Precision Audio and AV Interface Products

Radio Design Labs

FP-PA35A 35 W Mono Audio Amplifier - 25 V, 70 V or 100 V, with Power Supply

  • 35 Watts RMS Constant Voltage Amplifier
  • 25 V, 70 V or 100 V Output
  • Plenum Rated per UL 2043 Standard
  • Automatic Energy-Saving Sleep Mode
  • Selectable Sleep Delay: Off, 5, 15, 25 Minutes
  • Input / Output Terminal Block Connections
  • Line Level Balanced or Unbalanced Input
  • Compressor/Limiter Controls Clipping
  • LED to Indicate Audio Compression Threshold
  • Compressor Produces Maximized Average Output Power
  • Audio Quality Superior to Standard Amplifiers
  • Ultra-compact All Metal Construction
  • High-Efficiency Class D Operation
  • Thermal and Short-Circuit Protection
  • Overview
  • Specifications
  • Related Products
  • Accessories
  • Downloads
  • How to Buy
  • Product Series
  • Dimensions

The FP-PA35A is the ideal choice in many applications where multiple 25 V, 70 V or 100 V speakers in a zone need to be powered from a single audio power amplifier.

The FP-PA35A features a balanced line level input that may be connected unbalanced. A front panel gain control is designed to be adjusted manually or with a trimming screwdriver. The gain range will accommodate standard unbalanced levels as well as professional balanced levels. Multiple distributed sound system speakers connect to the corresponding 25 V, 70 V or 100 V amplified output.

The FP-PA35A includes an analog compressor/limiter for audio fidelity audibly superior to conventional class D amplifiers with digital limiting. The input GAIN setting determines whether the limiter alone is used for clipping suppression, or if the full compressor/limiter will be used to substantially increase the average output power beyond that of a standard 35 W amplifier. A red COMPRESSION LED flashes when the limiter is preventing output clipping. Normal audio level signals remain unaffected by the compressor thereby preserving audio dynamics. If the input level is increased so that the compressor is active, the LED remains dimly lit between peak flashes. The audio is compressed according to three dynamic time constants providing aural transparency while maintaining clean, unclipped amplified audio for input overloads of up to 20 dB. The FP-PA35A, with compression, is capable of producing average audio output levels and clarity normally expected from amplifiers with a much higher output power rating.

The FP-PA35A circuits are all designed for low power consumption. In the absence of an audio input, a digital timer is enabled to switch the class D output stage off. When this sleep mode is active, the amplifier module and its included RDL power supply consume less than 1 W of mains power. A front-panel control sets the sleep mode delay timer to 5, 15 or 25 minutes. The control also permits the installer to bypass the sleep mode to conform to system specifications that require the amplifier to be active at all times. Upon detection of an input signal, the amplifier is nearly inaudibly and instantly restored to full operation within 150 milliseconds.

A blue POWER LED illuminates when the FP-PA35A is powered from its external 24 Vdc power supply. The power LED is dimly illuminated when the sleep mode disables the amplifier and glows brightly when the amplifier operation is fully enabled. The module is equipped with both thermal and output short-circuit protection. The high-efficiency Class D output stage produces minimal heat for all levels of expected voice or music modulation. Continuous full-power operation with audio tones will not damage the amplifier, but is not recommended.

Applications

Input:
Line level (+4 dBu nominal balanced; -10 dBV nominal unbalanced)
Input Impedance:
20 kΩ balanced bridging; 10 kΩ unbalanced
Input / Output Connectors:
Detachable terminal block
Gain Adjustment:
Single turn audio taper
Minimum Input Levels:
Balanced: -14 dBu; Unbalanced: -15 dBV (to cross compressor threshold)
Maximum Input Levels:
Balanced: +22 dBu; Unbalanced: +20 dBV
Frequency Response:
50 Hz to 20 kHz (± 3 dB)
THD+N:
< 0.5% (1 kHz at compressor threshold); < 0.5% (50 Hz to 20 kHz, 1 W)
Compressor:
Threshold 2 dB below rated output, automatic adjusting attack and release times
Noise:
<-75 dB (below 35 W RMS)
CMRR:
> 60 dB (50 Hz to 120 Hz)
Output Power:
35 W RMS @ 25 V, 70 V or 100 V
Sleep Mode Power Consumption:
< 1 W (amplifier and included power supply)
Sleep Mode Delay:
5, 15 or 25 minutes (selectable)
Sleep Mode Disable:
Selectable
Active Mode Delay:
< 150 mS after input audio detected
Audio Detector Threshold:
-50 dBu balanced, -52 dBV unbalanced
Ambient Operating Environment:
0° C to 40° C Maximum; 20° C Recommended
Indicators (2):
Red LED: PEAK LED indicates compressor activity
Blue LED: Power ON, Dim: Sleep mode active; Bright: Amplifier active
Power Supply (included):
100 to 240 Vac, 50-60 Hz, 1.3 A, IEC C14; Output to module: 24 Vdc, 2 A, Ground-referenced
Plenum Rating Standard:
UL 2043
Dimensions:
Height: 2.80 in.(7.1 cm); Width: 3.25 in.(8.26 cm); Length: 6.04 in.(15.3 cm)
Package Type:
Cardboard Box
Package Dimensions:
8 x 6.5 x 3.25 in.
Shipping Weight:
3.34 lbs.
WEEE weight:
2.475 lbs.
Tariff code:
8543.70.9910

Documents:
Format
PDF
CAD Files:
Format
High Res Images:
Format
Press Release:
Format
Declaration of Conformity:
Format

Direct Dealer Program


Becoming an RDL direct dealer is quick and easy. To become a direct dealer, your company must meet the following requirements:

  • Must be an A/V contractor, sound contractor or system integrator

  • Must possess a current resale certificate for your state

Click here to submit a new direct dealer account inquiry.


Buy Online

FLAT-PAK SERIES

FLAT-PAK products are high performance application-specific A/V, recording and broadcast modules constructed in compact, low-profile, shielded heavy duty metal chassis'. Module functions include pre-amplification, format conversion, line driving, power amplification, mixing, distribution, equalization, level control and more. The unique FLAT-PAK case can be directly screwed or bolted to cabinets or shelves. Rack mounting accessories permit mounting single or multiple FLAT-PAKs to front or rear rails. Adjacent mounting of FLAT-PAK modules is facilitated by daisy-chaining multiple modules from a single power supply using included power interconnect cables.

FLAT-PAK modules provide the most common connections in professional installations, including gold-plated jacks, detachable and fixed terminal blocks. Bold, high contrast labeling facilitates connection and adjustment in confined or dark locations. LED metering and indicators shorten setup and adjustment time. Signal connectors and switches are very high quality. Circuits are designed for studio quality performance and are engineered for extended service life.

A FLAT-PAK module may be mounted right where its function is needed. Multiple FLAT-PAK and other RDL modules can be used together to form all or part of an A/V system that precisely matches users’ needs. The high performance of these modules and the continuity in product offering and support makes FLAT-PAK modules a preferred long-term resource for system design solutions. FLAT-PAK SERIES modules are designed and manufactured in the U.S.A.

FP-PA35A FP-PA35A