Microphone Capsules

Measurement Microphone Capsules & Preamplifiers

Cirrus Research plc provides a range of measurement microphones, preamplifiers, power supplies and microphone accessories.

The Class+ Microphones are a range of high performance ½” Pre-polarised Electret condenser capsules designed for use on Sound Level Meters and Noise Measurement Equipment. The range also includes a wide range of accessories that enhance the performance of the Class+ Capsules.

All of the Class+ capsules are based on the same technology, with all of the capsules being mechanically compatible.

At the top of the range, the MK:224 capsule is fitted to several leading brands of Sound Level Meters as well as PC based instruments and Noise Monitoring Systems. In many applications, the use of the most accurate microphone capsule is excessive, and a lower specification can be accepted. In these situations, the Class+ microphone capsules are ideal replacements for existing units at significantly lower cost, often less than 50% of competing units in OEM applications.

The MK:224 is the most accurate and stable of the Class+ Microphone capsules and is used on the Cirrus Research plc Class 1 Sound Level Meters, Noise Analysers and Noise Monitoring Systems. The excellent long term stability and temperature stability allow the capsule to be used in long term outdoor monitoring applications, and has been in use in Cirrus Research plc Airport Noise Monitoring systems over periods of many years.

The MK:216 is the Class 2 variant of the MK:224 and is fitted as standard to the Class 2 Optimus sound level meters

MV:220A 1/2” Prepolarised Microphone Preamplifier

The MV:220A 1/2-inch Preamplifier is a general purpose preamplifier suitable for use with prepolarised microphone capsules.

It is a small unit with a slimline profile and is powered via the coaxial BNC-type connector. Power is from a suitable constant-current source of typically 4mA with a power supply excitation voltage of between 15v and 24v DC.

The frequency response (-3dB points) of the MV:220A are 2.6Hz to 150kHz.

The MV:220A can be used with the Cirrus Research Class+ Microphone Capsules including:

  • MK:224 Class 1 Microphone Capsule
  • MK:216 Class 2 Microphone Capsule

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Microphone Caspule Features

  • Pre-polarised Electret Condenser Technology
  • International Standard 1/2” microphine capsule with Class 1 & Class 2 variants
  • Long Term Stability & Reliability
  • High Accuracy
  • Ideal for OEM Specifications & Replacement

MV:220A Preamplifier

  • Compatible with pre-polarised 1/2" microphone capsules
  • Constant current powered (IEP/ICP Type)
  • BNC output connector
  • Supports up to 100m of microphone cable

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Find out more

If you have any questions or if you would like any more information, please contact us and we will be pleased to help.

From the UK, contact us on 01723 891655.

From outside the UK, please contact us on +44 1723 891655.

You can also contact us via our contact form.

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