familiar with their operation, this quick start should help you get up and going fast.
Basic Gating: e G4 allows complete Gate envelope control: reshold, Attack, Release and Hold. Side-chain metering accurately
and consistently indicates where the key signal is relative to the reshold (dBr).
A good starting procedure is as follows:
1. Select the GATE mode and set for BYPASS.
2. Select side-chain key source for INTernal or EXTernal as required.
3. Set ATTACK to 0 ms, RELEASE for 250 ms, HOLD for 125 ms and DEPTH for 20 dB.
4. Select side-chain LISTEN.
5. Listen to the key signal and adjust the LOW-CUT and HIGH-CUT lters to respond only to frequencies of interest.
6. Watch the SIDE-CHAIN meter and adjust the THRESHOLD until the yellow TH indicator lights at the desired level.
7. Set the side-chain from LISTEN to NORMAL and the BYPASS to ACTIVE.
Basic ducking: As with the gate, the G4 provides complete Ducking envelope control. Figure 5 on page Manual-6 graphs the re-
sponse. A good starting procedure is as follows:
1. Select the DUCK mode and set for BYPASS
2. Select side-chain key source for EXTernal. Ducking always uses an external side-chain key input.
3. Set ATTACK to 0 ms, RELEASE for 1 second, HOLD for 3 seconds and DEPTH for 20 dB.
4. Select side-chain LISTEN.
5. Listen to the key signal and adjust the LOW-CUT and HIGH-CUT lters to respond only to frequencies of interest.
6. Watch the SIDE-CHAIN meter and adjust the THRESHOLD until the yellow TH indicator lights at the desired level.
7. Set the side-chain from LISTEN to NORMAL and the BYPASS to ACTIVE.
Basic Expander: Expander operation is similar to that of the Gate, with two important control dierences:
• e HOLD control is not active in EXPand mode.
• e RATIO control is used in place of the DEPTH control.
1. Select the EXPand mode and set for BYPASS.
2. Select side-chain key source for INTernal or EXTernal as required.
3. Set ATTACK to 100 ms, RELEASE for 500 ms, RATIO for 3:1.
4. Select side-chain LISTEN.
5. Listen to the key signal and adjust the LOW-CUT and HIGH-CUT lters to respond only to frequencies of interest.
6. Watch the SIDE-CHAIN meter and adjust the THRESHOLD until the yellow TH indicator lights at the desired level.
7. Set the side-chain from LISTEN to NORMAL and the BYPASS to ACTIVE.
Contents
Front Panel Controls...........................................................2
Operation ............................................................................4
Side-chain Detector .........................................................4
Gate Mode.........................................................................4
Expand Mode....................................................................5
Duck Mode........................................................................6
Kick Drum Attack Example ................................................6
msms
n:1
dB
Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
612-12 -6 -3 -1 31-24
dBu
612-12 -6 -3 -1 31-24 612-12 -6 -3 -1 31-24 612-12 -6 -3 -1 31-24
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
26
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
26
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
26
10
40
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80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
26
10
40
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80 5k
315
80
1.25k
20 20k
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6.3k
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G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
12
DEPTH
34
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
Active / Bypass switch
e Active / Bypass switch bypasses or activates dynamics
processing for each channel. Side-chain metering and Listen
continue to operate in Bypass. Bypass switches remain indepen-
dent in Link mode.
Gate / Duck / Expand mode switch
e G4 has three modes of operation: Gate, Ducker or down-
ward Expander. See the Operation section on page Manual-4
for operation details of each mode.
Threshold
In Gate mode, THRESHOLD sets the key level below which
the Gate is closed.
In Expand mode, THRESHOLD sets the key level below
which downward expansion takes place.
In Duck mode, THRESHOLD sets the key level above
which the signal is ducked.
Attack
In Gate mode, ATTACK determines how quickly the Gate
opens when the key signal goes above the set threshold.
In Expand mode, ATTACK determines the rate of gain in-
crease as the key signal moves toward or above the set threshold.
In Duck mode, ATTACK determines how quickly the
signal is ducked as the key signal goes above threshold.
