Audio Technica PRO 31QTR Specifications

PRO 31QTR CARDIOID DYNAMIC MICROPHONE

•Designed for close-up vocal use

•Silent on-off operation thanks to MagnaLock™ switch design

•Hi-ENERGY® neodymium magnet for improved output and transient response

•Two-stage ball-type screen reduces wind noise and “popping” during close use

•Corrosion-resistant contacts from gold-plated XLRM-type connectors

•Rugged design and construction for reliable performance

•Cardioid polar pattern reduces pickup of sounds from the sides and rear, improving isolation of desired sound source

Output from the microphone’s XLRM-type connector is low impedance (Lo-Z) balanced. The signal appears across Pins 2 and 3; Pin 1 is ground (shield). Output phase is “Pin 2 hot” – positive acoustic pressure produces positive voltage at Pin 2.

When using the PRO 31QTR in settings with a stage monitor speaker, the speaker should be located 180° off axis (at the rear of the microphone). This placement, in conjunction with the microphone’s uniform cardioid pickup pattern, will virtually eliminate the possibility of undesired audio feedback.

The PRO 31QTR utilizes a MagnaLock on/off switch. This specially designed switch operates silently and may be locked in the “on” position to prevent accidental turn-off during use. To lock, slide the switch up into the “on” position (Fig. 1a). Using a small flat-head screwdriver, rotate the small screw in the center of the switch 90 degrees (1/4 turn) counter-clockwise (Fig. 1b). Never force the screw. When the screw slot position is horizontal (“across” the microphone body), the switch is locked. To unlock the switch, turn the screw 90 degrees clockwise until the screw slot position is again vertical (in line with the microphone body). Never try to turn the switch more than 90 degrees or 1/4 rotation. The switch may only be locked in the “on” position. Do not try to turn the screw when the switch is in the “off” position.

Take care to keep foreign particles from entering the windscreen. An accumulation of iron or steel filings on the diaphragm, and/or foreign material in the windscreen’s mesh surface, can degrade performance.

PRO 31QTR SPECIFICATIONS†

ELEMENT	Dynamic
POLAR PATTERN	Cardioid

FREQUENCY RESPONSE	60-13,000 Hz

OPEN CIRCUIT SENSITIVITY	–55 dB (1.7 mV) re 1V at 1 Pa*

IMPEDANCE	600 ohms

SWITCH	MagnaLock™ on/off
WEIGHT (less cable and accessories)	11.0 oz (312 g)

DIMENSIONS	7.28" (185.0 mm) long,
	2.09" (53.1 mm) head diameter

OUTPUT CONNECTOR	Integral 3-pin XLRM-type

CABLE	15.0' (4.5 m) cable with XLRF-type
	connector at microphone end,
	1/4" connector at equipment end

ACCESSORIES FURNISHED	AT8470 Quiet-Flex™ stand clamp for
	5/8"-27 threaded stands;
	5/8"-27 to 3/8"-16 threaded adapter;
	soft protective pouch

†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 Specifications are subject to change without notice.

Polar Pattern Frequency Response

330	30
300	60
										<![if ! IE]> <![endif]>in dB
									10 dB	<![if ! IE]> <![endif]>Response
270	90
240	120
	50	100	200	500	1k	2k	5k	10k	20k

210	150		Frequency in Hertz
			Frequency in Hertz
	180	LEGEND
SCALE IS 5 DECIBELS PER DIVISION		LEGEND	12" or more on axis

LEGEND

200 Hz

1 kHz

5 kHz

8 kHz

			Do not try
		Do not turn	to lock switch
Unlocked	Locked	screw clockwise	in the “off ”
Position	Position	to lock	position
			OFF
O N	O N	O N
Fig. 1a	Fig. 1b	Fig.1c	Fig. 1d

Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, Ohio 44224 Audio-Technica Limited, Old Lane, Leeds LS11 8AG England www.audio-technica.com