Mackie QUAD EQ User manual
OWNER’S MANUAL
4-CHANNEL DIGITAL GRAPHIC EQUALIZER
QUAD EQ
2
QUAD EQ
Quad EQ
3
Owner’s Manual
Owner’s Manual
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 dry cloth.
7. Do not block any ventilation openings. Install in accordance with the
manufacturer’s instructions.
8. Do not install near any heat sources such as radiators, heat 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.
The wide blade or the third prong are 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 from being walked on or pinched particularly at
plugs, convenience receptacles, and the point where they exit from the
apparatus.
11.
Only use attachments/accessories specied by the manufacturer.
12.
Use only with a 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.
This apparatus shall not be exposed to dripping or splashing, and no
object lled with liquids, such as vases or beer glasses, shall be placed
on the apparatus.
16.
This apparatus has been designed with Class-I construction and must
be connected to a mains socket outlet with a protective earthing con-
nection (the third grounding prong).
17.
This apparatus has been equipped with an all-pole, rocker-style AC
mains power switch. This switch is located on the rear panel and
should remain readily accessible to the user.
18.
This apparatus does not exceed the Class A/Class B (whichever is
applicable)
limits for radio noise emissions from digital apparatus as
set out in the radio interference regulations of the Canadian Department
of Communications.
ATTENTION — Le présent appareil numérique n’émet pas de bruits
radioélectriques dépassant las limites applicables aux appareils numériques de
class A/de class B (selon le cas) prescrites dans le réglement sur le brouillage
radioélectrique édicté par les ministere des communications du Canada.
19.
Exposure to extremely high noise levels may cause permanent hearing
loss. Individuals vary considerably in susceptibility to noise-induced
hearing loss, but nearly everyone will lose some hearing if exposed to
sufciently intense noise for a period of time. The U.S. Government’s
Occupational Safety and Health Administration (OSHA) has specied
the permissible noise level exposures shown in the following chart.
According to OSHA, any exposure in excess of these permissible limits
could result in some hearing loss. To ensure against potentially danger-
ous exposure to high sound pressure levels, it is recommended that all
persons exposed to equipment capable of producing high sound pres-
sure levels use hearing protectors while the equipment is in operation.
Ear plugs or protectors in the ear canals or over the ears must be worn
when operating the equipment in order to prevent permanent hearing
loss if exposure is in excess of the limits set forth here.
Important Safety Instructions
Duration Per Day Sound Level dBA, Typical
In Hours Slow Response Example
8 90 Duo in small club
6 92
4 95 Subway Train
3 97
2 100 Very loud classical music
1.5 102
1 105 Dave screaming at Steve about deadlines
0.5 110
0.25 or less 115 Loudest parts at a rock concert
WARNING — To reduce the risk of re or
electric shock, do not expose this apparatus
to rain or moisture.
PORTABLE CART WARNING
Carts and stands - The
Component should be used
only with a cart or stand
that is recommended by
the manufacturer.
A Component and cart
combination should be
moved with care. Quick
stops, excessive force, and
uneven surfaces may cause
the Component and cart
combination to overturn.
CAUTION AVIS
RISK OF ELECTRIC SHOCK
DO NOT OPEN
RISQUE DE CHOC ELECTRIQUE
NE PAS OUVRIR
CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK
DO NOT REMOVE COVER (OR BACK)
NO USER-SERVICEABLE PARTS INSIDE
REFER SERVICING TO QUALIFIED PERSONNEL
ATTENTION: POUR EVITER LES RISQUES DE CHOC
ELECTRIQUE, NE PAS ENLEVER LE COUVERCLE. AUCUN
ENTRETIEN DE PIECES INTERIEURES PAR L’USAGER. CONFIER
L’ENTRETIEN AU PERSONNEL QUALIFIE.
