TL Audio VP-1 - Manual (Page 19)

meter monitoring digital output level. These related front panel controls and meters
will have no effect until the DO-1 card is fitted.
The DO-1 enables the VP-1 to directly interface with digital equipment that carries
these same format inputs, thus bypassing any A/D input stage.
4.38 Bit Rate Select.
A three position rotary switch enables the user to select whether a 16, 20 or 24 bit
word length is outputted by the DO-1’s digital outputs. The output is properly
dithered to the selected word length.
4.39 Sampling Frequency Select.
The DO-1 card is capable of generating a digital output at four different sampling
rates: 44.1, 48, 88.2 and 96kHz. These rates are selectable via a four position rotary
switch on the VP-1 front panel.
4.40 Digital Output Meter.
The output level generated by the DO-1 card is monitored via an 8 segment LED
ladder which registers levels from ‘SIG’ (signal present) through to digital CLIP,
which corresponds to a 0dBFS level sustained for several consecutive samples.
4.41 Lock
Status.
The Lock LED will illuminate when the VP-1 is locked to an external clock source
connected via the rear panel Wordclock input, assuming that the rear panel switch is
set to ‘External’ and the correct sample rate is selected (see 4.43). At all other times
the VP-1 will be synced to its own internal clock.
4.42 Output
formats.
The DO-1 card offers three separate output formats, all of which are active
simultaneously:
AES/EBU - a balanced pro format on 3 pin XLR, conforming to AES3 and
IEC60958-4 standard.
SPDIF - an unbalanced coaxial consumer style format on RCA phono, conforming to
IEC60958-3 standard.
Optical - offers an optical version of the SPDIF format on a TOSLINK optical
connector, with data conforming to IEC60958-3 standard.
4.43 Wordclock
Input.