MV 240 USB – The new generation of digital acoustic measurement technology

The MV 240 USB from Microtech Gefell, a further development of the MV 240 digital with an optimized new processor, is a sophisticated measurement microphone amplifier with integrated analog-to-digital converter, specially designed for precise acoustic measurements.

The range of applications for the MV 240 has been significantly expanded, for example, by the possibility of combining it with mobile devices.

Current development topics continue to include synchronisation via the time stamp of a GPS sensor, for example for pass-by solutions.

The most important features and functions at a glance:

🎤 Technical highlights

• Measurement microphone amplifier (1/2") with USB interface and lockable LEMO® connector
• Analog-to-digital conversion with two level ranges, combined into a 32-bit USB output signal
• Dynamic range: 7 dB(A) to 160 dB – covers the entire range of typical measurement microphone capsules 
• Sampling rates: 48 kHz, 96 kHz, and 192 kHz – suitable for measurements up to approx. 80 kHz
• Polarization voltage: generated internally, 200 V switchable or deactivatable for electret capsules
• Driverless operation: automatically recognized by Windows, macOS, and Linux
• Expansion of the application area through optimized possibility of combination with mobile devices

🧠 Special features

• Calibrated output: The digital output signal corresponds to already calibrated sound pressure values.
• Integrated generators: for checking the measurement chain and determining the reference point for 1 pascal sound pressure.
• Modular design: compatible with various capsule types (e.g., Microtech Gefell, Bruel & Kjaer, GRAS, PCB).

🛠 Areas of application, e.g.:

• Environmental and occupational safety measurements
• Room acoustics and long-term sound recordings
• Research & development, training, and industrial quality assurance

Noteworthy features include, for example:

• Digital measuring microphone with 32-bit data transmission
• Digital transmission of fixed calibrated sound pressure values
• Full dynamics of a newly developed low-noise 1/2“ capsule (with ¼” capsule insert – maximum sound pressure level 160 dB)
• User independence from special company software, possibility of using common measurement software and compatible with all common operating systems

MV 240 USB as a measurement microphone

Equipped with a new, specially developed high-end capsule with low noise and new integrated electronics (including an integrated AD converter) tailored to the capsules, the MV 240 USB significantly expands the circle of potential users as a measurement microphone. The disadvantages of previous AD solutions, such as complex operation and time-consuming installation, potential sources of error due to the complicated coordination of multiple electronic components, and the resulting time and personnel costs, are eliminated.

The MV 240 USB replaces two analog measurement microphones, two analog front-end channels, and part of the digital signal processing, resulting in significant cost savings. In addition, no separate power supply is required, as is common with analog measurement microphones when their full dynamic range is to be used.

Wide range of applications

Current examples of applications include use in weatherproof microphone units of the WME 980 series for environmentally relevant noise measurements or in the field of study and training as well as in research and development.

In addition to noise measurements, the most important areas of application include test benches for outdoor noise measurements in the automotive sector, which are important for official vehicle registration, vehicle development, and quality assurance in production.

This is also relevant for study and training as well as for R&D. Access to high-quality measuring instruments and methods is essential for a sound university education of future technicians and R&D specialists with broad practical knowledge.

With the MV 240 USB, every student, researcher, and developer has access to a cost-effective, high-quality measuring device that is suitable for research and industrial applications and can be connected to standard computer technology with Windows® or Linux®-based operating systems without additional technical requirements, such as a digital sound interface.

Programming, measurement, and measurement evaluation are also possible in systems such as Phyton®, C++®, MATLAB®, or Labview® with the integration of the digital measuring microphone.