Crown LM-301A User manual

Crown International, Inc.
P. O. Box 1000
Elkhart, IN 46515-1000
TEL: [phone]
FAX: [phone]FAX
LM-301A
©2000 Crown International, Inc.
Specifications subject to change without prior notice.
Crown®is a registered trademark of Crown Interna-
tional, Inc.
5/00 125487-3
LM-301A Schematic
power. Make sure the phantom power switch
on the mic is on.
5.
If phantom power is not available on your au-
dio mixer, connect the mic cable from the LM-
301A to an external phantom power supply such
as a Crown PH-1A or PH-4B.
Connect another
mic cable between the phantom power supply
output and a mixer mic input.
6. If mechanical noise or breath pops are ex-
cessive, use a pen or pencil to set the flat/low-
cut switch in the electronics interface to “cut”
( ). Push the switch up to enable low cut.
7. Do not lubricate the gooseneck.
Architects’ and Engineers’ Specifications
The microphone shall be the Crown model
LM-301A or equivalent. The microphone shall
be a supercardioid electret-condenser type
with dual silent goosenecks. Electronics and
connector for the microphone shall be in a
separate rugged steel cylindrical housing. A
flat/low-cut switch shall be built into the elec-
tronics housing. A TA3F connector at the
end of the mic cable shall connect to the
electronics. The microphone shall have a
built-in 5/8-inch (15.88-mm)-27 threaded
collar that screws onto a mic stand, mic
boom or Atlas AD-12 male flange. The cable
can be routed either outside or inside the
mounting device.
The microphone shall be powered from 12
to 48 volts phantom powering. Frequency
response shall be uniform from 80 Hz to
15,000 Hz. Open-circuit sensitivity shall be
6 mV/Pa. Impedance shall be 150 ohms bal-
anced.
Maximum SPL capability shall be 120 dB SPL
at 3% THD. Equivalent noise shall be 28 dBA
typical (0 dB =.0002 dyne/cm2). The Crown
Model LM-301A microphone is specified.
Warranty
Crown professional microphones are guaran-
teed unconditionally against malfunction from
any cause for a period of three years from date
of original purchase. See enclosed warranty
sheet for additional information.
Service
If the microphone does not function properly,
replace or repair mic cables and connectors,
check the power supply.
If you determine the microphone product (s) is
defective, return the complete product (mic and
interface) in its original packaging to Crown
Service Department, Plant 2 SW, 1718 West
Mishawaka Road, Elkhart, IN 46517.For fur-
ther assistance or technical support call 800-
342-6939.
The mic and electronics are a matched pair.
Do not separate them. For service send them
both in.
Fig. 4WS-9 Foam Pop Filter
Fig. 3

Frequency Response
Polar Response
FRONT
REAR
-20
-15
-10
-5
-0
0˚ 30˚
60˚
90˚
120˚
150˚
180˚
210˚
240˚
270˚
300˚
330˚
400 Hz-7kHz
SUPERCARDIOID CONDENSER
DUAL GOOSENECK
LECTERN MICROPHONE
LM-301A
Specifications
Type: Unidirectional condenser.
Element: Electret condenser.
Frequency response (typical): 80 Hz to 15,000 Hz
(110 Hz to 15,000 Hz with low cut). See Fig. 1.
Polar pattern: Supercardioid. See Fig. 2.
Impedance: 150 ohms, balanced. Recommended
minimum load impedance 1000 ohms.
Open-circuit sensitivity: 6 mV/Pa* (–44.5 dB re
1 V/Pa*).
Power sensitivity: –42 dB re 1 mW/Pa*.
Equivalent noise level: 28 dB SPL typical
(0 dB=.0002 dyne/cm2), A-weighted.
S/N ratio: 66 dB at 94 dB SPL.
Maximum SPL: 120 dB SPL produces 3% THD.
Polarity: Positive pressure on the diaphragm
produces a positive voltage on pin 2 with respect
to pin 3 of the output connector.
Operating voltage: Phantom power, 12 to 48 volts
DC, positive voltage on pins 2 and 3 with respect
to pin 1 of the output connector.
Current drain: 3.5 mA.
Cable: 10' (3.05-m) 2-conductor shielded 0.1"
diameter cable integral to microphone terminated
with Switchcraft TA3F.
Connectors: Switchcraft TA3F on mic cable, TB3M
and 3-pin male XLR type in electronics interface.
Materials: Steel housing and gooseneck.
Finish: Black.
Weight: 5.5 ounces (159 grams).
Dimensions: See Fig. 3 on reverse side.
Included accessories: WS-9 foam pop filter (Fig. 4).
Optional accessories: WS-5 foam windscreen, LM-
301SMA shock mount adapter and windscreen.
PH-4B phantom power supply (4 channels,
AC powered), PH-1A phantom power supply
(1 channel, battery or AC adaptor powered),
PS-24 24V DC power supply for PH-1A.
*1 pascal = 10 microbars = 10 dynes/cm2= 94 dB
SPL.
Fig. 1
Frequency in Hz
Fig. 2
The Crown©LM-301A is a supercardioid,
electret condenser, miniature dual goose-
neck microphone. It is designed for pro-
fessional use on lecterns and for inconspicu-
ous miking of musical instruments. The
LM-301A comes in two parts: microphone/
cable and a cylindrical electronics housing.
The microphone has a built-in 5/8-inch (15.88-
mm)-27 threaded collar that can be screwed
onto a mic stand, mic boom or an Atlas AD-12
male flange. Because of the unique design of
the mounting collar, the mic cable can be
routed either outside or inside the mounting
collar.
Because of its supercardioid pickup pattern,
the LM-301A rejects more background noise,
room reverberation, and feedback than a typi-
cal cardioid microphone.
The LM-301A has a smooth, wide-range fre-
quency response for natural reproduction of
the singing or speaking voice. Very low fre-
quencies are filtered out to reduce pickup of
mechanically induced noise, room rumble, etc.
The gooseneck adjusts silently.
Supplied with the microphone is the WS-9, a
highly effective foam pop filter. Its two-stage
design greatly reduces explosive breath
sounds. A low-cut switch built into the elec-
tronics housing further reduces breath pops
and handling noise. Optional accessories in-
clude the LM-301SMA shock mount adapter.
The microphone output is a male 3-pin XLR-
type connector and is balanced, low imped-
ance, which allows long cable runs without
hum pickup or high-frequency loss. Superior
RFI protection is also provided.
Operating Instructions
Please refer to Fig. 3 to identify the parts men-
tioned.
1.
To route the mic cable inside the mounting
device:
remove the TA3F connector, push the
collar up onto the gooseneck and pull the
cable down through the collar. Reattach TA3F.
2. To route the mic cable outside the mounting
device:
remove the TA3F connector, push the
collar up onto the gooseneck, route the end of
the cable inside the collar and slot and pull the
cable up through the collar and slot. Reattach
TA3F.
3. Plug the electronics interface into a 3-pin
XLR-type cable routed to the audio mixer.
4. At the mixer, plug the mic cable from the
lectern into an input with 12-48 volt phantom
+15
+10
+5
dB 0
–5
–10
–15
–20
–25
–30
–35
20 100 1K 10K
LOW-CUT
0, 6"
FLAT
130, 2'