PowerAcoustik PEQ-72 User manual

INTRODUCTION
The PowerAcoustik Model PEQ-72 isintendedfor thosewho value the acoustic benefitsof amulti-bandGraphic
Equalizer but who also desire higher audio power level capabilities than can be obtained in an in-dash unit.
Itcontainstereo power amplifiersto drive speakers directly. and
1 subwoofer pair (with crossoversand sen-
sitivity control).Subwoofer output can
be connectedto remotehigh-poweramplifiers. The sevencenter-frequencies
are concentratedin.thecritical
60Hz to 15kHz region where compensation is most needed.

FEATURES AND OPERATING CONTROLS
1. FADER.Allowsfrontto rear balancinginfour speaker 5. ADJUSTABLE SUBWOOFER GAIN CONTROL.
systems for best directionalimaging. Allows user to adjust subwoofer output to match
2. EQ. Pressintoengagethe equalizercircuitry.Press overall system output.
it (outer position)the result isthe same as setting all
6. SPECTRUMANALYZER DISPLAY.A 5 coluns, Red-
slidecontrolsto center position. It is useful injudg- color LED Display shows the instantaneous, peak
ing the result of your EQ Settings. levelfor the frequency content of the sourcemusicad-
3. SUBWOOFER SWITCH dingyet another dimensionto your visual enjoyment.
When the subwoofer is connected, use this switch 7. EQ SLIDE CONTROLS. Each slide controls the
to activateldeactivate the subwoofer. amount of boostor cut inone small part of the total
4. SUBWOOFERCOSSOVER POINTS.Two operating audio frequency range. With all slides in the center
modes.The SUBWOOFER MODE activates aninter- position,the overall frequency response is tlat. By
nallow-passfilter so only'the deepest bass notesare moving any slide up or d~wn,the output within the
passedto the woofer system. Two position80Hz or band is increased or decreased by up to 12 db.
150Hz.

The PEQ-72isdesignedfor in-dashinstallationdirectly
above or belowa standardDIN size radioltapeplayer.
InstallationKitsfor the purposeareavailablefroma varie
ty of suppliers. Consult with a professionalAuto-sound
installer for assistance.
The Redwire with in-linefuse is the main power input
to the PEQ-72.It should be connected to a source of
Switched
+ 12volts (Cut off bythe Ignitionswitch). This
is normally the same fuse-panel terminal that powers
your radio.
Eachwire isindividuallylabeledto reduceany chance
of error. Phonocablepairswith plugs on bothends are
requiredto connect the PEQ-72outputsto the remote
amplifiers and also for the phono inputs if used. See
Figure
5. These can be purchasedfrom a local audio
dealer in the correct lengths for your particular
installation.
The Black wire labeled Power Ground is connected
directlytothe vehiclechassis. A secondBlackwire with
White stripelabeledSourceGroundis connectedto the
chassis of the in-dashradio. This dual-groundsystem
is helpful in reducing common sources of noise
generated by your vehicle.
The Orange wire is used on turn the PEQ-72On. It
shouldbeconnectedto the in-dashradio's Power Anten-
na Output Lead.
The final step inthe electrical installation is to connect
the Left
& Righr Output signals from your radio to the
PEQ-72.Inputsinone of two ways, depending on how
your radio is equipped. If it has Phono-styleLineOut-
puts, then they are connectedto the matchingLine In-
putsusinga purchasedcable pairas discussedabove
and shown in Figure
5.

OPERATIONAL CHECKS
Start with the radio off. Set the FADER and all seven
Normal Operation:
EQ SLIDES to their center positions.
Switchto ignitionor accessoryonandturnon the radio The purposeof a MULTI-BANDequalizeristocompen-
but at low volume. The light inthe PEQ-72should now sate for the fact that no speaker is perfect and, more
belit. If nothing happens,checkthe black, red,or orange importantly,that even a perfect speakerwill productim-
connectionsand the in-line fuses if necessary. perfect soundpressure levels versus frequency when
placedina real motor vehicle. It is possibleto correct
If all OK so far,then by raisingthe radiovolume should
producespeaker output. Next rotatethe radiobalance
controlto verify sound moves from full right to full left.
If itis reversedthen the inputstothe PEQ-72are revers-
ed. Ifyou are usingfour speakersthen rotatethe FADER
controlto verify the PEQ-72outputs are going to cor-
rect speakers.
SUBWOOFER OUTPUT: If you are usingthe subwoofer
output,try the two different settings. Each positionallows
adifferentrangeof bassfrequencythru. Becausedeep
bassstandsout morewe'veprovidedasubwoofergain
control.This will allow you to adjust the amount of bass
output neededto match the rest of your system.
these problems by boostingor cutting the speaker in-
put power at the proper frequencies. This is the basic
purpose of the power acoustik PEQ-72.
The task of findingthe best combination of EQ settngs
to producethe desiredresultequalsound-pressurelevels
at your ears for equal recorded signal level at any
frequency-dependsmainly on your ears. However, there
are several starting points to guide you.

INSTALLATION
1. Mostspeakersystemsrequirerather heavy boostat
the lowest frequencies duetothe largeamount of air
that must bemoved. However, speaker woofer cones
resontate between4560Hz where output is higher
so donot boosttoo much
at 60Hz. Useheavy boost
at 150Hz, Less boost at 400Hz.
2. Dueto sound-wavereflectionsbetweenthefront and
rear windshieldsof a typical vehicle, there may be
heavy loss between 700Hz to 1.3kHz so moderate
boost here is very effective and will create more
"presence" for vocalists.
3. The mid-rangefrom 3 to 6kHz should not require
muchchangefrom flat (center) Mostspeakerswork
well here. Adjust per your taste.
1
4. Due to limitationsin human hearing. sound above
I
8kHzis not heardvery well. Moderateboostat 1kHz
addsa crisp charactrwhen percussion instruments
are present.

SPECIFICATIONS
EQUALIZER
Center Frequencies: 60,150.400.1K92.5K.6K,15KHz.
Equalization Range: +I - 12dB nom, at each center freq.
High level Inputs: Impedance: 100 ohms
Max. Sensitivity:
3 volts nom. for full output.
Low level Inputs: Impedance: 12K ohms
Max. Sensitivity: 500mv. nom. for full output
Crossover Rolloff: 12 dBloctave
POWER AMPLIFIER
Output Power: 50 watts maximum per channel into
4 ohms. 18 watts per channel at less
than 1% THD. (14.0 volts D.C. Supply)
Frequency Response: 20Hz to 20KHz.
+I- 3 dB at 1
watt.
Residual Output Noise: Less than 1.OmV UNWEIGHTED with slide controls at center position.
Power Requirement: 11-1 6 volts D.C. negative ground. 5 amps maximum.
Accessories Included: Mounting Brackets, Hardware, Installation instructions.
Dimensions (Wx H x D): 7" x 1 " x 5-112"
178x25~141mm
Due to our continuing effortstowards product improvement, the above specifications are subject to change
without notice.