AVIS: POUR EVITER LES RISQUES D’INCENDIE OU
D’ELECTROCUTION, N’EXPOSEZ PAS CET ARTICLE
A LA PLUIE OU A L’HUMIDITE
The lightning flash with arrowhead symbol within an equilateral
triangle is intended to alert the user to the presence of uninsulated
"dangerous voltage" within the product’s enclosure, that may be
of sufficient magnitude to constitute a risk of electric shock to persons.
Le symbole clair avec point de fl che l’int rieur d’un triangle
quilat ral est utilis pour alerter l’utilisateur de la pr sence
l’int rieur du coffret de "voltage dangereux" non isol d’ampleur
suffisante pour constituer un risque d’ l ctrocution.
The exclamation point within an equilateral triangle is intended to
alert the user of the presence of important operating and maintenance
(servicing) instructions in the literature accompanying the appliance.
Le point d’exclamation l’int rieur d’un triangle quilat ral est
employ pour alerter les utilisateurs de la pr sence d’instructions
importantes pour le fonctionnement et l’entretien (service) dans le
livret d’instruction accompagnant l’appareil.
4
QUAD EQ
Quad EQ
4
QUAD EQ
Quad EQ
5
6
QUAD EQ
Quad EQ
7
Owner’s Manual
Owner’s Manual
Hookup Diagrams
6
QUAD EQ
Quad EQ
7
Owner’s Manual
Owner’s Manual
FRONT OF HOUSE MAIN MIX EQ
8
QUAD EQ
Quad EQ
9
Owner’s Manual
Owner’s Manual
STUDIO TUNING
8
QUAD EQ
Quad EQ
9
Owner’s Manual
Owner’s Manual
Rear Panel Features
1. AC Input receptacle
This is a standard 3-prong IEC power connector. Con-
nect the detachable linecord (included in the box with
your Quad EQ) to this power receptacle, and plug the
other end of the linecord into an AC outlet.
The Quad EQ has a universal power supply that can
accept any AC voltage from 100 VAC to 240 VAC.
It will work virtually anywhere in the world, includ-
ing Walton-on-the-Naze, England. That’s why we call it
a “Planet-Earth” power supply! The power supply is less
susceptible to voltage sags or spikes than conventional
supplies, providing greater electromagnetic isolation
and better protection against AC line noise.
2. Power switch
Press the top edge of this rocker switch in to turn on
the Quad EQ.
Turn it off by pressing the bottom edge of the rocker
switch. Audio will still pass through even when the Quad
EQ is turned off.
3. Measurement Microphone input
This XLR-male jack is used to connect the supplied
RA-420 measurement microphone.
The microphone preamplier circuit has been opti-
mised to work with the supplied microphone: it has a
xed gain setting, and 48 V phantom power is applied at
all times.
When the front panel MIC button is engaged, the
microphone signals from the measurement microphone
will enter the Quad EQ for real time analysis, and the
other inputs are disconnected and will not play through
the Quad EQ.
Rear Panel Ins and Outs (channels A-D)
The IN and OUT jacks will pass through
signals if the power is not applied to the
Quad EQ. For example, if your mixer’s left
main output is coming into the Quad EQ channel-A in-
put, and the Quad EQ is off, the same signal will appear
at the channel-A output jack.
These inputs and outputs are line-level,
and you would normally connect them to a
mixer or line-level component in your sys-
tem. Do not connect microphones or instru-
ments directly to the inputs.
4. TRS Inputs and 5. XLR Inputs
These 1/4" TRS (tip-ring-sleeve) jacks are the inputs
for the channels. They can accept balanced TRS plugs,
or unbalanced 1/4" TS (tip-sleeve) plugs, tip hot.
The female XLR jacks are also the inputs for the chan-
nels (pin 2 hot, pin 3 cold, pin 1 shield).
For each channel, the XLR and TRS inputs are in
parallel, so you can choose either style as an input. You
can use unbalanced TS connections, but we recommend
using balanced connections wherever possible.
6. TRS outputs and 7. XLR Outputs
These 1/4" TRS jacks are the outputs for the channels.