Front Panel Controls
Meters
e eleven-segment SIDE-CHAIN signal meter indicates
level relative to the reshold (dBr), allowing easy and intuitive
adjustment of the Gate threshold. e reshold indicator TH
is lit whenever the ltered side-chain signal is at or above the
set threshold. e signal peak value is held briey to assist in
setting a proper threshold.
Meter ballistics follow the response of the side-chain detec-
tor. Gate and Duck modes use peak detection with instanta-
neous attack and 25 ms decay. Expand mode uses rms detection
with an averaging time constant of 50 ms.
Gate status is shown using a seven-segment gain reduction/
gate meter. is meter is eectively an expanded version of the
simple “stop light” meter found on many gates. e inclusion
of gain reduction metering allows the user to view the transi-
tion progress of the Gate and Ducker as well as the current gain
reduction when in Expand mode. e CLOSED LED is not ac-
tive in Expand mode. e response of the gain reduction meter
accurately follows the Attack/Hold/Release envelope.
With this combined metering system it is possible to see at a
glance where the signal level is in relation to the threshold, and
the amount of gain reduction being applied.
Stereo Link
Channels 1 and 2 may be Linked for stereo operation, as may
channels 3 and 4. Channels 1 and 3 act as the Master when
Linked, with channels 2 and 4 operating as Slaves to their
respective Masters. When Linked, only the Master’s rotary
controls and mode select switch are active. e Master controls
the gain reduction of both channels.
Gate and Duck modes use look-ahead peak detection and
the Master uses the larger of the two processed signals. In
downward Expand mode, rms detection is used and the master
uses the rms sum of the ltered side-chain signals.
Side-chain bypass, Internal/External and Listen switches
remain independent when channels are Linked. To trigger from
only one key input, set the key source (INT/EXT) of the signal
you wish to ignore to EXTernal and leave the rear panel side-
chain input disconnected.
Manual-2
612-12-6-3-131-24 TH
CLOSED OPEN
SIDE-CHAIN dBr
OL
MASTER SLAVE
12
LINK
MASTER SLAVE
34
LINK
BYPASSACTIVE
DUCK EXPGATE
dBu
-60
-20 -10-30
-40
-5010
20
0
THRESHOLD
ms
250
50
25 100
0
ATTACK
Release
In Gate mode, the RELEASE setting determines how quickly
the Gate closes (gain decrease) as the key signal drops below
threshold.
In Expand mode, the RELEASE setting determines how
quickly the signal is turned down as the key signal moves below
threshold.
In Duck mode, the RELEASE setting determines how
quickly the signal is ramped up when the key signal drops
below threshold.
Hold
In Gate mode, the HOLD time determines how long the Gate
remains open after the key signal drops below threshold.
In Duck mode, the HOLD time determines how long the
signal remains ducked when the key input drops below thresh-
old.
e HOLD time is reasserted whenever the peak signal
moves above the Gate or Duck threshold.
e HOLD control has no eect in Expand mode.
Depth / Ratio
In Gate mode, the DEPTH control determines how many dB
the signal is attenuated when the key input is at or below thresh-
old. e RATIO control has no eect in Gate mode.
In Duck mode, the DEPTH control determines how many
dB the signal is attenuated (ducked) when the key input is at or
above threshold. e RATIO control has no eect in Duck mode.
In Expand mode, the RATIO control indicates the ratio
of output change to input change when the key signal is at or
below threshold. For example, with a ratio of 4:1, the output
level decreases 4 dB for every 1 dB the key signal moves below
threshold. e DEPTH control has no eect in Expand mode.
Side-Chain Key Sources: Internal / External
e INTernal / EXTernal switch determines the source of the
side-chain key signal.
When set to INT, the channel input is the source. When
set to EXT, the side-chain input jack is the source. Side-chain
source switches remain independent in Link mode.
A wiring diagram to make your own insert cable is below.
Side-Chain: Normal / Listen
e NORMAL / LISTEN switch allows the user to listen to
the ltered side-chain key signal. When set to LISTEN, the
ltered side-chain key signal is routed to the output. Listening
to the ltered key signal assists in adjusting the side-chain lter.
