Equipment
Our state-of-the-art equipment assures accurate and cost-effective vibration measurements. Two of the most useful pieces of equipment in our office are the Symphonie 01dB monitor and the Larson-Davis 2900B Real Time Analyzer, both used for advanced digital acquisition.   

The Larson-Davis 2900 is small, lightweight, and has many measuring applications. It is a precision sound level meter and a dual channel real-time frequency analyzer. It incorporates full, 1/3 Octave, or fine-line spectrum filters. This time-saving instrument gathers frequency domain data, and has the advantage of being self-contained and does not require a laptop to view the spectrum.

The Symphonie 01dB replaces traditional measurement instruments. It is compact and efficient, consisting of transducers (microphones, accelerometers or intensity probes) connected to a small acquisition unit which transfers data in real-time to a notebook computer. Viewing vibration levels in real-time allows simultaneous analyses in both time and frequency domains.

Fine-Line Spectrum and 1/3 Octave Band
Measurements are initially acquired as a fine-line spectrum. Using filter sets, vibration spectra can be segmented into various bandwidths, and measurements are included as octave band data in our surveys. Typical 1/3 octave band filtering further divides each full (1/1) octave band into three divisions covering 1/3 the original band.  Under ASTM standards the bands are from 1 Hz to 80 Hz for documenting the contribution of vibration. Vibration can be measured in three degrees of freedom: z is normally vertical, and x and y are the horizontal components.

Source-Path-Receiver Model
Controlling vibration within a planned structure, involves taking measurements on existing structures and developing a realistic source-path-receiver model.  Whether internal or external, vibration can be modeled in this manner. The location or magnitude of the source, attenuation of the path, and sensitivity of the receiver are the basic elements of the problem.
                                  
These measurements, combined with the standard methods of computer modeling, calculations and field measurements, produce a model more accurate and less costly to develop than a purely analytical model.

FEA can be used to predict how a floor assembly will react to different inputs of vibration. We can determine at what natural frequency the floor will respond, mode shapes, and maximum displacements.  FEA can be used to input field test data into the models, in order to simulate real-world vibration in a computer-simulated model.