360 Systems DigiCart/II Plus - Manual (Page 86)

74 • File Transfer Network DigiCart/II Plus Owner's Manual
Transfer Rates
SAMPLE RATE FORMAT
D-NET TRANSFER RATE
vs.
REAL TIME TRANSFER
AC-2 8:1
STEREO 1.5:1
48K
MONO 3:1
STEREO 1.6:1 44.1K
MONO 3.2:1
STEREO 2.25:1 32K
MONO 4.5:1
Electrical Specification For D-Net Transfers
File transfers may be accomplished via either of two digital audio interfaces:
AES-3ID (Proposed AES standard, 75
Ω impedance, BNC connector)
AES-3 (AES standard, 110
Ω impedance, XLR connector)
AES-3ID
The AES-3ID interface has been designed to operate using coaxial cable with a nominal
impedance of 75
Ω terminated with a male BNC. When the coax is directly connected
from a DigiCart/II Plus output to the input of another DigiCart/II Plus, the internal
electronics of the machines create a doubly terminated cable at 75
Ω. If other devices are
inserted in the data path (such as routers or switchers) the user should ensure that the
transmitting DigiCart/II Plus drives a nominal impedance of 75
Ω and that the receiving
DigiCart/II Plus is being driven by an output presenting a nominal 75
Ω output
impedance. This will serve to maintain correct signal amplitude and to minimize
transmission errors caused by signal reflections from the far end of the cable. Use of ‘T’
connectors to drive multiple DigiCart/II Pluses is not recommended as this would violate
the cable termination requirements.
The AES-3ID interface has been successfully tested using 150m of Belden 8281, 75
Ω
coaxial cable.
AES-3
The AES-3 interface has been designed in compliance with the AES-3 recommended
practice for serial transmission format for two-channel digital audio data. The connectors
required for this interface are described in IEC 268-12, and are XLR three-pin
connectors. The pin usage is:
PIN 1: CABLE SHIELD OR SIGNAL EARTH
PIN 2: SIGNAL
PIN 3: SIGNAL
Note: The polarity of pins 2 and 3 is not significant.