When set to NORMAL , the main processed audio signal is
routed to the output jack. Side-chain Listen switches remain
independent in Link mode.
Side-Chain: Low-Cut and High Cut
e side-chain, 12 dB/octave Butterworth LOW-CUT and
HIGH-CUT lters are used to limit the detector’s response
to a particular range of frequencies, thereby minimizing false
triggering.
ese lters are only applied to the side-chain. ey do not
aect the main output (unless you accidentally leave the LIS-
TEN switch engaged).
Side-chain ltering is advantageous in virtually all dynam-
ics control applications. For example:
• Adjust the HIGH-CUT lter to tune out the mic bleed from
the snare drum or cymbals when gating a kick drum or tom
mic. Similarly, adjust the LOW-CUT lter to tune out the
kick drum when gating a snare mic.
• Adjust the LOW-CUT lter to eliminate background noise
(a low frequency air conditioner, for example) when using a
speech microphone to duck music. e ltered signal is less
likely to false trigger, while the detector remains sensitive to
voice signals.
Manual-3
ms
2 Sec
250
125 500
25
RELEASE
Sec
3
.5
.252
0
HOLD
n:1
dB
8
4
26
10
40
60 20
80
RATIODEPTH
EXTINTLISTENNORMAL
SIDE-CHAIN
Hz Hz
5k
315
80
1.25k
20 20k
2k
630
6.3k
200
LOW-CUTHIGH-CUT
1-CONDUCTOR SHIELDED CABLE
1-CONDUCTOR SHIELDED CABLE
T = SEND
R = RETURN
S = SHIELD
++
SEND
RETURN
++
SHIELD SHIELD
SHIELD
Send/Return Cable Wiring (Insert Cable)
Manual-4
Operation
e G4 has 3 modes: Gate, Ducker or downward Expander.
Side-chain Detector
e side-chain detector compares a reference signal, commonly
referred to as the key signal, to the reshold in order to deter-
mine the response of the Gate/Ducker/Expander. is reference
signal may be a version of the main input (Internal side-chain)
or another signal altogether (using the External side-chain
inputs).
Two types of detection are used in the G4:
• Peak detection is used in Gate and Duck modes to accurately
capture and reproduce transients.
• True rms detection with a xed 35 ms averaging time con-
stant is used in Expand mode.
e look ahead detector works as follows: the main signal is
delayed, while the side-chain signal is not delayed. is delay is
extremely short (a few millionths of a second) and can’t be heard.
e G4 examines the signal in advance and determine the ap-
propriate response before an event (see Figures 2 and 3). is
action allows the Gate and Ducker to turn on before a transient
occurs. Pre-ramping the signal allows the main signal to be
gated-on as the signal reaches the threshold.
Look ahead pre-ramping serves two purposes:
• Leading edge wave shape is preserved above 1 kHz (see
Figure 2).
• It is possible to tighten up the sound of frequencies below
1 kHz without the annoying click resulting from deep gate
depth, high threshold and instantaneous attack settings (see
Figure 3).
Gate Mode
A Gate operates by turning a signal down a xed number of
dB (known as depth) when the key signal drops below a set
threshold.
Figure 1 shows the waveform and envelope of a gated signal.
e leading edge of the envelope is the attack time (0 to 250
ms). e hold time (0 to 3 seconds) determines how long the
gate remains open after the signal goes below the set threshold.
e release rate (25 ms to 2 seconds) determines how rapidly
the Gate closes after the hold time has expired.
e attack setting is equal to 3 time constants, or the time
it takes to reach 95% of the nal value. Because the attack is a
time constant, it takes the same period of time to reach 95 %
of nal value regardless of the Gate depth. is means the Gate
will open in the same period of time from a depth of 80 dB or
6 dB.
e minimum hold time is 25 ms and is based on two
parameters:
• e peak detector uses instantaneous attack and a xed
25 ms hold. is prevents cycle-to-cycle “chatter” at low
frequencies.
