Audio Technica Engineered Sound AT845R Product Information

microphone with an omnidirectional polar pattern. It is designed for unobtrusive table, ceiling or panel-mounted applications for high-quality sound reinforcement, teleconferencing, profes- sional recording, television and other demanding sound pickup applications. The AT847R is a similar microphone, with a unidirectional polar pattern. Positioning a properly designed miniature unidirectional microphone centrally on a large, flat, unobstructed surface yields several distinct advantages. The directivity factor is greatly increased over a comparable omnidirectional microphone, thus promoting enhanced gain before feedback and further suppressing ambient noise. Sensitivity is increased for improved signal-to-noise ratio. Phase distortion due to reflected sound energy from the boundary itself is eliminated. Both microphones require 9V to 52V DC phantom power for operation. The microphones are enclosed in a heavy-duty die-cast case and protected by two layers of heavy perforated steel. The low-profile housing has a low-reflectance black finish. The microphones are also available in white, as AT845RW and AT847RW. Isolators are included with each microphone for applications where mechanical isolation from the mounting surface is required. Installation and Operation Output is low impedance balanced. The bal- anced signal appears across Pins 2 and 3, while the ground (shield) connection is Pin 1. Output is phased so that positive acoustic pressure produces positive voltage at Pin 2 in accordance with industry convention. To mount these microphones in a ceiling or table top without the isolators, a 13⁄16" diameter hole is required. To mount these microphones with the isolators, a 15⁄16" hole is required. The isolators can be placed on either side of the hole for mechanical isolation from the mounting surface. The Audio-Technica round mark ( ) on the AT847 bezel indicates the “front” of the microphone. While a modern fixed-charge condenser microphone is not unduly sensitive to the environ- ment, temperature extremes can be harmful. Exposure to high temperature can result in gradual and permanent reduction of the output level. Avoid leaving the microphone in the open sun or in areas where temperatures exceed 110° F (43° C) for long periods of time. Extremely high humidity should also be avoided. Architects and Engineers Specifications AT845R [AT845RW] The microphone shall be a fixed-charge condenser with an omnidirectional polar pattern designed for use in table, ceiling or panel-mount applications. The frequency response shall be 30 Hz to 20,000 Hz. The microphone shall operate from an external 9V to 52V phantom power source. Nominal open-circuit voltage shall be 7.9 mV at 1 kHz, 1 Pascal. Output shall be low impedance balanced (200 ohms). AT845R/RW Omnidirectional AT847R/RW Cardioid Condenser Boundary Microphones The microphone shall have a self-contained power module with an XLRM-type output connector. The microphone shall have a diameter of 1.10" (28.0 mm) and a length of 2.72" (69.0 mm). Weight shall be 2.1 oz (60 grams). The micro- phone shall be housed in a die-cast case with a two-layer perforated steel grille. Finish shall be low-reflectance black [white]. The Audio-Technica AT845R [AT845RW] is specified. AT847R [AT847RW] The microphone shall be a fixed-charge condenser with a unidirectional polar pattern designed for use in table-mount applications. The frequency response shall be 30 Hz to 20,000 Hz. The microphone shall operate from an external 9V to 52V phantom power source. Nominal open- circuit output voltage shall be 7.9 mV at 1 kHz, 1 Pascal. Output shall be low impedance balanced (200 ohms). The microphone shall have a self-contained power module with an XLRM-type output connector. The microphone shall have a maximum diameter of 1.18" (30.0 mm) and a length of 2.72" (69.0 mm). Weight shall be 2.2 oz (62 grams).The microphone shall be housed in a die-cast case with a two-layer perforated steel grille. Finish shall be low-reflectance black [white]. The Audio-Technica AT847R [AT847RW] is specified. Frequency in Hertz Response in dB 10 dB 20k 10k 5k 2k 1k 500 200 100 50 LEGEND 12" or more on axis AT847R Frequency Response AT845R Frequency Response Frequency in Hertz Response in dB 10 dB 20k 10k 5k 2k 1k 500 200 100 50 LEGEND 12" or more on axis

Audio-Technica Limited, Old Lane, Leeds LS11 8AG England One-Year Limited Warranty Audio-Technica microphones and accessories purchased in the U.S.A. are warranted for one year from date of purchase by Audio-Technica U.S., Inc. (A.T.U.S.) to be free of defects in materials and workmanship. In event of such defect, product will be repaired promptly without charge or, at our option, replaced with a new product of equal or superior value if delivered to A.T.U.S. or an Authorized Service Center, prepaid, together with the sales slip or other proof of purchase date. Prior approval from A.T.U.S. is required for return. This warranty excludes defects due to normal wear, abuse, shipping damage, or failure to use product in accordance with instructions. This warranty is void in the event of unauthorized repair or modification. For return approval and shipping information, contact the Service Department, Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, Ohio 44224. Except to the extent precluded by applicable state law, A.T.U.S. will have no liability for any consequential, incidental, or special damages; any warranty of merchantability or fitness for particular purpose expires when this warranty expires. This warranty gives you specific legal rights, and you may have other rights which vary from state to state. Outside the U.S.A., please contact your local dealer for warranty details. Form No. 0309-9200-02-B/W P50880 © 1996 Audio-Technica U.S., Inc. Printed in U.S.A. Element Fixed-charge back plate permanently polarized condenser Polar Pattern AT845R Omnidirectional AT847R Unidirectional (Cardioid in hemisphere above mounting surface) Frequency Response 30-20,000 Hz Open Circuit Sensitivity –42 dB (7.9 mV) re 1V at 1 Pa* Impedance 200 ohms Maximum Input Sound Level 142 dB SPL, 1 kHz at 1% T.H.D. Dynamic Range (Typical) AT845R 112 dB, 1 kHz at Max SPL AT847R 113 dB, 1 kHz at Max SPL Signal-to-noise Ratio1 AT845R 64 dB, 1 kHz at 1 Pa* AT847R 65 dB, 1 kHz at 1 Pa* Phantom Power Requirements 9-52V DC, 2 mA typical Weight AT845R 2.1 oz (60 grams) AT847R 2.2 oz (62 grams) Dimensions AT845R 1.10" (28.0 mm) dia, 2.72" (69.0 mm) length AT847R 1.18" (30.0 mm) dia, 2.72" (69.0 mm) length Output Connector Integral 3-pin XLRM-type Accessory Furnished One pair isolators † In the interest of standards development, A.T.U.S. offers full details on its test methods to other industry professionals on request. * 1 Pascal = 10 dynes/cm2 = 10 microbars = 94 dB SPL 1 Typical, A-weighted, using Audio Precision System One. AT845R, AT847R Specifications† 1 kHz 5 kHz 8 kHz LEGEND SCALE IS 5 DECIBELS PER DIVISION 90 60 120 30 150 210 240 270 300 330 180 0 100 Hz 1 kHz 5 kHz 8 kHz LEGEND SCALE IS 5 DECIBELS PER DIVISION 90 60 120 30 150 210 240 270 300 330 180 0 AT847R Polar Pattern AT847R Dimensions AT845R Polar Pattern AT845R/RW AT847R/RW FRONT OF MIC LOGO DESIGNATES 1.02" 26.0 mm 30.0 mm 1.18" ISOLATORS TABLE NUT 2.72" 69.0 mm 0.33" 8.5 mm 0.79" 20.0 mm ISOLATORS NUT 2.72" 69.0 mm 0.33" 8.5 mm 0.79" 20.0 mm 1.10" 28.0 mm CEILING AT845R Dimensions