They can accept balanced TRS plugs, or unbalanced
1/4" TS plugs, tip hot.
The male XLR jacks are also the outputs for the chan-
nels.
For each channel, the balanced XLR and TRS outputs
are in parallel, so you can choose either style of output.
Both TRS and XLR outputs can be used simultaneously.
10
QUAD EQ
Quad EQ
11
Owner’s Manual
Owner’s Manual
Front Panel Controls
Filters
The Quad EQ has thirty Adaptive-Q lters across the
audio frequency range, for each of the four channels.
Each lter can be adjusted in level from 12 dB of boost
to 12 dB of cut. The Adaptive-Q design allows the actual
equalization applied to your signal to follow the settings
you see in the display, without the ripples and gain boost
found in many common EQs. The lter frequencies are
as follows from left to right:
8. FILTER LED ladders
Each LED ladder contains 11 bi-colored (green/red)
LEDs that show various settings of the Quad EQ. There
is one LED ladder per lter, and they all function in the
same way except for the right-most ladder (see MAS-
TER [9] below).
When setting the EQ level of each lter, the LEDs
glow red. They move above the center (0 dB) line when
applied as a boost in level, and below it when applied
as a cut. Each lter is capable of ±12 dB boost and cut,
achieved by pressing the button beneath the lter of
interest, and then turning the KNOB [19].
For real time analysis (RTA) applications, the LEDs
turn green. They ll from bottom to top to show broad-
band frequency analysis. The LEDs show the signal
levels of each lter from the current channel. If you are
using the MIC, then the LEDs show the signal levels of
each lter from the measurement microphone.
The Quad EQ can display both the EQ setting and RTA
results simultaneously, making it an extremely unique
live sound tool. The EQ settings are displayed as a single
red LED per ladder, while the RTA (green) LEDs will
actively display around the EQ setting.
9. MASTER LED Ladder
The right-most LED ladder shows the master output
level setting in red, and the master output meter in
green. It is like having a master fader and master meter
in one.
The level control setting is red, with unity (0 dB) at
the center and a range of ±12 dB. The adjustment is
made by pressing the MASTER SELECT [11] switch
below this LED ladder, and turning the KNOB [19].
The green output level metering is always in view,
showing the average signal level across the complete
audio frequency range, with 0 dB at the top, to -50 dB.
This right-most ladder is more to the right than any
other ladder, and no other ladder is more right-most
than it, being all leftwards.
10. FILTER SELECT buttons and LEDs
To adjust the level of a lter, press one of these but-
tons, and turn the KNOB [19]. The dB level (±12) ap-
pears temporarily in the DISPLAY [20] above the KNOB.
The LED above each button illuminates when that lter
is selected.
There are different options, such as grouping lters,
setting a lter to 0 dB, and setting all lters to 0 dB:
Group lter select
Press and hold a FILTER SELECT button and press
any others to create a temporary group of lters.
These can then all be adjusted at the same time us-
ing the KNOB. The lters will maintain their relative
positions during adjustment, allowing you to keep an
EQ curve the way you like, but still boost or cut the
lters. Pressing any single FILTER SELECT button
will remove the group setting.
10
QUAD EQ
Quad EQ
11
Owner’s Manual
Owner’s Manual
You can also select a group of lters by holding one,
then turning the KNOB to select a band of adjacent
lters. Let go of the rst one, then turn the KNOB to
adjust the level of this group.
Setting a lter to 0 dB
Press and hold the EDIT [13] button and any
FILTER SELECT button to return that lter to unity
(0 dB).
Setting all lters to 0 dB
Press and hold the EDIT [13] button and the MAS-
TER SELECT [11] button to reset all the channel
lters to unity (0 dB).
11. MASTER SELECT button and LED
Press this button to select the main output, then turn
the KNOB [19] to adjust the main output level. The
dB reading (±12) appears temporarily in the DISPLAY
above the KNOB.
