Radio Design Labs FP-PA20B

The FP-PA20B features a balanced line level input that may be connected unbalanced. A front panel gain control is designed to be adjusted either manually or with a trimming screwdriver. The gain range will accommodate standard unbalanced levels as well as professional balanced levels. A 25 V amplified output is provided to drive corresponding speakers in a distributed sound system. Audio levels that could cause the amplified output to clip are compressed using two dynamic time constants designed to preserve aural transparency. Normal audio level signals remain unaffected by the compressor thereby preserving audio dynamics and preventing the compressor from increasing feedback potential when the amplifier is used for paging. The FP-PA20B produces average audio levels and audio clarity normally expected of amplifiers delivering much higher output power.

Features:

• 20 Watts RMS Constant Voltage Amplifier
• 25 V Output
• Integral Audio Compressor to Control Clipping
• High Overall Operating Audio Level
• Maximized Audio Level for Output Power
• Audio Quality Superior to Standard Amplifiers

Specifications:

• Input: Line level (+4 dBu bal; -10 dBV unbal)
• Input Impedance: 20 kO balanced bridging; 10 kO unbal
• Input / Output Connector: Plug-in terminal block
• Gain Adjustment: Single turn audio taper
• Minimum Input Levels: Balanced:-26 dBu (to cross compressor threshold),Unbalanced: -28 dBV (to cross compressor threshold)
• Maximum Input Levels: Balanced:+23 dB, unbalanced: +15 dBV
• Frequency Response: 50 Hz to 18 kHz (+/- 3 dB)
• THD+N: < 0.1% (@ 1 kHz),< 0.5% (50 Hz to 20 kHz)
• Noise: < -80 dB (below 20 W RMS)
• Compressor: Threshold 6 dB below rated output, automatic adjusting attack and release
• CMRR: > 55 dB (50 Hz to 120 Hz)
• Output Power: 20 W RMS @ 25 V
• Ambient Operating Environment: 0° C to 30° C Max; 20° C Recommended
• Power Requirement: 24 Vdc @ 2000 mA, Ground referenced(for continuous RMSpower output), 24 to 33 Vdc @ 1000 mA, Ground referenced (for normaluncompressed audio)