The STA-2A is a dual-channel, line-level audio preamplifier. Each channel is identical. The audio inputs are bridged at 20 kΩ and accept either an unbalanced or a balanced audio signal. Gain is adjustable from unity to +24 dB using a 25-turn precision audio taper trimming potentiometer. The output line driver circuits are designed to drive long balanced audio lines into 600 Ω loads.
The STA-2A features wideband circuitry for excellent phase response, low noise, low distortion and exceptional audio clarity. RDL's SupplyFlex power input configuration is included in the STA-2A. The power supply input may be fed from a floating (not ground-referenced) 24 Vdc power source, from a bipolar power supply (+/- 12 Vdc or +/-15 Vdc) or from a ground-referenced 24 Vdc power supply.
Many audio products provide optimum performance when feeding into a bridging input, but may not provide the output needed to directly drive low-impedance lines terminated with 600 Ω transformers. The STA-2A is specifically designed for such installations, and is also ideal in installations requiring high gain in line-level audio transmission.
Features:
- Up to 24 dB Gain in Audio Lines
- Conversion between Unbalanced and Balanced
- Conversion between High and Low Impedance
- Low-Impedance, High-Current Line Drivers
- Dual-Channel Line-Level Preamplifiers
- High Gain, High Output, High Performance
- RDL® SupplyFlex™ Power Input Configuration
Amps per STA-2A:
2 identical circuits (stereo or dual mono operation)
Inputs (2):
20 kΩ balanced or unbalanced
Input Signal (for +4 dBu out):
-20 dBu (-18 dBV) to +18 dBu
Maximum Input Level:
+24 dBu
Outputs (2):
150 Ω balanced or 75 Ω unbalanced
Output Signal:
Balanced:
+4 dBu nominal
Unbalanced:
6 dB below balanced line level
Maximum Output Level:
+25 dBu
Frequency Response:
10 Hz to 100 kHz (± 0.05 dB)
THD+N:
< 0.004% (unity gain)
IMD:
< 0.005% (unity gain)
Noise below +4 dBu:
< -90 dB (unity gain)
Crosstalk:
< -80 dB (unity gain)
Headroom:
> 20 dB (above +4 dBu)
Gain:
Unity +24 / -14 dB (adjustable)
CMRR:
> 60 dB (50 Hz to 120 Hz)
Ambient Operating Environment:
0° C to 55° C
Power Requirement:
GROUND-REFERENCED or FLOATING, 24 Vdc @ 50 mA