12. CHANNEL SELECT buttons A/B/C/D
These backlit buttons allow you to select the channel
to be adjusted.
There are options to link pairs in stereo, and to lock a
channel as follows:
Stereo Linking
Pressing and holding A and B at the same time will
link/unlink these channels in stereo. When linked,
the pair take on channel A’s settings.
Pressing and holding C and D at the same time will
link/unlink these channels in stereo. When linked,
the pair take on channel C’s settings.
If two channels are linked, then any changes to the
lters will affect both channels equally.
If you use the NOISE function, then the noise will be
present in both of the linked channels.
Locking a channel
Press and hold the EDIT [13] button and A, B, C or
D to lock/unlock that channel.
A channel is unlocked when the channel A-D buttons
are lit solid, and it is locked when they are blinking.
When a channel is locked, its lters cannot be edited
until it is unlocked using the same press-and-hold
method.
Function Buttons
The function buttons include RTA [17], MIC [18],
NOISE [15], FILTER [16], and EDIT [13].
These buttons have two modes of operation:
1. Pressing the RTA, MIC, and FILTER buttons
toggles them on/off (the button lights when
on). To activate the noise feature, press a chan-
nel button rst (A, B, C or D), then NOISE.
2. Pressing EDIT and then any of the four func-
tions allows deeper access to the settings of
these functions. Details below…
13. EDIT button
This button is your friend. It lets you access the extra
features of the other function buttons. Press EDIT
rst, followed by a button such as RTA [17], MIC [18],
NOISE [15], or FILTER [16]. What happens then is
described in the sections below, under Noise Edit, RTA
Edit, MIC Edit, and Filter Edit. (See back cover table.)
EDIT blinks when engaged, and while it is blinking
you can jump around to any mode to make adjustments.
For example, you can adust RTA, NOISE and FILTER all
without quitting the EDIT mode.
To quit the EDIT mode, you can press EDIT again, or
press the KNOB [19] in. (Its a knob and a button, wow!)
14. BYPASS button
Press this button to bypass the currently-selected EQ
channel. The incoming signals will pass through to the
outputs of the Quad EQ, without being affected by any
changes in EQ or other controls. The button will illumi-
nate when a channel is bypassed.
The channel will stay bypassed even when another
channel is selected, and recalled when the channel is
reselected. Press BYPASS again to leave Bypass mode.
12
QUAD EQ
Quad EQ
13
Owner’s Manual
Owner’s Manual
15. NOISE button
1. Press a CHANNEL SELECT Button (A, B, C or
D) and the NOISE button, then several inter-
esting things will happen:
• The audio input to the currently-selected chan-
nel is interrupted.
• Pink noise appears at the output of the Quad
EQ to play in your speaker system.
• Press RTA if you want to see this noise.
• If you have stereo-linked channels, then the
noise will appear in both channels.
• The microphone input is still live, allowing you
to use the microphone to sample the noise play-
ing in your system. (Press Mic to do this.)
• If the audience is present, you may be tarred
and feathered (unless the noise is an improve-
ment over the band).
The default level is off, and it needs to be edited to
adjust the level of the noise (see below). Once it has
been set to a suitable level, and you follow the rst step
to turn on the noise, it will turn on at the last level it
was set to.
When the noise is playing, you can use the measure-
ment microphone to set up, analyze, and equalize your
system. You will often have NOISE and MIC selected at
the same time. The response from your microphone will
show the effect of room reections, standing waves, and
the output characteristics of your speakers, boosting
and cutting the level across the frequency band. You can
then use the Filter buttons to adjust the EQ of problem
areas. For example, if a large level boost is present in a
certain frequency range, this area will be more suscept-
able to feedback. See details of the MIC button for more
information about using the measurement microphone.
12
QUAD EQ
Quad EQ
13
Owner’s Manual
Owner’s Manual
16. FILTER button
This button provides you with access to the variable
high-pass and low-pass lters of the current EQ chan-
nel. Pressing the FILTER button engages and disengages
these two pass lters at their currently edited settings.
