Digital Audio Corporation MicroDAC IV User Manual

MicroDAC IV PORTABLE PROGRAMMABLE DIGITAL FILTER CONFIGURATION SOFTWARE USER’S MANUAL DIGITAL AUDIO CORPORATION A DRI COMPANY

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4 2. INSTALLATION 2.1 Software Requirements This Windows software-based product consists of an installation CD, User’s manual, and communications

5 3. MICRODAC IV CONFIGURATION CONTROL PANEL 3.1 MicroDAC IV Control Panel Figure 3-1 MicroDAC IV Control Panel At the top of the MicroDAC IV Co

6 • Mono Single configures the MicroDAC IV to apply a single large stage (Stage 1) of filtering to the Left Input only. When using the 2CH Adapti

7 3.4 Input or Output Highpass Filter The Highpass Filter controls are shown in Figure 3-3. The 200 Hz Highpass Filter is used to remove any low f

8 The MicroDAC IV Configuration Software allows the front panel controls to be locked to prevent accidental tampering by nontechnical operators. Th

9 Figure 3-7 Panel Lock Settings Windows The lock setting to be programmed into the MicroDAC along with the filter settings can be selected by cl

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11 4. PROGRAMMING THE MICRODAC IV 4.1 Selecting the correct COM Port The COM Port menu option within the File menu allows you to select the COM Po

12 Figure 4-3: MicroDAC IV Transfer Window Programming of the MicroDAC IV can be stopped at any time by pressing the Cancel button. A message wi

13 5. STORING FILTER CONFIGURATIONS 5.1 Save File Dialog Box Application: To save time configuring the MicroDAC IV control settings, complete se

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15 6. RECALLING FILTER CONFIGURATIONS 6.1 Open File Dialog Box Application: To save time configuring control settings in the MicroDAC IV control

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17 7. FILTER CONTROL WINDOWS 7.1 One channel adaptive filter Application: The 1CH Adaptive filter is used to automatically cancel predictable and

18 rescaled depending upon the input signal level. Overall convergence rate is faster with Auto. Adapt Algorithm: Selects the adaptive algorithm

19 Stopband Specifies amount in dB by which frequencies above Attenuation: the Cutoff Frequency are ultimately attenuated. Stopband attenuation

20 Description of controls is as follows: Cutoff Specifies frequency in Hertz below which all Frequency: signals are attenuated. Frequencies ab

21 Figure 7-6: Bandpass Filter Control Window Description of controls is as follows: Lower Specifies frequency in Hertz below which all Cutoff

22 7.5 Bandstop Filter Application: The Bandstop filter is used to decrease the energy level (lower the volume) of all signal frequencies abov

MicroDAC IV PORTABLE PROGRAMMABLE DIGITAL FILTER CONFIGURATION SOFTWARE User’s Manual March 31, 2003 Document Number: 990398 Version 1.0 DIGI

23 Frequency. Also, note that the Lower and Upper Transition Slopes always have different values; this is because the frequency width of an octave

24 Notch Limit: Specifies frequency in Hertz above which no notches are generated. Minimum Notch Limit is 2 and 1/2 times the Fundamental Notch F

25 of the noise. This is best done by adjusting the Notch Frequency up or down 1 Hz at a time while listening to the Notch filter output on the hea

26 To properly utilize the Slot filter, you will first need to identify the frequency of the signal to be isolated; this is best done using a Spe

27 7.9 20-Band Graphic Equalizer Application: The 20-band Graphic Equalizer is an easy-to-use linear-phase FIR digital filter that is used to r

28 The Spectral Graphic Equalizer is essentially a 115-band graphic equalizer; however, instead of having 115 separate slider controls, it allows

29 To draw the new filter curve, you will need to carefully click the mouse cursor on points within the filter display area which correspond to t

30 In this window, you can make the entire filter curve drop by a specified amount prior to editing the curve. This can be used to create headro

31 Figure 7-25: Normalized Spectral Graphic Equalizer This completes the Spectral Graphic Equalizer mini-tutorial. 7.11 Imported Coeffecient Fil

32 0.0008975 Scientific notation is in the form: mantissaE[+-]exponent The following are some examples of floating point coefficients in scientif

33 -7.269745E-002 -5.050633E-002 8.298883E-003 4.286449E-002 2.956892E-002 -8.256326E-003 -3.074622E-002 -1.991908E-002 8.1968

34 Figure 7-28 Two Channel Adaptive Filter Control Window Description of controls (Figure 7-28) is as follows: Filter Size: Used to set the n

35 8. ADJUSTING MAXIMUM TAPS FOR EACH STAGE A feature available on the MicroDAC IV is the ability to trade filter taps between stages in Mono Seri

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i TABLE OF CONTENTS 1. OVERVIEW ...

ii 8. ADJUSTING MAXIMUM TAPS FOR EACH STAGE...35

iii LIST OF FIGURES Figure 3-1 MicroDAC IV Control Panel ...

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2 1. OVERVIEW 1.1 Introduction The MicroDAC IV Configuration Software allows for complete setup and control of the three preset adaptive filters