Sound and Vibration Instrument Hire and Calibration

Bruel & Kjaer 2250 + BZ 7230 FFT Software

The B&K 2250 multi-function meter is designed for all sound and vibration measurements, analysis and recording applications. This page describes the optional BZ 7230 FFT - Fast Fourier Transform Software

For information on other features, options and accessories click any relevant blue link

Optional application module that transforms the 2250 Sound Level Meters into hand-held FFT analysers. The FFT (Fast Fourier Transform) algorithm is a measurement technique that gives narrow-band filtering using post-processing of a digital time record. The FFT analysis is carried out in real-time.

With the possibility to define reference spectra and tolerance windows, it is the tool of choice for measurement and diagnostics of machinery noise and vibration. Together with the optional add-on Tone Assessment BZ-7231, it allows objective tone assessment in the field.

One shot measurements
With 6400 FFT lines, you can take measurements with both a wide frequency range and high resolution - in one go. If you do not need the wide range, you can further improve resolution by utilising the FFT lines over a limited range. If you do not need the resolution, you can save measurement time by selecting a smaller number of lines.

Zoom in for detailed insight
Should your FFT measurement show a strange, unexplainable peak, you can just tap and select the range you want to analyse in more detail, press 'Zoom', and repeat the measurement. The Zoom FFT function lets you utilise the many FFT lines to dig down into the smallest details around any frequency you like, with a frequency resolution of up to 16 mHz.

Read between the FFT lines
Standard FFT analysis only gives results at a number of discrete frequencies, defined by the chosen frequency range and number of FFT lines. As a result, both the frequency and level of indicated peaks may be misleading. However, by activating the frequency correction function you find the true peaks and their levels between the lines, with a frequency resolution that is ten times better.

Many utilities just a few taps away
There are many utilities that enhance your FFT measurements, such as auto peak finding, max. hold spectrum or comparing a spectrum to a custom selected reference spectrum - and they are all easily activated.

Intuitive touch screen control
The high resolution touch screen allows you to easily step through the spectrum as well as zoom in and out. Delta, harmonic and other cursors quickly reveal the spectra’s properties, and let you carry out complex analysis on the go.

Compare products and components
Benchmark competitive and previous generation products: Use narrow-band analysis to identify forcing functions and resonances, to help set the standards for your next-generation product. The dual-overlay display makes it easy to compare measurements between design iterations.

Multi-purpose troubleshooting
Whether troubleshooting involves RPM monitoring, shaker excitation or finding a structure's resonance frequencies with a hammer, you can do it all with one analyser.

Easy interaction with complex criteria
Define comprehensive pass-fail criteria using up to ten tolerance windows, with each criterion based on the individual FFT lines or their sum in this window. Once set up, a simple pass-fail message at the DC output allows it to be part of a smart, streamlined production test system.

See also the : B&K 2250 BZ 7230 Specifications.