For the high-pass lter, the signal level of the fre-
quency range below the lter frequency is attenuated by
an amount determined by the high-pass lter slope. In
other words, it rolls off the lows (less boom-boom).
The high-pass lter can be used to reduce any low-
frequency effects such as stage rumble, or microphone
handling. In another example, you might have speakers
which do not reproduce frequencies below 60 Hz very
well. You can set the high-pass lter frequency to 60 Hz,
so your ampliers do not receive much signal level at
frequencies below this, and do not waste power. They
will have more power reserves for the frequency range
your speakers can reproduce well.
For the low-pass lter, the signal level of the fre-
quency range above the lter frequency is attenuated
by an amount determined by the low-pass lter slope. In
other words, it rolls off the highs (less tweeter tribble).
For example, you can reduce the really high frequen-
cies upsetting the local cat population, and protect your
tweeters at the same time.
With both of these lters, you can still adjust the EQ
levels of individual lters as desired.
To get a better idea of the effect of your lter settings,
on your audio, you may want to engage the RTA and see
what’s happening.
FILTER EDIT functions
The frequency and slope of the high-pass and low-pass
lters can be adjusted as follows:
1. Press EDIT [13] (blinks) and FILTER (blinks)
to get to the rst option shown in the DISPLAY
[20]. Use the KNOB [19] to adjust its param-
eter.
2. Each time you press FILTER, you move to the
next option to be adjusted, The options are as
follows, in the order in which they appear: HPF,
LPF, HPs and LPs.
3. Press the KNOB or EDIT to exit the edit mode.
HPF (High-pass lter frequency)
The KNOB and DISPLAY allow adjustment and
display of the HPF frequency. The range is 20 Hz to
3 kHz
LPF (Low-pass lter frequency)
The KNOB and DISPLAY allow adjustment and
display of the LPF frequency. The range is 1 kHz to
20 kHz
HPs (High-pass lter slope)
The KNOB and DISPLAY allow you to change the
high-pass lter’s slope between 12 dB and 24 dB per
octave. (This is the rate of signal attenuation for fre-
quencies lower than the high-pass lter’s frequency.)
LPs (Low-pass lter slope)
The KNOB and DISPLAY allow you to change the
low-pass lter’s slope between 12 dB and 24 dB per
octave. (This is the rate of signal attenuation for fre-
quencies higher than the low-pass lter’s frequency.)
14
QUAD EQ
Quad EQ
15
Owner’s Manual
Owner’s Manual
17. RTA button
Pressing this button engages the real time analysis
function, and lights the button solid. The RTA looks at
the input signal of the currently-selected channel. It is
not related to the external measurement mic input. The
RTA and MIC buttons operate in an exclusive manner,
meaning only one can be active at any given time.
The 30 LED ladders display the levels of the currently
selected channel. The ladders are then like a graph of
the received signal’s frequencies from 20 Hz to 20 kHz,
split up into 30 bands, vs. the signal level of each band.
RTA EDIT functions
There are four options for the RTA described below:
1. Press EDIT [13] (blinks) and RTA (blinks) to
get to the rst option shown in the DISPLAY
[20]. Use the KNOB [19] to adjust its param-
eter.
2. Each time you press RTA, you move to the next
option to be adjusted, The options are as fol-
lows, in the order in which they appear: REF,
DCY, EQ, and EQD.
3. Press the KNOB or EDIT to exit the edit mode.
REF (Reference level)
This option allows you to adjust the RTA reference
level (–60 dB to 0 dB) with the KNOB. This allows
you to get the analyzed signal into the best range for
viewing on the LED ladders.
If you turn the KNOB a little, you can press and hold
the RTA button to auto-reference level the RTA. This
will take an average of the analyzed signal and set
the reference level automatically.
