{"product_id":"redback-public-address-amplifier-pa-250w-4-input","title":"Redback Public Address Amplifier (PA) 250W 4 Input","description":"The Redback A 4387A 250 Watt 4 channel mixer amplifier is specifically designed for applications requiring up to three microphone inputs, without compromising output power and overall performance. The amplifier features three inputs which can be configured for either microphone or line level operation. Dimensions: ≈483W x 300D x 88H. \u003cbr\u003e \u003cbr\u003eThe A 4377A (see related below) conservatively delivers 125W RMS power, while the A 4387A delivers 250W RMS. Frequency response extends from 50Hz to 15kHz ±3dB at a total harmonic distortion (THD) of less than 0.5% @ 1kHz.  \u003cbr\u003e \u003cbr\u003eVox muting is provided on inputs one and two, which, when activated, automatically mutes the other inputs. Bass and treble controls and phantom powering capability enable unparalleled flexibility for a wide scope of applications such as factories, workshops, mine sites, sports clubs and office buildings.  \u003cbr\u003e \u003cbr\u003eThe amplifiers operate from 240V AC mains or 24V DC permitting battery backup operation during mains power failure. The output comes standard suitable for a 100V line load, but this can be configured internally to 70V line or low impedance (4 - 16Ω) loads.  \u003cbr\u003e \u003cbr\u003eThermal overload, overcurrent and overload protection circuitry and fuses on both AC and DC provide excellent fault condition protection and robust performance. The amplifier also utilises a half power mode which enables the amplifier to continue to run at a reduced output level if it is being over driven. \u003cbr\u003e \u003cbr\u003eTape output sockets are provided for recording purposes or feeding into additional power amplifiers.  \u003cbr\u003e \u003cbr\u003eRemote volume available when A 4373 Digital volume control module fitted internally and external A 2280B wall plate or 1KΩ potentiometer connected. \u003cbr\u003e \u003cbr\u003eAlert and Evacuation tones (conforming to AS1607.4) along with chime tones and voice over message option available when optional A 4573 fitted.\u003cbr\u003e\u003cbr\u003e\u003ch4\u003eFeatures\u003c\/h4\u003e\u003cul class=\"productfeatures\"\u003e \u003cli\u003e3 Balanced microphone inputs \/ 3 Aux inputs \/ 1 Music input \u003c\/li\u003e\n\u003cli\u003eRobust design incorporating latest Mosfet technology \u003c\/li\u003e\n\u003cli\u003eVery Low noise and distortion  \u003c\/li\u003e\n\u003cli\u003e100V standard with optional 70V and 4-16Ω outputs \u003c\/li\u003e\n\u003cli\u003e240V AC or 24V DC operation \u003c\/li\u003e\n\u003cli\u003eVOX muting on inputs 1 and 2 (Switch selectable internally) \u003c\/li\u003e\n\u003cli\u003eAdjustable VOX level sensitivities \u003c\/li\u003e\n\u003cli\u003eBass and Treble controls \u003c\/li\u003e\n\u003cli\u003eTape Output \u003c\/li\u003e\n\u003cli\u003ePhantom power on microphone inputs (DIP switch selectable internally) \u003c\/li\u003e\n\u003cli\u003eMulti stage thermally cued fan cooling \u003c\/li\u003e\n\u003cli\u003eOutput Peak Limited \u003c\/li\u003e\n\u003cli\u003eThermal Overload protected \u003c\/li\u003e\n\u003cli\u003eSignal Presence Indicator \u003c\/li\u003e\n\u003cli\u003eHalf power mode when overdriven \u003c\/li\u003e\n\u003cli\u003eFault Indicators \u003c\/li\u003e\n\u003cli\u003e24V DC Power Status Indicator \u003c\/li\u003e\n\u003cli\u003eOptional Alert\/Evac module with voice over message for emergency tones (A 4573) \u003c\/li\u003e\n\u003cli\u003eOptional remote volume (With A 4373 Digital volume control module fitted and external A 2280B wall plate) \u003c\/li\u003e\n\u003cli\u003eRack Mountable (suits 19 inch racks) with optional A 4376 rack ears\u003c\/li\u003e\n\u003c\/ul\u003e     \u003cp\u003e\u003ca href=\"#\"\u003e \u003cbr\u003e\u003cimg align=\"left\" style=\"border: 0px; background: none; margin-top: 0px; margin-bottom:0px; padding-right: 20px;\" src=\"https:\/\/images.altronics.com.au\/interface\/aust-made-sml.png\"\u003e\u003c\/a\u003e\u003cb\u003e100% developed, designed \u0026amp; assembled in Australia.