• e hold time after detection is adjustable from 0 ms to 3
seconds, giving a minimum hold time of 25 ms and a maxi-
mum hold time of 3.025 seconds.
e release rate is in dB/sec. e front panel setting refers
to the length of time it takes to ramp 10 dB. If the release rate is
set to 250 ms, then it takes: 250 ms to ramp 10 dB, 125 ms to
ramp 5 dB and 2 seconds to ramp 80 dB.
Gating Uses
1. To reduce microphone bleed, handling noise, electrical hum
or incidental back ground noise. Microphones continue to
pick up extraneous noise even when the intended signal is
not present. A Gate eectively closes the microphone in the
absence of the expected signal. Side-chain lters further help
identify intended versus extraneous content by limiting the
frequency response to the frequencies of interest.
Example uses
• Clean up bleed between drum microphones
• Automatically gate speech microphones on/o
• Silence noisy guitar amps between songs.
2. To modify the sound of an instrument. To soften the sound,
use a longer attack, lower threshold and/or reduced depth. To
tighten up the sound, use a shorter attack, higher threshold
and/or increased depth.
Example uses
• Fast attack settings tighten the sound of a drum or percus-
sion instrument.
• Short hold and fast release times give that ultra-cool 80’s Phil
Collins drum sound.
3. To synchronize two sounds. Use the external side-chain
inputs to key one input based on an a secondary input.
Example uses
• Attach a piezo transducer to a drum and use it as an external
side-chain input to accurately gate the drum mic on and o.
Figure 1: Gate Envelope
Manual-5
Figure 2: Look ahead pre- ramping (3 kHz signal)
In the above waveform, the side-chain Gate threshold equals
the peak sine wave value (rst vertical marker). e main input
signal (yellow trace) is delayed a few microseconds. At 3 kHz,
the exponential look-ahead ramp guarantees the rst cycle is
fully gated on as it reaches the threshold level (second vertical
marker). e look ahead and analog converter delays give a total
propagation delay though the G4 of 1.62 ms, an imperceptible
amount.
Expand Mode
e basic objective of expansion is the same as gating: expand
the dynamic range of a signal by reducing the noise oor.
However, an expander provides a more subtle response than a
gate in applications requiring smooth, natural decay. It works by
controlling the ratio of output change to input change, in eect
dynamically modifying gain below a set threshold. For example,
if the ratio is set to 4:1 then the output decreases 4 dB for every
1 dB of decrease in input level (See gure 4).
Compared to gating, expansion typically uses a slower attack
time and longer release time.
Example uses
• Enhance the long, gradual decay of a piano or guitar.
• Use an expander on a quiet vocalist to reduce stage noise
between passages.
Figure 3: Look ahead pre-ramping (500 Hz signal)
At 500 Hz the exponential pre-ramp ensures that the rst cycle
is properly gated on. Look ahead pre-ramping produces a more
natural leading edge to the wave form, tightening up the sound
without the harsh click that occurs with an instantaneous rise
time.
Figure 4: Gate vs. Expander
e above graph shows the dierence between Gate and
Expander operation. e solid red trace shows the side-chain
input.
Gate: e green long-dash trace shows the operation of a
Gate. e Gate attenuates the signal by a xed number of dB
when the signal is below threshold. e response is adjustable
over a wide range using Attack, Release and Hold controls. It
is possible to achieve natural decay with string instruments by
setting the release for slow ramp down. Fast attack, quick release
and deep depth settings can be used to change the character of
drums or other percussion instruments.
Expander: e blue short-dash trace shows downward ex-
pansion with a ratio of 2:1. e signal is turned down gradually,
resulting in lower noise in the absence of signal while allowing
natural signal decay. Downward expansion generally uses a Re-
lease time of about 500 ms to 1 second and an Attack setting of
100 ms to 500 ms. e Hold function is not active when using
the Expander.
-80
+20
-70
-60
-50
-40
-30
-20
-10
0
+10
-60 +20-55-50 -45 -40 -35 -30-25 -20-15 -10-50+5 +10+15
INPUT dBu
SIDE-CHAIN INPUT
GATE
EXPANDER
THRESHOLD = 0 dBu
O
U
T
P
U
T
d
B
u
Manual-6
Duck Mode
Ducking reduces the level of a signal by a certain amount (the
depth) when the side-chain key signal exceeds a set threshold.