DCY (RTA decay)
This option provides 4 decay settings for the RTA you
can choose with the KNOB:
• Off is straight metering of the signal.
• On1 displays metering plus a peak-and-hold
function with a slow decay.
• On2 displays metering plus a peak-and-hold
with a fast decay.
• On3 is a peak-and-hold with no decay.
EQ (pre/post EQ RTA analysis)
This option allows the RTA to be applied to the input
signal either pre-EQ or post-EQ.
A pre-EQ RTA signal is great way to view the signal
as it enters the EQ. This can be used to see the
frequency response of the raw signal coming into the
Quad EQ.
The post-EQ setting (the factory default) is very
valuable, as the RTA will respond to lter changes.
This can be useful for graphic EQs for monitor wedge
mixes. A feedback frequency can be easily identied
and cut using the Quad EQ in this way.
EQD (EQ display)
This option allows you to turn off the EQ lter set-
ting display during RTA operation, so you can oper-
ate the device purely as an RTA.
Although the EQ lters are still applied to the signal,
the display only shows RTA information.
If you have turned off the EQ display with this fun-
tion, it will still come back on for a few seconds each
time you press or adjust a lter EQ. This reminds you
what the EQ settings were, even when the display
has been turned off.
14
QUAD EQ
Quad EQ
15
Owner’s Manual
Owner’s Manual
18. MIC button
Pressing this button will engage the measurement mi-
crophone input as the source for the analysis function,
and it will light the button solid.
The gain structure for this microphone input is set for
the included measurement microphone, and 48 V phan-
tom power is continuously applied to the input.
The RTA [17] and MIC buttons operate in an exclu-
sive manner, meaning only one of the two functions can
be active at any given time.
Engaging the MIC button also turns the DISPLAY [20]
into a dB-Sound Pressure Level (SPL) meter. It displays
“lo” when the received SPL is under 70 dB, and ranges
between 70 and 120 dB when the signal is present.
MIC EDIT functions
The MIC function has two edit functions:
1. Press EDIT [13] (blinks) and MIC (blinks) to
get to the rst option (ref) in the DISPLAY. Use
the KNOB [19] to adjust its parameter.
2. Press MIC again to select the next option (SPL)
to be adjusted.
3. Press the KNOB or EDIT to exit the edit mode.
ref (MIC reference level)
This option allows you to adjust the MIC reference
level (–60 to 0 dB) with the KNOB to get the ana-
lyzed signal into the best range for viewing on the
LED ladders.
If you can see the SPL level reading, but there is no
display in the LED ladders, adjust this level to bring
it up from the depths and into view.
SPL (dB-SPL weighting)
This option allows you to choose A, B, or C weighting
for the SPL meter. Use the KNOB to scroll through
the 3 options.
“Weighting” is a curve of correction factors applied
across the frequency band to accommadate the per-
formance and perception of the human ear.
Generally, you can think of the A-weighting as a
correction for our perception at lower SPL levels,
B-weighing for medium levels, and C-weighting for
high levels.
A-weighting: Human beans can perceive loudness
more in the mid-range frequencies than the highs
or lows, so the A-weighting curve rolls off the highs
and lows. When noise levels are specied in hearing
protection ratings for example, these are usually A-
weighted, and commonly displayed as dBA.
B-weighting is similar to the A-weighting, only with
less attenuation of the lows and highs.
C-weighting is fairly at, but with limited bandwidth.
It is often used to simulate what we perceive at high
decibel levels, and is commonly displayed as dBC.
You can switch between the settings, and gain some
insight into what is going on in your system. For
example, if a C-weighted SPL reading is much higher
than an A-weighted reading of the same system, then
there must be a fair amount of low-frequency energy
present (rolled-off more by the A-weighting than the
C). If the C and A-weighted SPL readings are similar,
then the main content must be in the mid-range.
Here is an approximate graph of the correction
curves applied to the measurements across the
frequency range.
