Digital Audio Interfacing and Networking 148139.5.9 XLD Connector for AES3-MIC Applications
AES42 describes but does not require the use of a new
connector called the XLD for AES3-MIC applications.
It is a variant on the common XLR-type connector with
the addition of keying. This connector was designed by
Neutrik and is not in production as of this writing.
The reason for this connector is to prevent accidental
interconnection between analog and digital circuits, and
in particular between analog and AES3-MIC circuits.
The keying was designed to be field removable so if
someone were required to use the same cabling for both
analog and digital applications that would still be
possible, Figs. 39-14–Fig. 39-18.
A number of those involved with the AES42 effort
felt that some such connector that prevents accidental
interconnections is mandatory given the use of the rela-
tively high current DPP. They feared it might damage
analog outputs to which it might be accidentally
connected. Others favored a different connector than the
XLR because of the years of experience troubleshooting
mismated analog and digital circuit connections. It was
pointed out that this issue would be better addressed by
the group responsible for AES3 revisions. There was
also a group that felt that given the large amount of
existing infrastructure using the XLR for AES3 circuits,
any change was unacceptable. As a compromise, the
standard was issued with the proposed new XLD
connector described but not required.
According to AES42 the issue of what connector to
use for AES3-MIC applications is under consideration
by the AES Standards Committee. Meanwhile, the
XLR-3 as currently specified for AES3 may be used. If
a new connector is selected for AES3 applications, thenThe information is sent as two binary coded decimal (BCD) dig-
its. The L-nibble or lower nibble is sent with its LSB in bit 0, and
MSB in bit 3. The U-nibble or upper nibble is sent with its LSB in
bit 4, and MSB in bit 7. Numbers less than 10 are coded with a
leading 0 in the U-nibble.
Bytes 9 and 10 together represent the entire hardware revision
number with a range of 00.00 to 99.99. Byte 9 is the integer por-
tion while byte 10 is the fractional portion.
Status Data Page 2 Byte 11—Microphone Software Revision Main
Counter
The information is sent as two binary coded decimal (BCD) dig-
its. The L-nibble or lower nibble is sent with its LSB in bit 0, and
MSB in bit 3. The U-nibble or upper nibble is sent with its LSB in
bit 4, and MSB in bit 7. Numbers less than 10 are coded with a
leading 0 in the U-nibble.
Status Data Page 2 Byte 12—Microphone Software Revision
Index Counter
The information is sent as two binary coded decimal (BCD) dig-
its. The L-nibble or lower nibble is sent with its LSB in bit 0, and
MSB in bit 3. The U-nibble or upper nibble is sent with its LSB in
bit 4, and MSB in bit 7. Numbers less than 10 are coded with a
leading 0 in the U-nibble.
Bytes 11 and 12 together represent the entire software revision
number with a range of 00.00 to 99.99. Byte 11 is the integer por-
tion while byte 12 is the fractional portion.
Status Data Page 2 Bytes 13–23—Reserved
All bits of Page 2 Bytes 13–23 are reserved and should be set to 0.Table 39-3. Status Data Page (Continued)Figure 39-14. Fully coded male cable variety. This is a
modified XLR type of connector with removable keying
that could be used to prevent accidental interconnections
between analog and AES3 fully coded female XLD.Figure 39-15. AES42 proposed XLD connector of the half-
coded male cable variety. This is a modified XLR type of
connector. It will mate with a standard female XLR or a
fully coded female XLD.Figure 39-16. AES42 proposed XLD connector of the half-
coded female chassis variety. This is a modified XLR type of
connector. It will mate with a standard male XLR or a half-
or fully coded male XLD.1 2
31 2
32 1
3Push