Power Acoustik PEQ-72 User Manual

INTRODUCTION

The Power Acoustik Model
Equalizer but who also desire higher audio power level capabilities than can be obtained in an in-dash unit.
It contain stereo power amplifiers to drive speakers directly. and
sitivity control). Subwoofer output can
are concentrated in

PEQ-72

.the critical

is intended for those who value the acoustic benefits of a multi-band Graphic

1

be

connected to remote high-power amplifiers. The seven center-frequencies

60Hz

to

15kHz

region where compensation is most needed.

subwoofer pair (with crossovers and sen-

FEATURES AND OPERATING CONTROLS

1. FADER. Allows front to rear balancing in four speaker
systems for best directional imaging.

2.

EQ.

Press in to engage the equalizer circuitry. Press
it (outer position) the result is the same as setting all
slide controls to center position. It is useful in judg­ing the result of your EQ Settings.

3.

SUBWOOFER SWITCH
When the subwoofer is connected, use this switch
to activateldeactivate the subwoofer.

4. SUBWOOFER COSSOVER POINTS. Two operating

modes. The SUBWOOFER MODE activates an inter­nal low-pass filter so only'the deepest bass notes are
passed to the woofer system. Two position 80Hz or

150Hz.

5.

ADJUSTABLE SUBWOOFER GAIN CONTROL.
Allows user to adjust subwoofer output to match

overall system output.

6.

SPECTRUM ANALYZER DISPLAY. A 5 coluns, Red­color LED Display shows the instantaneous, peak
level for the frequency content of the source musicad­ding yet another dimension to your visual enjoyment.

7. EQ SLIDE CONTROLS. Each slide controls the

amount of boost or cut in one small part of the total
audio frequency range. With all slides in the center
position, the overall frequency response is tlat. By
moving any slide up or d~wn, the output within the
band is increased or decreased by up to 12 db.

The PEQ-72 is designed for in-dash installation directly
above or below a standard DIN size

Installation Kits for the purpose are available from a

ty

of suppliers. Consult with a professional Auto-sound

installer for assistance.

Each wire is individually labeled to reduce any chance

of error. Phono cable pairs with plugs on both ends are

required to connect the PEQ-72 outputs to the remote
amplifiers and also for the phono inputs if used. See
Figure

5.

dealer in the correct lengths for your particular
installation.

The Black wire labeled Power Ground is connected
directly to the vehicle chassis. A second Black wire with
White stripe labeled Source Ground is connected to the
chassis of the in-dash radio. This dual-ground system
is helpful in reducing common sources of noise
generated by your vehicle.

These can be purchased from a local audio

radioltape player.

varie

The Red wire with in-line fuse is the main power input
to the PEQ-72. It should be connected to a source of
Switched
is normally the same fuse-panel terminal that powers
your radio.

The Orange wire is used on turn the PEQ-72 On. It
should be connected to the in-dash radio's Power Anten­na Output Lead.

The final step in the electrical installation is to connect
the Left
PEQ-72. Inputs in one of two ways, depending on how

your radio is equipped. If it has Phono-style Line Out­puts, then they are connected to the matching Line In­puts using a purchased cable pair as discussed above
and shown in Figure

+

12 volts (Cut off by the Ignition switch). This

&

Righr Output signals from your radio to the

5.

OPERATIONAL

CHECKS

Start with the radio off. Set the FADER and all seven
EQ SLIDES to their center positions.

Switch to ignition or accessory on and turn on the radio
but at low volume. The light in the PEQ-72 should now
be lit. If nothing happens, check the black, red, or orange
connections and the in-line fuses if necessary.

If all OK so far, then by raising the radio volume should
produce speaker output. Next rotate the radio balance

control to verify sound moves from full right to full left.

If it is reversed then the inputs to the PEQ-72 are revers­ed. If you are using four speakers then rotate the FADER
control to verify the PEQ-72 outputs are going to cor-

rect speakers.

SUBWOOFER OUTPUT: If you are using the subwoofer

output, try the two different settings. Each position allows

a different range of bass frequency thru. Because deep

bass stands out more we've provided a subwoofer gain

control. This will allow you to adjust the amount of bass

output needed to match the rest of your system.

Normal Operation:

The purpose of a MULTI-BAND equalizer is to compen­sate for the fact that no speaker is perfect and, more
importantly, that even a perfect speaker will product im-

perfect soundpressure levels versus frequency when
placed in a real motor vehicle. It is possible to correct

these problems by boosting or cutting the speaker in-

put power at the proper frequencies. This is the basic
purpose of the power acoustik PEQ-72.

The task of finding the best combination of EQ settngs
to produce the desired resultequal sound-pressure levels
at your ears for equal recorded signal level at any
frequency-depends mainly on your ears. However, there
are several starting points to guide you.

1

I

1. Most speaker systems require rather heavy boost at
the lowest frequencies due to the large amount of air
that must be moved. However, speaker woofer cones
resontate between
so do not boost too much
at

150Hz, Less boost at 400Hz.

2. Due to sound-wave reflections between the front and
rear windshields of a typical vehicle, there may be
heavy loss between
boost here is very effective and will create more
"presence" for vocalists.

3.

The mid-range from 3 to 6kHz should not require
much change from flat (center) Most speakers work
well here. Adjust per your taste.

4. Due to limitations in human hearing. sound above
8kHz is not heard very well. Moderate boost at 1 kHz
adds a crisp charactr when percussion instruments
are present.

4560Hz where output is higher

at

60Hz. Use heavy boost

700Hz to 1.3kHz so moderate

INSTALLATION

SPECIFICATIONS

EQUALIZER

Center Frequencies:

Equalization Range:
High level Inputs:

Low level Inputs: Impedance: 12K ohms

Crossover Rolloff: 12 dBloctave

60,150.400.1 K92.5K.6K,1 5KHz.

+I

-

12dB nom, at each center freq.
Impedance: 100 ohms
Max. Sensitivity:

Max. Sensitivity:

3

volts nom. for full output.

500mv. nom. for full output

POWER

Output Power:

Frequency Response:
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:
Dimensions (W x H x D):

Due to our continuing efforts towards product improvement, the above specifications are subject to change
without notice.

AMPLIFIER

50 watts maximum per channel into 4 ohms. 18 watts per channel at less
than

1% THD. (14.0 volts D.C. Supply)
20Hz to 20KHz.

Mounting Brackets, Hardware, Installation instructions.
7"

x 1 " x 5-1 12"

178x25~ 141mm

+I-

3

dB at

1

watt.