Lexicon CORE2, Руководство по обслуживанию

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Lexicon
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14. Using optical cable, connect the Optical Output on the back of the Core2 card to the Digital Distortion
Analyzer.
15. In the Routing area, activate the Optical S/PDIF Out by checking the Optical box.
16. Move the Audio Input cable back to the analog #1.
17. Repeat steps 10 and 11 and check for THD+N specification.
Digital In To Analog Out THD+N Test:
These tests check the THD+N of the digital input to analog output path.
1. Apply a 1kHz signal @ -1.0dBFS signal from the Digital Function Generator to the S/PDIF IN on the
Core2 Connector Box.
2. Connect the analog output marked #1 on the Core2 Connector Box to the Analog Distortion Analyzer
set to measure THD+N.
3. On the Analyzer, engage the 20Hz to 20kHz audio bandpass filters.
4. Open the LexPanel by double clicking on the Lexicon Studio Icon.
5. Click on the Core2 tab to bring it forward. In the Routing area, activate the S/PDIF In, Analog Outputs 1-
4, and Output 5-8 buttons by clicking on each of them. If Optical is enabled (checked), disable it.
6. To activate your Routing selections, click on the Apply button, if it is flashing. There is no need to click
the Apply button if it is not flashing.
7. Click on the Clock Source tab to bring it forward. In the Clock Source menu, select S/PDIF.
8. Click on the Punch tab to bring it forward. To enable your Input Source and Output Destinations
selected from the Core2 tab, make sure the enable punch check-box is selected (it will have a check in
the box if enabled).
9. Hold the CTRL key down on the computer keypad, then in the Sources menu, select S/PDIF In L and
S/PDIF In R.
10. Hold the CTRL key down and select all the D/A outputs 1-8 in the Destinations menu.
11. Sweep the Oscillator from 20Hz to 20kHz and verify the analog output is < .005%.
12. To test the remaining Outputs move the output cable from the #1 analog output to each of the
remaining outputs, 2-8, test for the audio spec as described above.
13. The above test needs to be repeated for the S/PDIF Optical input connection of the Core2.
14. Disconnect the Coax S/PDIF input.
15. Using optical cable connect the Digital Function Generator to the Optical Input on the back of the Core2
card as described in Step 1 above.
16. In the Routing area, activate the Optical S/PDIF by checking the Optical box.
17. Repeat step 11 and 12 and check for THD+N specification.
Crosstalk Tests:
The crosstalk tests measure the amount of signal that bleeds through from one channel to the other.
Analog In To Digital Out Crosstalk Test:
1. Apply a 1kHz signal @ +8.0dBv from the Analog Low Distortion Oscillator to the Analog Input marked
#2 on the Core2 Connector Box.
2. Connect the digital output marked S/PDIF on the Core2 Connector Box to the Digital Distortion
Analyzer.
3. Open the LexPanel by double clicking on the Lexicon Studio Icon.
4. Click on the Core2 tab to bring it forward. In the Routing area, activate the Analog Inputs and S/PDIF
Out buttons by clicking on them. If Optical is enabled (checked), disable it.
5. To activate your Routing selections, click on the Apply button, if it is flashing. There is no need to click
the Apply button if it is not flashing.
6. Click on the Clock Source tab to bring it forward. In the Clock Source menu, select Internal and set the
Sample Rate to 44100.