Altec 1432a manual

Page 1

ALTEC

1432A
Variable Q Active Filter

Stereo 31 Band 1/3 Octave Equalizer

KEY FEATURES

fir Variable Q filter set

* 31 bands of boost and cut

A' Select between 6 dB or 12 dB
of boost and cut

KEY SYSTEM SPECIFICATIONS

20, 25, 32, 40, 50, 63, 80,
100, 125, 160, 200, 250, 315,
400, 500, 630, 800, 1k,
1.25k, 1.6k, 2k, 2.5k, 3.]5k,
4k, 5k, 6.3K, 8k, 10k, 12.5k,
16k Hz, 20k Hz

Center Frequencies:

Maximum Boost/Cut: 112 dB
Operating Gain: 0 dB
Low-Cut Filter
Comer Frequency: 43 Hz
Frequency Response
at Unity Gain: 20 Hz ~ 20 kHz, 2 1 dB

(High-Pass Filter Disengaged)

Total Harmonic Distortion

at Unity Gain: < 0.01%
(20 Hz - 20 kHz, 0 dBu Output)

Noise at Unity Gain: < -85 dBu
(20 Hz - 20 kHz)
Maximum Input Level
at Unity Gain: + 20 dBu (7.75 Vrms)
Maximum Output Level: + 20 dBu (7.75 Vrms)
DESCRIPTION

The Altec Lansing 1432A Dual Channel Stereo
Val-Octave Graphic Equalizer is a boost and cut
equalizer whose primary use is for tuning the
overall frequency response of a sound reinforce-
ment system, both to increase gain-be fore-feedback
and to compensate for the deficiencies in the
acoustic environment and the sound system.

The active Q variable filter set utilized in the
1432A allows effective equalization with few pro-
blematic side effects. As Figure 2 illustrates, the
filter characteristics vary with the amount of boost
or cut used. At low control settings, the filter Q is
very wide. As the control is boosted or cut, the filter

Q narrows so that there is minimum interaction
between adjacent frequency bands. The filter
response is designed to affect a I/:4-octave range.

Each of the 31 I/:s-octave filters provide 12 dB of
boost or cut at [$0 frequencies 20 through 20,000
Hz. The faders have apositive detent in the center,
fiat-response position. The gain control also has a
center detent at unity gain.

A low-cut filter switch. with a 43 Hz comer
frequency and 18 dB per octave slope, is located
on the front panel. A range select switch allows
selection of either 6 dB or 12 dB of boost or cut.

Page 2

Input:

W:
Impedance:
Non-rial level:
Output:
Type:
Impedance:

load impedance:

Peak Indicator:

Available Gain:

High-Pass Filter:

Controls:

1432A Specifications (cont'd)

(Ref. 0 dBv = 0.775 Vrms)
Electronically balanced

44 k0 balanced

22 k0 unbalanced

0 dBv (0.775 Vrms)

(Ref. 0 dBm = 0.775 Vrms
across 600 Q)
Electronically balanced
120 0 balanced

60 O unbalanced

600 .0. or higher

Red LED + 14 dBu (6 dB
before clipping)

:GdBortIZdB

Switch selectable with
cutoff below 43 Hz and a
slope of 18 dB per octave.

o 3] center detent slide
controls at 'A-octave cen-
ter frequencies from 20
Hz to 20 kHz, selectable
: 6 dB or t 12 dB
boost/cut.

o LEVEL control with
center detent

O LO-CUT select switch

ORANGEifidBor: 12
dB select switch

Connectors:
Input:

Output:

AC Power:

Operating Temperature
Range:

Dimensions:

Height:

Width:

Depth:

Net Weight:

Enclosure:

Accessories:

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DJ. APR 9213::11

Figure 1
:12 dB Control Settings, Individually Set

O EQ-ON Equalizer ON
select switch

0 AC Power switch

0 Ground-Lift Switch

3 Terminal barrier strip
(balanced)
3 Terminal barrier strip
(balanced)

5, 230 Vac 50/60 Hz
18 Watts

Up to 50° C (122" F)

3.46 inches (88 mm)
19.0 inches (483 mm)
9.24 inches (235 mm)

8.8 lbs (4.0 kg)

Rack Mount Chassis (l 3/4
inch rack space)

(included)

Power cord, mounting
screws, rubber feet, decal
and fuse for 230 Vac line
operation, 1432A installa-
tion and Operating Instruc-
tions