Data AcQuisition And Real-Time AnalysisScope - Spectrum - Spectrogram - Signal Generator
Software for Windows
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Meter / Match Mode Control
Ideally, your computer should be able to perform an Auto-Calibrate operation by monitoring the output level using the sound card input, while the output is cycled through all the attenuator settings. But some older sound cards don't allow simultaneous input and output ("full-duplex") mode, so you may need to calibrate manually here.
There are two basic ways you can use these dialogs to help in calibrating your mixer attenuators: Direct measurement via a meter, or indirectly via matching two signals.
Regardless of which method you use, you will need to perform separate calibrations for both Wave and Master; these are separate attenuators which typically have totally different steps.
When you are calibrating the Wave output, set Master Volume to get a large overall output signal before you start. (For Match mode, both Left and Right Master should be equal; use the Volume Track button to simplify this.) If you are calibrating Master, set Wave Volume to get a large output instead.
The output should not be distorted when the range being calibrated is at maximum loudness, since the voltage will not properly track with attenuator changes. For these purposes you can judge distortion by ear: Use the Daqarta volume controls with the calibration (Wave or Master) volume at maximum, and run the other (Master or Wave) from low to high. If the quality or timbre of the sound changes above a certain step, it indicates distortion; set that volume control to the maximum undistorted step.
Note that although sound cards typically have only 16 or 32 actual steps on each attenuator, Windows pads this up to 192 overall by adding dummy steps to give higher apparent resolution. So during your manual calibration, expect to see many steps where there is no change from the prior step.
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