5
Power Requirements
This microphone requires phantom power and performs best with a 48 Vdc supply (IEC-61938). However, it will
operate with slightly decreased headroom and sensitivity with supplies as low as 11 Vdc.
Most modern mixers provide phantom power. You must use a
balanced
microphone cable: XLR-to-XLR or
XLR-to-TRS.
Mounting the Microphone
Use the supplied microphone mount with floor or boom stands. Visit www.shure.com for more mounting options:
• To reduce the pickup of unwanted low-frequency mechanical vibrations, use an isolating shock mount.
• For stereo applications, use the optional Shure A27M Stereo Microphone Adapter.
Selecting Low-Frequency Response
A three-position switch on the back of the microphone lets you adjust
the low-frequency response. Use the low-frequency filter to reduce
wind noise, room noise, or proximity effect.
Flat response.
Provides the most natural sound in most
applications.
Low frequency cutoff.
Provides an 18 dB-per-octave cutoff at 80
Hz. Helps eliminate floor rumble and low-frequency room noise from
heating and air conditioning systems. This setting may also be used
to compensate for proximity effect or to reduce low frequencies that
make an instrument sound dull or muddy.
Low frequency rolloff.
Provides a 6 dB-per-octave rolloff filter
at 115 Hz. Use this to compensate for proximity effect or to reduce low frequencies that could make an instrument
sound dull or muddy.
Setting Attenuation
The attenuation switch lets you reduce the signal level without altering the frequency response. This can prevent ex-
tremely loud sounds from overloading the microphone circuitry.
0 dB
For "quiet" to "normal" sound levels.
−15 dB
For use with extremely loud sound sources such as drums, horns, or loud guitar cabinets.
−25 dB
For use with in close proximity (less than 10 cm) to extremely loud sound sources such as drums, horns, or
loud guitar cabinets.
20
1000
50
100
9
8
7
6
5
4
3
2
+5
0
–10
Hz
dB
Flat Response
Low Frequency Cutoff
Low Frequency Rolloff
Load Impedance
Maximum SPL capability, output clipping level, and dynamic range vary with the input load impedance of the pream-
plifier to which you connect the microphone. Shure recommends a minimum input load impedance of 1000 Ω. Most
modern microphone preamplifiers meet this requirement. Higher impedance results in better performance for these
specifications.
