By removing an attached AT8533x power
module, the cable from the microphone can be
routed through the bottom of the flange instead
of exiting from the side as supplied (Fig. 1).
The provided foam windscreen simply slips
over the head of the microphone, effectively
reducing wind noise or “popping” when used
extra close.
The small-diameter gooseneck is easy to
manipulate for proper positioning. Heavily lubri-
cated, it operates smoothly and quietly. Should
the unit become noisy with prolonged use, apply
a light machine oil directly on the gooseneck
area affected.
While a modern condenser microphone is
not unduly sensitive to the environment, tempera-
ture 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.
AT915AMRx/C
Cardioid
Description
The AT915AMRx/C is a wide-range
condenser microphone with a cardioid polar
pattern. It is designed for quality sound reinforce-
ment, professional recording, television, and
other demanding sound pickup applications. The
small-diameter alternating gooseneck design
permits highly flexible positioning while maintain-
ing a smooth, well-contoured appearance. Its
adjustable-length design allows for the ultimate in
positioning flexibility. The AT915AMRx /C features
a
5
/
8
"-27 threaded flange that allows it to mate with
the threads of a standard microphone desk or floor
stand. A
5
/
8
"-27 threaded stud is also provided so
it can be secured to a permanent mounting surface.
The microphone features a 9.8' (3.0 m)
permanently-attached miniature cable. Its free end
connects to the provided AT8533x power module
via internal solderless screw terminals for simple
length adjustment in the field. It can be powered
from any external 9V to 52V DC phantom power
supply. A recessed switch in the power module
permits choice of flat response or low-frequency
roll-off to help control undesired ambient noise.
Four additional interchangeable elements
are available to permit selection of angle of
acceptance from 90
°
to 360
°
.
Audio-Technica design engineers have utilized
the newest low-mass diaphragm technology in the
quest for superior performance. The permanent
charge is now on the fixed back plate, rather than
the moving element. With A-T fixed-charge “back
plate” construction, a gold-vaporized diaphragm
just 2 microns thick (about .000079") can be used.
This considerably reduces moving mass, thus
improving frequency response and transient
response while reducing distortion.
The microphone is enclosed in a rugged
housing with a low-reflectance black finish.
Installation and Operation
Output is low impedance balanced. The
output connector of the power module mates with
XLRF-type cable connectors. The balanced 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 shorten the cable, remove the three
screws from the base of the power module and
slide the outer case up the cable to reveal the
circuit board and screw terminals. Loosen the
three terminal screws and remove the cable from
the module. Next, slide the case off the cable, cut
the cable to the desired length (allowing a few
extra inches) and slide the case back onto the
cable. Tie a single knot in the cable about two
inches from the cut end. Following Figure 2, cut
the cable off 1" down from the top of the knot and
carefully remove
1
/
2
" of the outer jacket. Strip the
mic cable wires and attach them to their respec-
tive terminals (Fig. 3). Make certain that the termi-
nals are clamped on the conductors, not on the
insulation, and that there are no loose strands of
wire which might touch other terminals. Replace
the case, being certain that it goes
over the case
grounding contact and that the roll-off switch is
accessible. Finish by replacing the three base
screws and testing for proper operation.
Frequency Response
(Typical)
LEGEND
Roll-off
12" or more on axis (flat)
Frequency in Hertz
Response in dB
10 dB
20k
10k
5k
2k
1k
500
200
100
50
Shield strands,
fully twisted
Yellow-Yellow
Red-Red
1
/
8
" strip reds
and yellows
1
/
2
"
1"
Terminal
screws
Case
grounding
contact
Yellow-Yellow
Red-Red
Shield
PC board
switch side
S
Y
R
Figure 3
Figure 2
Miniature
Condenser
Adjustable-
length
Gooseneck
Adapter-
mount
Microphone
Figure 1. Cable routing