16
QUAD EQ
Quad EQ
16
QUAD EQ
Quad EQ
17
Owner’s Manual
Owner’s Manual
Appendix A: Service Information
Warranty Service
Details concerning Warranty Service are spelled out in
the Warranty section on page 23.
If you think your Quad EQ has a problem, please do ev-
erything you can to conrm it before calling for service.
Doing so might save you from the deprivation of your
Quad EQ and the associated suffering.
These may sound obvious to you, but here are some
things you can check. Read on:
Troubleshooting
No Power
• Our favorite question: Is it plugged in?
• Make sure the power cord is securely seated in the
IEC socket and plugged all the way into the AC
outlet.
• Make sure the AC outlet is live (check with a tester
or lamp).
• Make sure the rear panel POWER [2] switch is in
the ON position.
• Is anything on the front panel illuminated? If not,
make sure the AC outlet is live.
• Are all the lights out in your town? If so, contact
your local power company to get power restored.
• If nothing is illuminated, and you are certain that
the AC outlet is live, it will be
necessary to have
your Quad EQ serviced. There are no user serviceable
parts inside. Refer to “Repair” on the next page to
nd out how to proceed.
Bad Channel
• If one channel sounds bad, try pressing BYPASS
[14] on that channel. If it improves things, care-
fully check your settings on that channel.
• Look at the MASTER LED [9] ladder and check
and adjust the level if needed.
• Check there are no extreme settings of the EQ
lters or the high-pass or low-pass lters.
• Check that NOISE [15] is not engaged.
• Check that MIC [18] is not engaged.
• Try turning the Quad EQ off. The connections be-
tween the input and output are then joined inter-
nally, and this should allow your mixer and amps to
still play. If a channel is still missing, you may have
a bad connction cable either into or out of the Quad
EQ, or a bad mixer output or amplier.
• Try the same source signal in another channel, set
up exactly like the suspect channel.
Bad Output
• Are the MASTER [9] levels for the channels turned
up?
• If it’s one of the outputs, try unplugging the others.
For example, if it’s an XLR output, try unplugging
any TRS outputs if used. If the problem goes away,
it’s not the Quad EQ.
• If a left output is presumed dead, switch the left
and right cords at the Quad EQ end. If the problem
stays on the left side, it’s not the Quad EQ, but
maybe the left amplier channel, a bad cord, or left
speaker.
Bad Sound
• Are the input and output connectors plugged com-
pletely into the jacks?
• Press BYPASS [14] and listen for any improvement.
• If possible, listen to the signal with headphones
plugged into the input source device or mixer. If it
sounds bad there, it’s not the Quad EQ causing the
problem.
• Have you gone a tad overboard with the EQ set-
tings? Cut is our friend, and boost should be used
wisely.
• Has the band been together long?
Noise/Hum
• Turn down each channel, one by one. If the noise
disappears, it’s coming from whatever is plugged
into that channel. Check your whatever.
• Check the signal cables between the mixer and the
Quad EQ. Disconnect them one by one. If the noise
goes away, you’ll know which input is causing the
problem.
• Sometimes it helps to plug all the audio equipment
into the same AC circuit so they share a common
ground.
18
QUAD EQ
Quad EQ
19
Owner’s Manual
Owner’s Manual
Repair
Service for Mackie products is available at a factory-
authorized service center. Service for Mackie products
living outside the United States can be obtained through
local dealers or distributors.
If your Quad EQ needs service, follow these instructions:
1. Review the preceding troubleshooting suggestions.
Please.
2. Call Tech Support at 1-800-898-3211, 7 am to 5 pm
PST, to explain the problem and request a Service
Request Number. Have your serial number ready.
You must have a Service Request Number before
you can obtain warranty service.
3.
Keep this owner’s manual and the detachable
linecord. We don’t need them to repair the Quad EQ.
4. Pack the Quad EQ in its original package, includ-
ing endcaps and box. This is VERY IMPORTANT.
