dCS 974 User Manual

Manual for Software Version 1.0x

dCS Ltd

May 2001

Output audio bandwidth is low.

•During sample rate conversion, the signal is digitally filtered - this is essential for good performance. The output audio bandwidth will usually be slightly less than half the lowest sample frequency involved in the conversion.

A stereo output signal is expected but signal is present on one channel only.

•Check that Balance is not set to one side.

•If PCM SDIF-2 or DSD SDIF-2 is used, check that CH1 OUT and CH2 OUT are both connected.

•Check you are not using a Dual AES mode with just one cable connected.

A stereo output signal is expected but one channel of the input appears on both channels of the output.

•Check that the receiving unit expects two wire AES or SPDIF mode, rather than double speed, single wire.

Tone appears on the outputs.

•Press the Status button and check that the label is NOT visible. If it is, select Test Mode and set the Test Generator to Off.

•Low level “idle tones” sometimes appear on the outputs if the signal on the input drops to a level below the output word length and Noise Shaping is on with no Dither. This may arise during editing sessions, for example, where digital silence is coming in to the unit, but the Detect Silence function is off. This situation will usually not arise if an unedited input from an ADC is being used, although even in these circumstances, enough noise shaping must be used. Consider using either Dither or Detect Silence or both.

The LCD display is unreadable but the Power LED and possibly some other LEDs are lit.

•Display Contrast may have been set to minimum. Switch off the unit, wait 10 seconds, hold down the Status button and switch on. The unit will power up using default settings, including high contrast. Alternatively, Store A is pre-loaded with default settings. Press Recall slowly twice, then press Enter to recall from it.

Strange characters appear on the LCD display.

•This can be caused by power line drop-outs or switching the unit off and on rapidly. Switch off, wait 10 seconds then switch on - normal operation should be resumed.

The stereo image is poor or out of position.

•Check that Phase and Swap Channels are set to Normal.

•Check that Balance is correctly set.

•It may be that the input signals are out of phase, swapped or out of balance. Use the units controls to correct this.

•If using the DSD/SDIF interface, the CH1 & CH2 cables may be swapped.

•If you are using a Dual AES or Quad AES mode from some other equipment, make sure you used the right outputs from that.

Maximise fails to increase the signal level to full scale.

•The range of the Maximise function is limited to +12dB. If the input signal peaks are smaller than -12dB0, Maximise will apply +12dB of gain. A second pass will apply up to 12dB more gain.

Manual part no: DOC1241121A1

Page 121

Document No: OS-MA-A0124-112.1A1

Contact dCS on + 44 1799 531 999

email to: more@dcsltd.co.uk

(inside the UK replace + 44 with 0)

web site: www.dcsltd.co.uk