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FLAT-PAK™ SERIES
Model FP-PA20
20 W Audio Power Amplifier
20 Watts RMS Audio Power Amplifier
Output for 8 Ohm Speaker
Maximized Audio Level at Full Power Output
Superior Audio Quality at High Output Levels
Input / Output Terminal Block Connections
Line Level Balanced or Unbalanced Input
Integral Audio Compressor to Control Clipping
High Overall Audio Operating Level
Peak LED to Indicate Audio Compression
Ultra-compact All Metal Construction
Convenience of RDL FLAT-PAKs
The FP-PA20 is part of the group of versatile FLAT-PAK products from Radio Design Labs. The unique
FLAT-PAK case can be directly screwed or bolted to cabinets or shelves. Optionally available rackmounting accessories permit single or multiple FLAT-PAK module mounting.
APPLICATION: The FP-PA20 is the ideal choice in many applications where a high quality utility amplifier
is needed to drive an 8 speaker.
The FP-PA20 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. The output will drive
an 8 speaker or multiple speakers connected to present an 8 load to the amplifier.
A red PEAK LED is provided to indicate the threshold of the integral compressor. Audio levels that could
cause the amplified output to clip are compressed according to two dynamic time constants. 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 compressor is
designed to remain aurally transparent while maintaining clean, unclipped amplified audio for input
overloads of up to 20 dB. The FP-PA20 produces average audio levels and audio clarity normally
expected of amplifiers delivering much higher output power.
The durable construction and low profile of the FP-PA20 allow mounting in a wide range of locations not
suited to a conventional style power amplifier. Power is provided to the module either through the barrier
block or through the DC power jack. For full RMS output power, a 24 VDC 2A power supply is required. A
1A supply is sufficient for normal program audio levels and content. Power supplies are sold separately.
Wherever a high quality 8 Ohm audio power amplifier is needed to provide reliability, compactness and
unsurpassed versatility, the FP-PA20 is the ideal choice.
other RDL products as part of a complete audio/video system.
Use the FP-PA20 individually, or combine it with
RDL 659 6th St. Prescott, AZ., USA 86301 (928) 443-9391 FAX (928) 443-9392 www.rdlnet.com
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FLAT-PAK
™
SERIES
Model FP-PA20
20 W Audio Power Amplifier
Installation/Operation
Declaration of Conformity available from rdlnet.com.
Sole EMC specifications provided on product package.
Specifications are subject to change without notice.
TYPICAL PERFORMANCE
Input: Line level
(+4 dBu nominal balanced)
(-10 dBV nominal unbalanced)
Input Impedance: 20 k balanced bridging
10 k unbalanced
Input / Output Connectors: 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 dBu
Unbalanced: +15 dBV
Frequency Response: 35 Hz to 50 kHz (+/- 1.5 dB)*
THD+N: < 0.1% (@ 1 kHz)*
Compressor: Threshold 6 dB below rated output,
automatically adjusting attack and release times
Noise: <-80 dB (below 20 W RMS)
CMRR: > 55 dB (50 Hz to 120 Hz)
Output Power: 20 W RMS into 8
Ambient Operating Environment:
Power Requirement: 24 Vdc @ 1650 mA (for continuous RMS power output, Ground referenced)
24 to 33 Vdc @ 1000 mA (for normal program material with minimal compression, Ground referenced)
Indicators (2): Red LED: PEAK LED indicates compressor activity
Green LED: Power ON
*measured at compressor threshold level equaling 4 W RMS output power
Overall Dimensions: Height: 2.30 in. 5.85 cm
Width: 3.25 in. 8.26 cm
Length: 6.04 in. 15.30 cm
< 0.5% (50 Hz to 20 kHz)*
0° C to 30° C Maximum; 20° C Recommended
-10 dB
-20 dB
-30 dB
-40 dB
COMPRESSION
0 dB
-40 dB -20 dB 0 dB
INPUT SIGNAL
20 W
OUTPUT SIGNAL
891-2110H
Radio Design Labs Technical Support Centers
U.S.A. (800) 933-1780, (928) 778-3554; Fax: (928) 778-3506
Europe [NH Amsterdam] (++31) 20-6238 983; Fax: (++31) 20-6225-287