User`s manual
Table Of Contents
- CONTENTS
- 1 INTRODUCTION
- 2 THE CLIO SYSTEM
- 3 CLIO INSTALLATION
- 3.1 MINIMUM PC CONFIGURATION
- 3.2 FW-01 DRIVERS INSTALLATION UNDER WINDOWS XP
- 3.3 FW-01 DRIVERS INSTALLATION UNDER WINDOWS VISTA AND 7
- 3.4 SOFTWARE INSTALLATION
- 3.5 THE 'CLIO BOX'
- 3.6 RUNNING CLIO FOR THE FIRST TIME
- 3.7 SYSTEM CALIBRATION
- 3.8 CLIO SERIAL NUMBER AND DEMO MODE
- 3.9 TROUBLESHOOTING CLIO INSTALLATION
- 4 CLIO BASICS
- 5 SYSTEM OPERATIONS AND SETTINGS
- 6 COMMON MEASUREMENT INTERFACE
- 7 SIGNAL GENERATOR
- 8 MULTI-METER
- 9 FFT, RTA AND “LIVE” TRANSFER FUNCTION
- 10 MLS & LOG CHIRP
- 11 SINUSOIDAL
- 12 WATERFALL , DIRECTIVITY & 3D
- 12.1 INTRODUCTION
- 12.2 WATERFALL, DIRECTIVITY & 3D CONTROL PANEL
- 12.3 WATERFALL SPECIFIC CONTROLS
- 12.4 MAKING A CUMULATIVE SPECTRAL DECAY
- 12.5 DIRECTIVITY SPECIFIC CONTROLS
- 12.6 MEASURING LOUDSPEAKER SINGLE POLAR DATA (1D MODE)
- 12.7 REPRESENTING SINGLE POLAR DATA
- 12.8 3D SPECIFIC CONTROLS
- 12.9 MEASURING LOUDSPEAKER SINGLE POLAR DATA (3D MODE)
- 12.10 MEASURING FULL SPHERE LOUDSPEAKER POLAR DATA (3D MODE)
- 12.11 REPRESENTING 3D BALLOON DATA
- 12.12 EXPORT 3D BALLOON DATA
- 13 MEASURING IMPEDANCE AND T&S PARAMETERS
- 14 LINEARITY & DISTORTION
- 15 ACOUSTICAL PARAMETERS
- 16 Leq LEVEL ANALYSIS
- 17 WOW AND FLUTTER
- 18 WAVELET ANALYSIS
- BIBLIOGRAPHY
- NORMS
10 MLS & LOG CHIRP
10.1 INTRODUCTION
Within this menu two different technique are available that yields to the final result,
the complex transfer function of a generic device. They are MLS and LOG CHIRP
Analysis. While the internal processing is quite different the result is the same and
this justify keeping them together. Advantages of each approach will be described
later in this chapter briefly, leaving to the bibliography for details.
MLS stands for Maximum Length Sequences, is a powerful well established
technique that allows you to carry out analysis of linear systems recovering the
Impulse Response of the device using a fast cross-correlation algorithm . It is
therefore a Time based analysis. Frequency domain information is obtained
calculating the Fast Fourier Transform, hereafter FFT, of the impulse response.
LOG CHIRP analysis uses a log-swept sine chirp as stimuli. The Frequency Response
is obtained with a deconvolution process and the impulse response with an Inverse
FFT of the Frequency Response
Both approaches carry a crucial piece of information in the time domain, the
Impulse Response. MLS & LOG CHIRP is therefore particularly well suited for
recovering the anechoic sound pressure response of a loudspeaker. i.e. the
frequency response of a loudspeaker as if it where positioned in an anechoic room,
while carrying out the measurement in a normal room. Just as importantly MLS &
LOG CHIRP allows complete evaluation of room acoustic parameters.
Within this Menu the user will be able to switch from time domain to frequency
domain and back using the powerful post processing tools CLIO provides. This
allows the collection of very sophisticated and complete information of any electro-
acoustic device. Both the theory behind all of this and the amount of parameters
that affect the measurement results make this Menu probably the most complicate
to use. We will skip the theory completely and after a concise description of the
whole User interface we will deal with real life applications.
10.2 MLS & LOG CHIRP CONTROL PANEL
Figure 10.1
10 MLS & LOG CHIRP 115