MODEL 503BG
Unidirectional Dynamic Microphone
Developed for computer voice recognition applications,
the 503BG microphone offers excellent voice fidelity while
reducing background noise. Also use the 503BG in other
close-talking applications such as paging and talkback.
The 503BG features a low-impedance, moving coil type
transducer with an integral humbucking coil and an attached
two-conductor shielded cable with a built-in strain relief. It
produces a frequency response with an essentially constant
output voltage over the voice spectrum when used close to
the sound source.
The 503BG’s case is aluminum with a black enamel finish.
It mounts to a gooseneck, a fixed pipe or a microphone stand
using a standard 5/8”-27 thread. To secure the mounted
BG503, tighten the 4-40 screw with the supplied #4 Allen (hex-
head) wrench.
Features
S Optimized performance in voice processing and
computer voice recognition applications.
S Smooth frequency response with excellent fidelity
in the voice range.
S Cardioid pickup pattern and close-talking opera-
tion keep unwanted signals and background noise
at low levels.
S Constant output over voice spectrum when close
talked.
S Humbucking coil minimizes undesirable hum
effects such as CRT interference.
S Low-impedance design permits long cable runs in
extreme hum fields.
S Small unobtrusive design does not interfere with
CRT visibility.
S Rugged and reliable for years of consistent
operation.
SPECIFICATIONS
Type
Dynamic, unidirectional (cardioid), close-talking
Frequency Response
100 to 7,000 Hz (Figure 1)
TYPICAL FREQUENCY RESPONSE
FIGURE 1
Impedance
170 ohms actual
Output Level (Open Circuit Voltage)
–61.5 dBV/Pa (.84mV)*
–41.5 dB (8.4 mV)**
*1 Pa = 94 dBSPL
**0 dB = 1V/100 µbar
Polarity
Positive pressure on diaphragm produces positive voltage
on white conductor with respect to black conductor (Figure 2)
INTERNAL CONNECTIONS
FIGURE 2
Hum Pickup
Maximum 15 dB equivalent SPL in m0e field
Cable
1.2 m (4 ft) two-conductor shielded
Case
Aluminum with black enamel finish; stainless steel
screen.
Model 503BG User Guide
27C8091 (Rev. 7)
2007 Shure Incorporated
Printed in U.S.A
1 cm*
5 cm*
dB
Hz
* distance from speaker to microphone grille