Figure 22
Figure 23
Procedure
To avoid errors from airbourne background noise and electrical interference, switch off all sources in the room such as air conditioning, refrigerators etc.
Laptop computer settings:
Run the laptop from its battery and disconnect its transformer power supply when taking measurements. This will prevent noise being generated by electrical grounding mismatches between the laptop, sound card and CT8 XO. Make sure the battery is fully charged before starting the measuring procedure.
Open the “Sounds and Audio Devices” window in “Control Panel”. Click on the “Sounds” tab and select the “No Sound” option in the “Sound Scheme”
Click on the “Volume” button in the “Sound Playback” section and make sure the Microphone “Mute” box is checked to prevent feedback.
Click on the “Audio” tab and then on the “Volume” button in the “Sound Recording” section. Set the volume slider to maximum and make sure the “Select” box is checked.
Set Bank 1 switch 1 to ON to accept an input from the front of the CT8 XO.
Set Bank 2 switches 2 and 3 to OFF to disable the parametric equalisers.
Set the Low- and
Connect the output of the sound card to a front test input socket of the CT8 XO and the microphone to the input of the sound card.
Open WinMLS2004
From the menu, select Setup…Load… and load the setup called “B&W CT800” from the “Sound System” folder.
Click the button to open the “Volume and Input Levels” window.
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