Download ARTA-HANDBOOK

Contents
1.
First steps with ARTA .................................................................................................................... 5
1.1.
Setup ....................................................................................................................................... 5
1.2.
Equipment ............................................................................................................................... 5
1.3.
Pin assignment for cables and connectors............................................................................. 10
1.4.
Measurement setup ............................................................................................................... 11
2.
Quick setup with ARTA ............................................................................................................... 13
3.
The ARTA measurement box ....................................................................................................... 17
4.
3.1.
Two-channel calibrated measurements with the ARTA measurement box .......................... 19
3.2.
Single-channel measurement calibration .............................................................................. 22
Soundcard setup and testing .......................................................................................................... 24
4.1.
4.1.1.
Windows 2000/XP WDM driver setup ......................................................................... 25
4.1.2.
Vista/Windows 7 WDM driver setup ............................................................................ 27
4.1.3.
ASIO driver setup ......................................................................................................... 30
4.2.
5.
Testing the soundcard ........................................................................................................... 31
Calibration of the measurement chain .......................................................................................... 40
5.1.
Soundcard calibration ........................................................................................................... 40
5.1.1.
Calibration of the output channel .................................................................................. 41
5.1.2.
Calibration of the input channel .................................................................................... 42
5.2.
Microphone calibration ......................................................................................................... 44
5.2.1.
Use of manufacturer's data ............................................................................................ 44
5.2.2.
Nearfield method........................................................................................................... 45
5.2.3.
Tweeter method............................................................................................................. 49
5.3.
Microphone frequency compensation ................................................................................... 51
5.3.1.
Calibration using a reference quality microphone >200Hz .......................................... 52
5.3.2.
Calibration below 500Hz with a pressure chamber ...................................................... 55
5.4.
6.
Soundcard setup .................................................................................................................... 24
Testing the amplifier ............................................................................................................. 58
Measurement with ARTA ............................................................................................................. 65
6.1.
General .................................................................................................................................. 65
6.1.1.
Test leads ...................................................................................................................... 65
6.1.2.
The signal-to-noise ratio of the measurement system ................................................... 66
6.1.3.
Averaging ...................................................................................................................... 68
6.2.
ARTA excitation signals ....................................................................................................... 70
6.2.1.
Impulse responses: theory and practice......................................................................... 74
6.2.2.
Phase and group delay................................................................................................... 78
6.3.
Where to measure: the measurement environment ............................................................... 83
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