Search Microphones

Share This Page

OmnidirectionalCardioidBidirectionalSupercardioidShure Beta 181

Detachable-Capsule Condenser Microphone

Shure’s Beta 181 is an innovative, compact microphone system with four compatible detachable capsules: Cardioid, Omni, Figure-of-8, and Supercardioid.

All four are small-diaphragm electret capsules. The capsules’ sensitivity lies in the range of 2.4–4.7 mV/Pa, which is lower than most studio condensers. The capsules’ self-noise ratings are over 20dBA, making the mic appear to be best suited to reproduction of relatively loud sources and/or stage environments where the noise floor is unlikely to be audible. In such applications, the benefit of lower sensitivity is that the mic can be used without a pad.

These characteristics, according to Shure, are entirely by design. As part of the Beta product line, the 181 was designed to be used on loud sources on stage, without a pad. The Beta 181 can withstand a max SPL over 150dB without clipping; this is unusual for a condenser microphone, but is an excellent tradeoff given its intended applications.

One of the unique features of the Beta 181 is its side-address form factor. This allows the mic to be hung by its cable over a guitar cabinet, or to be positioned just over the rim of a drum much more easily than an end-address design.

Another unique feature is the orientation pin on the capsule head. This ensures that the front of the capsule lines up with the logo on the head amp, making it easy to discern the front of the mic. (We have seen side-address microphones that are not so well labeled; in the pressure of a session setup, it is surprisingly easy to point such capsules away from the source.)

All four capsules show nominally flat frequency response from 50Hz to about 3kHz, and all but the Fig-8 show a broad presence peak of up to +7dB at 10kHz.

Polar pattern control is tight and consistent below 1000Hz for all capsules. Above 2500Hz, the patterns are frequency-dependent, suggesting that the mics’ off-axis response is somewhat colored at higher frequencies.

The Beta 181 is available in multiple configurations, including:

  • Beta 181/C - with RPM181/C Cardioid capsule
  • Beta 181/S - with RPM181/S Supercardioid capsule
  • Beta 181/O - with RPM181/O Omnidirectional capsule
  • Beta 181/BI - with RPM181/BI bidirectional (figure-of-8) capsule

Some sellers provide alternative packages, including deluxe stereo sets.

The mic ships with a single Beta 181 head amplifier (Shure p/n RPM181/PRE), one of the four capsules — Cardioid, Omni, Supercardioid, Figure-of-8 — plus a mic clip (p/n A57F), foam windscreen (p/n A181WS), and a zippered storage pouch (p/n A181C).

Tony SanFilippo, 2012

The Beta 181 on toms RULED!!!

The Shure Beta 181 is also known as: Beta 181/C, Beta 181/O, Beta 181/S, Beta 181/BI.

The mic was released in 2010.


Compatible Capsules
Shure RPM181/BIBidirectional Shure RPM181/BI
Bidirectional capsule
Sensitivity: 2.81 mV/Pa
Freq. Resp.: 20 - 20,000 Hz
MSRP: $311 | Still In Production
Shure RPM181/CCardioid Shure RPM181/C
Cardioid capsule
Sensitivity: 4.73 mV/Pa
Freq. Resp.: 20 - 20,000 Hz
MSRP: $311 | Still In Production
Shure RPM181/OOmnidirectional Shure RPM181/O
Omnidirectional capsule
Sensitivity: 2.5 mV/Pa
Freq. Resp.: 20 - 20,000 Hz
MSRP: $311 | Still In Production
Shure RPM181/SSupercardioid Shure RPM181/S
Supercardioid capsule
Sensitivity: 3.35 mV/Pa
Freq. Resp.: 20 - 20,000 Hz
MSRP: $311 | Still In Production
Pads & Filters Impedance SPL/Noise
n/a 110 Ohms (Low) Max SPL: 151 dB
Weight Length Max Diameter Interface(s)
145g (5.11oz) 124mm (4.88'') 20mm (0.79'')
  • 3-pin XLR male (1)
Power Specifications
  • Requires phantom power
  • Phantom voltage: 11–52v

Did we get anything wrong on this page? Please let us know!