Versatile, single-channel, utility building blocks in the popular Radio Design Labs ‘Flat-Pak’ packaging, which will mount directly to surfaces or using a range of mounting options. Inputs are electronically balanced and both eight ohm and 70/100V line models are offered, both powered by external 24 volt supplies, solving many varied requirements in most audio engineering environments. All models feature a compressor, automatically adjusting to avoid clipping and maximise audible level from the power available.
FP-PA18
This mono power amplifier with automatic energy-saving sleep mode, offers 18W RMS into an eight ohm load. This Class-D amplifier offers a sleep delay that is programmable to Off/5/15/25mins by way of sunken rotary control on the side of the FP-PA18. A gain control is located next to the I/O terminal block and can be adjusted using a trimming screwdriver. A red LED indicates when the output is 3dB below the rated output and the compressor is employed. The compressor has automatic attack and release adjustment. A green LED illuminates when audio is detected and when the amplifier provides an ‘active open collector’ output. Finally, a blue LED illuminates when the FP-PA18 is powered from its external 24Vdc power supply. The same LED is ‘dimly illuminated’ when the sleep mode disables the amplifier.
Input: Nominally +4dBu / -10dBV, minimum (to cross compressor threshold) -18dBu / -20dBV, maximum +23dBu / +21dBV balanced / unbalanced. Compressor threshold: 3dB below rated output. CMRR: better than >45dB, 50Hz-3kHz. Response: 20Hz - 20kHz +/- 1dB*. Distortion: less than 0.5% at 20Hz - 20kHz respectively*, THD+N. Output: 18W RMS, 8ohms load. Power source: Dimensions: 82.6 x 76.2 x 29.2 (w x l x h) mm. (*at compressor threshold level equivalent to 12W RMS output power).
FP-PA20 offers an output of 20W RMS into an eight ohm load. 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, un-clipped amplified audio for input overloads of up to 20dB. Average audio levels and audio clarity result that are normally expected of amplifiers delivering much higher output power.
Built in a black extrusion, the amplifiers have gain control and LEDs for power and peak level. Connections are by detachable terminal block. A co-axial connector provides an alternative connection for the DC power input. For full RMS output power, a 24V DC power supply with 2 amp capacity is required. A 1 amp supply is sufficient for normal program audio levels and content. Order power supply separately.
Input: Nominally +4dBu / -10dBV, minimum (to cross compressor threshold) -26dBu / -28dBV, maximum +23dBu/+15dBV, 20kohms/10kohms, balanced/unbalanced. Compressor threshold: 6dB below rated output. CMRR: better than 55dB, 50Hz-120Hz. Response: 35Hz - 50kHz +/- 1.5dB*. Distortion: less than 0.1%, 0.5% at 1kHz and 50Hz - 20kHz respectively*, THD+N. Output: 20W RMS, 8ohms load. Power source: 24V DC, 2A, ground referenced, for continuous 20W RMS power output; 24-33V DC, 1A for normal programme material with minimal compression. Ambient: 0-30°C, (20°C recommended). Dimensions: 82.6 x 153 x 58.5 (w x l x h)mm. ( *at compressor threshold level equivalent to 4W RMS output power).
FP-PA20A offers an output of 20W RMS into 70V or 100V lines, highly applicable to local zones in multi-zone PA installations. It is essentially similar to the FP-PA20, but has three output terminals for common, 70V 100V.
Specification is the same as the FP-PA20, except for the following. Response: 50Hz-20kHz +/- 3dB*. Output: 20W RMS, 70V or 100V line load.
FP-PA35A has a output of 35W RMS into 25/70/100V line. The Class D amplification has a frequency response of 50Hz to 20kHz, a user-adjustable sleep mode with steps of 5, 15, or 25minutes delay, and compressor/limiter with digital limiting.
Input: Nominally +4dBu / -10dBV, 20kohms / 10kohms, balanced/unbalanced. Compressor threshold: 2dB below rated output. CMRR: better than 60dB, 50Hz-120Hz. Response: 50Hz - 20kHz +/- 3dB. Distortion: less than 0.5%, 0.5% at 1kHz and 50Hz - 20kHz respectively, THD+N. Output: 35W RMS. Power source: 100-240V AC, 50-60Hz. Dimensions: 82.6 x 153 x 71 (w x l x h)mm.