Mackie is not responsible for any damage that
occurs due to non-factory packaging.
5. Include a legible note stating your name, shipping
address (no P.O. boxes), daytime phone
number,
Service Request Number, and a detailed description
of the problem, including how we can duplicate it.
6.
Write the
Service Request Number
in BIG PRINT on
top of the box. Units sent without the SR number will
be refused.
7. Tech Support will tell you where to ship the Quad
EQ for repair. We suggest insurance for all forms of
cartage.
8. You will need to contact the authorized service cen-
ter for their latest turn-around times.
The Quad EQ
must be packaged in its original packing box, and
must have the
Service Request Number
on the box.
Once it’s repaired,
the authorized service center
will ship it back by ground shipping, pre-paid (if it
was a warranty repair).
Note: Under the terms of the warranty, you must ship
or drop-off the unit to an authorized service center.
The return ground shipment is covered for those
units deemed by us to be under warranty.
Note: You must have a sales receipt from
an authorized Mackie dealer for your
unit to be considered for warranty
repair.
Need Help?
You can reach a technical support representative
Monday through Friday
from 7 AM to 5 PM PST at:
1-800-898-3211
After hours, visit www.mackie.com and click Support,
or email us at: techmail@mackie.com
18
QUAD EQ
Quad EQ
19
Owner’s Manual
Owner’s Manual
Appendix B: Connections
XLR Connectors
The Quad EQ inputs accept 3-pin male XLR connec-
tors. These are wired as follows, according to standards
specied by the AES (Audio Engineering Society).
2
2
31
1
SHIELD
COLD
HOT
20
QUAD EQ
Quad EQ
21
Owner’s Manual
Owner’s Manual
Specications
Frequency Response
15 Hz-20 kHz ±0.2 dB
THD
0.01% (15 Hz-20 kHz)
Signal to Noise Ratio
Analog in to Analog out, ref to +4 dBu: 104 dB
Propagation delay
3.2 mS
EQ lters
30 Adaptive-Q lters, ±12 dB range
HPF 20 Hz -3 kHz, 12 or 24 dB/octave Linkwitz-Riley
LPF 1 kHz-20 kHz, 12 or 24 dB/octave Linkwitz-Riley
Analog inputs:
Connectors: XLR female & TRS
Max input level: +22 dBu
Input level range: ±15 dB digital trim
Impedance: 10k ohms
A/D:
24-bits (20 Hz-20 kHz, ±1 dB)
Dynamic Range: 106 dB
Crosstalk: –110 dB @ 1 kHz
Measurement mic input
Connector: XLR female
Gain: Fixed at appropriate level for supplied Mic
Impedance: 10k ohms
Phantom Power: 48 V applied continuously
Appendix C: Technical Info
Analog Outputs:
Connectors: XLR male & TRS
Max output level: +22 dBu balanced, +20 dBu unbalanced
Impedance: 150 ohms
D/A:
24-bits (20-20 kHz, +/-1 dB)
Dynamic Range: 108 dB
Crosstalk: –115 dB @ 1 kHz
Sample Rates: 48 kHz
Digital Signal Processing: 32-bit oating point
Power:
100-240 VAC, 50/60 Hz auto-switching
Dimensions:
Width 19 inches (483 mm)
Height 3.5 inches (88 mm)
Depth 10.7 inches (271 mm)
Weight: 10 lbs (4.6 kg)
LOUD Technologies Inc. is always striving to improve our prod-
ucts by incorporating new and improved materials, components,
and manufacturing methods. Therefore, we reserve the right to
change these specications at any time without notice.
“Mackie,” and the “Running Man” are registered trademarks of
LOUD Technologies Inc. All other brand names mentioned are
trademarks or registered trademarks of their respective hold-
ers, and are hereby acknowledged.
©2005 LOUD Technologies Inc. All Rights Reserved.
Other manuals for QUAD EQ
1
Table of contents
Other Mackie Stereo Equalizer manuals