Ducking is useful for voiceover and instrument solo applications.
Example uses
• Automatically duck music when an announcement is made.
Connect the music signal to the main input, connect a signal
from the announcement microphone to the side-chain key
input. When the announcer speaks, the key input exceeds the
set threshold, and music is automatically turned down.
• Automatically duck the bass by a few dB every time the kick
drum is hit. Connect the bass to the main input, connect a
signal from the kick drum to the side-chain key input. Use a
relatively shallow depth.
Figure 5: Ducker
Kick Drum Attack Example
e pictures below show the aect of attack time on the leading
edge of a kick drum. e blue trace shows the Gate input signal.
e yellow trace shows the Gate output signal. e time dier-
ence between the two signals represents the total propagation
delay through the Gate. e Gate reshold is set to about 80%
of the peak value. e Gate Depth is 20 dB.
e rst complete cycle of the kick drum denes its sound, as
subsequent cycles are considerably lower in amplitude. e kick
drum’s sound is signicantly changed if the gate can not accu-
rately capture the rst cycle. Look ahead without ramping often
causes an audible click at fast attack and moderate to extreme
depth settings. Only look ahead pre-ramping – as done in the
G4 – accurately reproduces the 1st cycle of a kick drum without
adding excessive delay or signicantly altering the leading edge.
107405
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5000 USA TEL 425-355-6000 FAX 425-347-7757 WEB www.rane.com
e above graph shows the operation of the Ducker. A
Ducker works the opposite of a Gate. e signal is attenuated
when the side-chain key input goes above threshold. In the above
example, the dashed-line green trace shows the signal being
ducked. e solid-line red trace shows the external key input.
e threshold is set at –20 dBu. When the key input goes above
-20 dBu, the main signal is ducked by an amount set by the
depth control, in this case around 45 dB.
Note: All applications of ducking use the external side-chain key
input.
1m
20
10m
100m
1
5
V
-80
+20
-70
-60
-50
-40
-30
-20
-10
0
+10
-60 +20-55-50 -45-40 -35-30 -25-20 -15-10 -5 0+5 +10 +15
SIDE-CHAIN INPUT
DUCKED SIGNAL
INPUT dBu
O
U
T
P
U
T
d
B
u
The rst gure shows the response with a 0 ms attack time. The lead-
ing edge is dened by the look-ahead ramping. Note the leading edge
of the output is almost identical to the input signal.
The second gure shows the response with a 1 ms attack.
The slower rise time softens the sound of the leading edge.
msms
n:1
dB
Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
6 12-12 -6 -3 -1 31-24
dBu
6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
6 12-12 -6 -3 -1 31-24
dBu
6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
1 2
DEPTH
3 4
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
1 2
DEPTH
3 4
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
msms
n:1
dB
Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
6 12-12 -6 -3 -1 31-24
dBu
6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
MASTER SLAVE MASTER SLAVE
Sec
QUAD GATE
6 12-12 -6 -3 -1 31-24
dBu
6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24 6 12-12 -6 -3 -1 31-24
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
msms
n:1
dB
Hz Hz
SecdBu
-60
-20 -10-30
-40
-50 10
20
0
250
50
25 100
0
2 Sec
250
125 500
25 3
.5
.25 2
0
8
4
2 6
10
40
60 20
80 5k
315
80
1.25k
20 20k
2k
630
6.3k
200
G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
1 2
DEPTH
3 4
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
G4
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUT
1 2
DEPTH
3 4
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL
LINK LINK
DUCK EXPGATE
SIDE-CHAIN
POWER
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
ATTACK
RATIO
HOLDRELEASETHRESHOLD
LOW-CUT HIGH-CUTDEPTH
TH
CLOSED OPEN
SIDE-CHAIN dBr
BYPASSACTIVE EXTINT LISTENNORMAL DUCK EXPGATE
SIDE-CHAIN
OL
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