\u003c\/b\u003e \u003cbr\u003eSince 1976 Redback PA products have been manufactured in Perth, Western Australia by Altronics. With over 40 years experience in the commercial audio industry, we offer consultants, installers and end users reliable products of high build quality with local product support.  \u003cbr\u003e    \u003c\/p\u003e\u003cp\u003e\u003ca href=\"#\"\u003e \u003cbr\u003e\u003cimg align=\"left\" style=\"border: 0px; background: none; margin-top: 0px; margin-bottom:0px; padding-right: 20px;\" src=\"https:\/\/images.altronics.com.au\/interface\/10-year-warranty.png\"\u003e\u003c\/a\u003e\u003cb\u003eBacked by an industry leading 10 Year Manufacturer Warranty.\u003c\/b\u003e \u003cbr\u003eOur Redback products have a long tried and tested history of bulletproof reliability.  Altronics offers a 10 Year Warranty on all Australian Made Redback products. Our local in-house service department has all the know how to answer technical queries and provide timely service. \u003cbr\u003e\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e \u003cli\u003e\n\u003cb\u003ePower Outputs\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003ePower: 250 watts RMS \u003c\/li\u003e \u003cli\u003eDistortion: \u0026lt; 0.5%, @ 1kHz  \u003c\/li\u003e \u003cli\u003eOutput line: 100V   \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eFrequency Response\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003eMic inputs : 50Hz - 12kHz, -3dB  \u003c\/li\u003e \u003cli\u003eLine inputs: 50Hz - 15kHz, -3dB  \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eMic Sensitivity\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003eMic inputs: 3mV  \u003c\/li\u003e \u003cli\u003eLine inputs: 1V \u003c\/li\u003e \u003cli\u003eMusic input: 500mV \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eSignal To Noise Ratio\u003c\/b\u003e  \u003c\/li\u003e \u003cli\u003eMic inputs: \u0026gt; 75dB below rated output  \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eLine Output\u003c\/b\u003e600Ω balanced, 0dB , 3 Pin XLR \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eOutput Connectors\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003eSpeakers: Screw terminals  \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eInput Connectors\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003eInputs: 3 pin XLR balanced or 2 x RCA  \u003c\/li\u003e \u003cli\u003e24V DC power: Screw terminals  \u003c\/li\u003e \u003cli\u003e240V AC power: IEC power connector  \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eMuting\u003c\/b\u003ePTT via microphone switch contacts and VOX muting (inputs 1-2)  \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eControls\u003c\/b\u003e  \u003c\/li\u003e \u003cli\u003eMic\/Line\/Music inputs: Volume  \u003c\/li\u003e \u003cli\u003ePower: On\/off switch  \u003c\/li\u003e \u003cli\u003eIndicators: Power, signal present, output peak limiting, over-temp , overload protect, half power, 24V DC \u003c\/li\u003e \u003cli\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cb\u003eGeneral\u003c\/b\u003e \u003c\/li\u003e \u003cli\u003ePower Supply: 240V AC or 24V DC \u003c\/li\u003e \u003cli\u003eFuse Protection: 250W - 7.5A AC ,20A DC \u003c\/li\u003e \u003cli\u003eDimensions: ≈483W x 300D x 88H \u003c\/li\u003e \u003cli\u003eWeight: ≈ 15.5kg \u003c\/li\u003e \u003cli\u003eCurrent Draw:  Min ≈ 350 mA, Max ≈ 20A\u003c\/li\u003e \u003c\/ul\u003e \u003cp class=\"footnote\"\u003e*Specifications are subject to change without notice.\u003c\/p\u003e\u003ch3\u003eDownloads\u003c\/h3\u003e\u003ca class=\"btn btn-info\" href=\"https:\/\/download.altronics.com.au\/files\/instructions_A4377A.pdf\" target=\"_blank\"\u003eInstructions\u003c\/a\u003e\u003cbr\u003e\u003ca class=\"btn btn-info\" href=\"https:\/\/download.altronics.com.au\/files\/brochures_A4387A.pdf\" target=\"_blank\"\u003eBrochure\u003c\/a\u003e","brand":"Redback","offers":[{"title":"Default Title","offer_id":53608812314897,"sku":"ALT-A4387A","price":1294.95,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0786\/7786\/8817\/files\/ALT-A4387A.jpg?v=1780110716","url":"https:\/\/www.teachersuperstore.com.au\/products\/redback-public-address-amplifier-pa-250w-4-input","provider":"Teacher Superstore","version":"1.0","type":"link"}