Rub and Buzz Effects

[LaRisa_M]

Overview

This post includes two VIs: one which calculates the rub and buzz of an input waveform and another that calculates the rub and buzz of a multifunction DAQ or DSA device.

Description

Rattle noise or rub and buzz are part of a class of non-linear, irregular, impulsive, and unwanted distortion effects which are not normally found with regular units under test (UUTs), rather they are typically produced by mechanical and structural defects in the UUT.  Due to short pulses of very low energy, traditional testing and analysis methods like RMS-FFT and Total Harmonic Distortion (THD) are not useful. 

Two VIs are included with this document:

• Rub and Buzz Measurement Example (DAQmx)
• Rub and Buzz Analysis VI

Add this rub and buzz measurement VI into your application to calculate the rub and buzz percentage of your audio system components.  The VI utilizes THD and harmonic analysis data from the THD VI in the NI Sound and Vibration Toolkit.  Users can configure the minimum and maximum harmonic to calculate rub and buzz percentage from.

A Rub & Buzz and High Order Harmonic Analysis tutorial can be found here.

Steps to Execute Code

1. Download rub_and_buzz-daqmx.vi

2. Configure the DAQ or DSA device you are using on the front panel

3. Run the code

4. Switch to the THD tab to see the rub and buzz value that has been calculated

Requirements to Run

Software

LabVIEW 8.5 or later

NI Sound and Vibration Measurement Suite or NI Sound and Vibration Toolkit compatible with your version of LabVIEW

Hardware

For rub_and_buzz.vi: N/A

For rub_and_buzz-daqmx.vi: A DSA or DAQ device compatible with NI-DAQmx

Additional Images

Front Panel