The Shure Beta 181 is an ultra-compact, side-address, condenser microphone, designed for discreet placement in live and studio environments. Featuring interchangeable cardioid, supercardioid, omnidirectional and bidirectional capsules for superior versatility, the small diaphragm of the Beta 181 provides superior audio with consistent, “textbook” polar responses in a form factor small enough to get close to the source in the tightest conditions.
The front of the microphone is marked by the Shure logo. Position this side toward the sound source.
The following table lists the most common applications and placement techniques. Keep in mind that microphone technique is largely a matter of personal taste; there is no one "correct" microphone position.
Cardioid | Supercardioid | Omnidirectional | Bidirectional |
---|---|---|---|
|
|
|
|
As with all bidirectional microphones, sounds picked up from the back will be out of polarity with the source. Those from the front are in polarity with the source.
Directional microphones are most sensitive to sounds arriving on axis and reject at angles depending upon the polar pattern. The following chart shows the rejection angles of each microphone. In live performance or recording settings, align monitors, P.A. loudspeakers, and unwanted sound sources at these angles.
To minimize feedback and ensure optimum rejection of unwanted sound, always test microphone placement before a performance.
Cardioid | Supercardioid | Bidirectional |
---|---|---|
|
|
|
Off-axis null points at 180 degrees | Off-axis null points at 120 degrees | Off-axis null points at 90 degrees |
Follow these steps to change Beta 181 capsules:
NOTE: Before each use, make surethe capsule is tightly secured on the micropgone, as vibration and accidental hits with drumsticks may loosen it, resulting in signal loss.
Maximum SPL capability, output clipping level, and dynamic range vary with the input load impedance of the preamplifier 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.
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.
Electret Condenser
181/C | Cardioid |
181/S | Supercardioid |
181/O | Omnidirectional |
181/BI | Bidirectional |
20 to 20,000 Hz
110 Ω
open circuit voltage, @ 1 kHz, typical
Cardioid | –46.5 dBV/Pa[1] (4.7 mV) |
Supercardioid | –49.5 dBV/Pa[1] (3.4 mV) |
Omnidirectional | –52.0 dBV/Pa[1] (2.5 mV) |
Bidirectional | –51.0 dBV/Pa[1] (2.8 mV) |
1 kHz at 1% THD[2]
2500 Ω load | Cardioid | 151.5 dB SPL |
Supercardioid | 154.5 dB SPL | |
Omnidirectional | 157.0 dB SPL | |
Bidirectional | 156.0 dB SPL | |
1000 Ω load | Cardioid | 149.0 dB SPL |
Supercardioid | 152.0 dB SPL | |
Omnidirectional | 154.0 dB SPL | |
Bidirectional | 153.5 dB SPL |
Cardioid | 73.5 dB |
Supercardioid | 71.5 dB |
Omnidirectional | 70.5 dB |
Bidirectional | 71.0 dB |
2500 Ω load | Cardioid | 131.0 dB |
Supercardioid | 132.0 dB | |
Omnidirectional | 133.5 dB | |
Bidirectional | 133.0 dB | |
1000 Ω load | Cardioid | 128.5 dB |
Supercardioid | 129.5 dB | |
Omnidirectional | 130.5 dB | |
Bidirectional | 130.5 dB |
@ 1 kHz, 1% THD
2500 Ω load | 10.5 dBV |
1000 Ω load | 7.5 dBV |
equivalent SPL, A-weighted, typical
Cardioid | 20.5 dB SPL-A |
Supercardioid | 22.5 dB SPL-A |
Omnidirectional | 23.5 dB SPL-A |
Bidirectional | 23.0 dB SPL-A |
20 to 20,000 kHz
≥55 dB
Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
11–52 V DC[4] phantom power (IEC-61938) 2.4 mA, maximum
145 g (5.1 oz.)
[1] 1 Pa=94 dB SPL
[2]THD of microphone preamplifier when applied input signal level is equivalent to cartridge output at specified SPL
[3]S/N ratio is the difference between 94 dB SPL and equivalent SPL of self noise, A-weighted
[4]All specifications measured with a 48 Vdc phantom power supply. The microphone operates at lower voltages, but with slightly decreased headroom and sensitivity.
Overall Dimensions
Beta 181/C
Beta 181/S
Beta 181/O
Beta 181/BI
Microphone Clip for AMS26, Beta 181, KSM137, KSM141, MX412, MX418, MX412S, MX418S, MX412SE, MX418SE, SM62, SM63, SM63L, SM63LB, SM81, VP64, VP64A, VP64AL and standard microphone stands |
A57F |
Foam case assembly for BETA181 |
A181C |
Foam Windscreen for BETA181 |
A181WS |
Beta 181 Cardioid Capsule |
RPM181/C |
Beta 181 Supercardioid Capsule |
RPM181/S |
Beta 181 Bidirectional Capsule |
RPM181/BI |
Beta 181 Omnidirectional Capsule |
RPM181/O |
Beta 181 Preamplifier |
RPM181/PRE |
Universal Microphone Mount with Large and Small Clip Adapters and Universal Threaded Adapter Post |
A75M |
Isolation Mount/Swivel Adapter for KSM109, KSM137, KSM141, SM63, SM81, SM94 and VP64 |
A53M |
25 foot (7.5m) Triple-Flex® Microphone XLR Cable with Switchcraft connectors |
C25E |
This product meets the Essential Requirements of all relevant European directives and is eligible for CE marking.
The CE Declaration of Conformity can be obtained from: www.shure.com/europe/compliance
Authorized European representative:
Shure Europe GmbH
Headquarters Europe, Middle East & Africa
Department: EMEA Approval
Jakob-Dieffenbacher-Str. 12
75031 Eppingen, Germany
Phone: 49-7262-92 49 0
Fax: 49-7262-92 49 11 4
Email: info@shure.de