dCS 954 User Manual

Manual for Standard Software Version 1.5x

dCS Ltd

June 2000

IMPORTANT! If the selected format does not match the source(s) connected, the audio output may be severely aliased mono or aliased mono mixes of the sources. This should pose no risk to ears or speakers (assuming the system gain is set sensibly) but cannot be detected by the unit without correct messaging.

The unit stores the last input selection at power down and re-loads it when power is restored. For example, if the previous setting was Quad AES, the unit will return to this mode at power up, provided all 4 AES inputs are valid and carry the same sample rate. The unit will detect the sample rate present on AES1 and lock to it. If one or more inputs are disconnected, the unit will lock to Single AES on AES1 until the required inputs are available.

Your dCS 954 can automatically select the data format. For details, see the menu option I For on page 25.

To use the unit in DSD mode, see the menu entry for DSD on page 20.

The Active Input button is the source selector button below a bright LED or, if the unit is unlocked, a flashing LED. On its own or with the other source selector buttons, the blue text on the panel applies. With the other menu buttons (white type on the front panel) it is the menu Step button.

For Menu operation as the Step button, see the section “The Software – the Menu” on page 18.

Coarse Lock

Some digital audio equipment (even some quite expensive products) produces data streams with a level of jitter outside the AES3 specification. In particular, sources that involve mechanical movement between tracks (for example, some CD players) can show large timing transients as the movement occurs, which can upset the dCS 954, causing intermittent data errors or muting. To cater for this situation, the dCS 954 allows two PLL settings – fine lock and coarse lock. If the problem arises, pressing the Coarse Lock button forces the unit to use the coarse lock mode, which may solve the problem. The LED indicates that coarse lock is selected.

Unless necessary to maintain a stable lock, coarse lock should be turned off it will cause degraded audio quality. It should only be used where degraded audio is better than no audio!. For more information on this topic, see section “Jitter and PLL bandwidths” on page 68

Note that the use of unscreened digital audio cables can occasionally cause the unit to mute and re-lock, if they allow in gross interference from some nearby source.

Lock Indicator

When lit, this indicates that the front panel controls are locked out to prevent accidental or unauthorised operation. Lock is turned on and off using the Loc menu option, see page 28.

Manual part no: DOC136954 iss 2B1

Page 13

file 135954ma2b1.pdf available from website

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