Steinberg Nuendo DD8 Mode D'emploi page 40

Besides the electrical differences, both formats also have a slightly differ-
ent setup. The two formats are principally compatible, because the audio
information is stored in the same place in the data stream. However,
there are blocks of additional information, which are different for both
standards. In the table, the meaning of the first byte (#0) is shown for
both formats. Already in the first bit there is the decision whether the fol-
lowing bits should be read as Professional or Consumer information.
Byte Mode Bit 0
0 Pro
0 Con P/C
As can be seen, the meaning of the following bits differs quite substan-
tially in both formats. If a device like a common DAT recorder only has
an SPDIF input, it usually understands only this format. In most cases, it
will switch off when being fed Professional-coded data. The table
shows that a Professional-coded signal would lead to malfunctions for
copy prohibition and emphasis, if being read as Consumer-coded data.
This actually happened in former times, but today it is not more than an
artificial functional restriction.
Nowadays, many devices with SPDIF input can handle Professional
subcode. Devices with AES3 input almost always accept Consumer SP-
DIF (passive cable adapter necessary).
11.3 Clock De-coupling using the SRC
Master-slave problems occur at the latest with the use of a digital
mixer. For 'normal' use of CD-Player, DAT and harddisk recording, the
tasks are clearly defined. The device playing back is the master in each
case, the recording device the slave. The CD-Player delivers the clock
and the DAT synchronizes to it.
When working with a digital mixer, the CD-Player would be the master
and the mixer the slave. This model breaks down with a single stroke, if
a DAT is also being connected, which is not recording, but also playing
back. Every digital device can only synchronize to one source, the audio
data of the other sources is processed with errors due to missing syn-
chronization. Clicks and drop outs are the consequence.
NUENDO DD 8
English – 40
1 2
P/C Audio?
Audio? Copy
3 4
Emphasis Locked
Emphasis
5 6 7
Sample Freq.
Mode