Altec 1905a manual

Page 1

ALTEC

1 905A
Variable Bandwidth

5 Band Parametric Equalizer

KEY FEATURES

*7 Five bands of equalization with

variable frequency range
* Variable bandwidth
* Variable low-pass and

high-pass filters

(20 Hz - 20 kHz, unweighted):

KEY SYSTEM SPECIFICATIONS

Frequency Ranges:
Coarse: 17 Hz - 130 Hz
170 Hz - 1.3 kHz
1.7 kHz - 13 kHz
Fine: 16.5 Hz - 205 Hz

165 Hz - 2.05 th
1.65 kHz - 20.56 kHz

Maximum Boost/Cut: +15/-25 dB

Bandwidth: Variable from

1/12 - 2 octaves

2.5 kHz - 30 kHz,
12 dB/octave

Low-Pass Filter:

High-Pass Filter: 15 Hz - 300 Hz,

12 dB/octave
Frequency Response: 20 Hz - 20 kHz, 11.5 dB
Distortion (@ +4 dBm): < 0.01 96 @ 1 kHz

Equivalent Input Noise
< -90 dBm

DESCRIPTION

The Altec Lansing 1905A is a boost and cut five
band Parametric Equalizerwhose 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 deficiencies in
the acoustic environment and the sound system.

The ability to control both the bandwidth and
center frequency of a bank of filters as well as the
degree of boost or cut opens up a new dimension
in equalization allowing filter correction and cre-
ative filtenng capabilities of unparalleled accuracy
and precision.

Each of the five parametric filters allows a
range from +15 dB of boost to -25 dB of cut at vari-
able frequencies per band.

A high-pass filter control, with a variable comer
frequency range of 15 Hz - 300 Hz and 12 dB per
octave slope, is located on the front panel along
with a low-pass filter control, with a variable comer
frequency range of 2.5 kHz - 30 kHz and 12 dB per
octave slope. A master level control allows the
signal to be boosted up to 6 dB or cut to -oo. A
master EQ-lN switch allows the user to remove the
equalizer from the signal path.

The 1905A can be used as a stand alone
parametric equalizer, or can be utilized in con-
junction vvith the TEF 20 and AcoustaEQ software.
This allows a higher degree of accuracy in the
equalization process.