Altec 1412a manual

Page 1

[\LIFEEC:

1412A
Variable Q Active Filter

Stereo 15 Band 2/2. Octave Equalizer

KEY FEATURES

* Variable Q filter set
wk 15 bands of boost and cut

KEY SYSTEM SPECIFICATIONS

25, 4o, 63, 100, 160, 250,
400, 630, 1k, 1.6K, 2.5x, 4k,
6.3k, 10k, 16k Hz

Center Frequencies:
Maximum Boost/Cut: :12 dB
Operating Gain: 0 dB

Low-Cut Filter
Comer Frequency: 43 Hz

Frequency Response
at Unity Gain: 20 Hz - 20 kHz, 1- 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
* Select between 6 dB 0" 12 dB (20 HZ . 20 kHz)
of boost and cut
Maximum Input Level
at Unity Gain: + 20 dBu (7.75 Vrms)
Maximum Output level: + 20 dBu (7.75 Vrms)
DESCRIPTION

The Altec Lansing 1412A is a boost and cut stereo
Ss-octave graphic equalizer whose primary use is
for tuning the overall frequency response of a
sound reinforcement system, both to increase gain-
before-feedback and to compensate for the deli-
ciencies in the acoustic environment and the sound
system.

The active Q variable filter set utilized in the
1412A allows effective equalization with few
problematic 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 interac-
tion between adjacent frequency bands. The filter
response is designed to affect a 2lsdoctave range.

Each of the 15 %-octave filters provide 12 dB of
boost or cut at [so frequencies 20 through 20,000
Hz. The faders have a positive detent in the center,
flat-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:

Typet

Impedance:
Normal level:
Output:

Twe:

Impedance:

Load Impedance:

Peak Indicator:

Available Gain:

High-Pass Filter:

Controls:

1 41 2A Specifications (contd)

(Ref. 0 dBv = 0.775 Vrms)
Electronically balanced

44 k0 balanced

22 k0 unbalanced

0 dBv (0,775 ers)

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

60 Q unbalanced

600 0. or higher

Red LED + 14 dBu (5 dB
before clipping)

:SdBor112dB

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

O 15 center detent slide
controls at 36-octave cen-
ter frequencies from 20
Hz to 20 kHz, selectable
4.- 6 dB or 1 12 dB
boost/cut.

O LEVEL control with
center detent

O LO-CUT select switch

ORANGE: 6dBor: I2
dB select switch

Connectors:
Input:

Output:

AC Power:

Operating Temperature
Range:

Dimensions:

Height:

Width:

Depth:

Net Weight:

Enclosure:

Accessories:

Figure
:12 dB Control Settings, Individually Set

l

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)

115, 230 Vac 50/60 Hz
18 Watts

Up to 50° C (122° F)

1.73 inches (44 mm)
19.0 inches (483 mm)
9.24 inches (235 mm)

6.0 lbs (2.7 kg)

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

(Included)

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