Altec Lansing 1209B - Manual (Page 4)

ALTEC 1209B
ARCHITECT'S AND ENGINEER'S SPECIFICATIONS
The powered speaker system shall be the biamplified sound reinforcement type with
a sturdy %" plywood front-loaded LF exponential horn, a self-contained electronic
crossover biamplifier, a 15" musical instrument type LF loudspeaker, an HF driver
and a cast aluminum 25" sectoral HF horn having exponential expansion. A 50',
2-conductor cable with standard phone plug at each end shall be included with
the system.
The biamplifier shall contain a power supply capable of operating from a 120V ac,
50/60 Hz line, electronic crossover circuitry, separate LF and HF power amplifiers
and fail-safe protective circuitry for its output transistors. All circuitry in the bi­
amplifier shall be solid state, with ail transistors and diodes of the silicon type. The
biamplifier shall meet the following performance criteria. Amplifier outputs; 60
watts bass, 30 watts treble. THD at full rated output, less than 0.5% at all frequencies
from 20 Hz to 20 kHz. Input sensitivity for rated output; 0.5V rms direct or with
line-matching transformer accessory, 0.1V rms with line-bridging transformer acces­
sory. Input impedance; 15,000 ohms direct or with line-matching transformer acces­
sory, 600 ohms with line-bridging transformer accessory. Load impedance, 8 ohms
nominal for each amplifier. Bass amplifier gain with full boost; 52 dB with line­
matching transformer accessory, 66 dB with line-bridging transformer accessory.
Treble amplifier gain with full boost; 49 dB with line matching transformer acces­
sory, 63 dB with line-bridging transformer accessory. Crossover frequency; 500,
800 or 1500 Hz (selectable) with 12 dB/octave crossover slope. Each channel shall
have a separate slide-type gain control, continuously variable from -i-6 dB to -15 dB.
The speaker system shall meet the following performance criteria. Frequency
response, 35 Hz to 20 kHz (normalized composite output). Pressure sensitivity,
103 dB SPL when measured at 4' on axis with 1 watt input of pink noise from 100
Hz to 10 kHz (Ref.: 0.0002 dyne/cm^). Equivalent El A rating, 56 dB SPL when
measured at 30' on axis with 1 milliwatt input. Acoustic output for rated power at
maximum gain settings — with direct input or high-level, balanced-line matched
input; 118.0 dB SPL when measured at 4' on axis with 0.5V rms input of pink
noise from 500 Hz to 3000 Hz (Ref.: 0.0002 dyne/cm^); with high-level, balanced-
line bridging input; 118.0 dB SPL when measured at 4' on axis with 0.1V rms input
of pink noise from 500 Hz to 3000 Hz (Ref.: 0.0002 dyne/cm^). Crossover fre­
quency, 500 Hz with 12 dB/octave crossover slope. Horizontal distribution pattern,
uniform over 90°. Vertical distribution pattern, uniform over 40°. Dimensions;
54V4" H X 30" W X 24" D (HF horn externally mounted), 42" H x 30" W x 24" D
(HF horn internally mounted). The speaker system shall be finished in medium
gray enamel and shall weigh 180 pounds.
The speaker system shall be the ALTEC Model 1209B.
The 1209B shall be furnished with the following ALTEC accessories (select as
required and insert quantity):
.15095A Line Bridging Transformer_______15335 Line Matching Transformer
LITHO IN U.S.A. CP-273-5K
Specifications and components subject to change without
notice. Overall performance will he maintained or improved.
AL-1829
I