Lexicon CORE2, Service Manual

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Lexicon Studio Core2 Service Manual
4-8
4. 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.
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 S/PDIF.
7. 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).
8. Hold the CTRL key down on the computer keypad then in the Sources menu S/PDIF In L and S/PDIF In
R.
9. Hold the CTRL key down and select all the D/A outputs 1-8 in the Destinations menu.
10. Take a 0dB reference reading on the analyzer.
11. Sweep the Oscillator from 20Hz to 20kHz and verify the analog output is +/- 1dBr.
12. To test the remaining Outputs move the output cable from the #1 analog output to each of the
remaining outputs 2-8 and test the audio as described above for audio defects.
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 10 and 12 and check for Frequency specification.
THD+N Measurement:
Analog In To Digital Out THD+N Test:
These tests check the THD+N of the analog input to digital output path.
1. Connect the Analog Low Distortion Oscillator to the Analog Input marked #1 on the Core2 Connector
Box.
2. Connect the digital output marked S/PDIF on the Core2 Connector Box to the Digital Distortion
Analyzer set to measure THD+N.
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.
7. 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)..
8. Hold the CTRL key down on the computer keypad. In the Sources menu, select all A/D inputs 1-4.
9. Hold the CTRL key down and select S/PDIF Out L and S/PDIF Out R in the Destinations menu.
10. Apply the signal frequencies and levels as indicated in the table below and verify that the digital output
is within spec (< 0.005%). Do not take measurements while sweeping of frequencies. Set the level and
frequency and take each measurement independently.
Frequency (Hz) 20k 10k 6k 1k 100 20
Input Level (dBv) -5.00 -5.00 -5.00 -3.00 -3.00 -3.00
11. To test the remaining Inputs, move the input cable from the #1 analog input to each of the remaining
inputs 2-4 and test for the audio spec as described above.
12. The above test needs to be repeated for the S/PDIF Optical output connection of the Core2.
13. Disconnect the Coax S/PDIF Output.