S p a - 3 – QSC Audio SPA-3 User Manual
Page 2
QSC Audio Products, Inc.
1675 MacArthur Boulevard
•
Costa Mesa, CA 92626
•
Ph: 800/854-4079 or 714/957-7100
•
Fax: 714/754-6174 • www.qscaudio.com
Specifications subject to change without notice.
S P A - 3 S P E C I F I C A T I O N S
GENERAL INFORMATION
Attenuation
PROGRAMMABLE OPERATING PARAMETERS
DataPort
0 to 32 dB in 0.5- or 1.0-dB increments
HD15 male (to amplifier); HD15 female (to QSControl system)
External power
Coaxial jack
Bypass, Mute, or Lock
Either channel
S P A - 3
Operating temperature
0–70° C
Input type, each channel
Differential balanced (transformer balancing optional)
Input impedance
28.4 k
ΩΩ balanced, 14.7 kΩΩ unbalanced
Output impedance, main
95
ΩΩ, quasi-balanced
+18 dBu
Noise (0 dBr = maximum output)
-116 dBr
THD @ +4 dBu out
<0.01% @ 1 kHz
Frequency response
20 Hz–20 kHz, ±0.2 dB
Common-mode rejection
>50 dB minimum; >60 dB typical
CONTROLS
Programming
Pushbutton switches for incremental programming: Shift, Up, and Down
INDICATORS
Attenuation (each channel)
2-digit 7-segment LED display
Signal presence (each channel)
Green LED
CONNECTORS
Input (two channels)
5-pin “Euro-style” detachable terminal block
+15V @ <300 mA, via external power jack, or from amplifier via pin 9 of DataPort
Power requirements
Maximum RMS output voltage
0.5 dB indicator (each channel)
Decimal point
Up
Down
Shift
½
Micro-
controller
8.8.
Digital
Potentio-
meter
2-Digit
7-Segment
Display
Input
Stage
Output
Stage
Signal
LED
To amplifier,
via DataPort
8.8. 8.8.
Block diagram of SPA-3 (one channel shown)
Mounting the SPA-3 to a two-channel
CX, DCA, or PL2 amplifier
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