PRO 31QTR CARDIOID DYNAMIC MICROPHONE
PRO 31QTR SPECIFICATIONS†
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
• 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
†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 /cm 2 = 10 microbars = 94 dB SPL
Specifications are subject to change without notice.
Frequency Response
Polar Pattern
• Corrosion-resistant contacts from gold-plated XLRM-type
connectors
0
330
30
300
60
• Rugged design and construction for reliable performance
10 dB
90
270
• Cardioid polar pattern reduces pickup of sounds from the sides
and rear, improving isolation of desired sound source
240
120
50
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.
210
150
100
500
200
1k
5k
2k
10k
20k
Frequency in Hertz
180
SCALE IS 5 DECIBELS PER DIVISION
LEGEND
D
12" or more on axis
s
LEGEND
200 Hz
1 kHz
5 kHz
8 kHz
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.
Unlocked
Position
Locked
Position
Do not turn
screw clockwise
to lock
Do not try
to lock switch
in the “off ”
position
OFF
ON
ON
ON
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
P3893-00181
P51678-EN
©2004 Audio-Technica U.S., Inc.
Printed in Taiwan
Response in dB
• Designed for close-up vocal use
ELEMENT