Technology

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Technology
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What is CobraNet ?

• CobraNet is a combination of software, hardware
  and network protocol which allows distribution of
  many channels of real-time, high quality digital
  audio over an Ethernet network.
• CobraNet uses standard Ethernet packets and
  network infrastructure (controllers, repeaters,
  switches, cabling).
• Audio is delivered in standard Ethernet packets
  over 100Mbit Fast Ethernet.
• 10Mbit Ethernet varieties (10BASE-T, Coaxial) are
  not supported due to their limited bandwidth.

IU Instructions
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What is the audio delay through CobraNet?

• 256 samples (5-1/3 milliseconds thousands of a
  second) of delay is incurred by the buffering of
  audio data into Ethernet packets in CobraNet
  transmitters and receivers. Additional delay is
  incurred in analog to digital conversion, digital
  to analog conversion and sample rate conversion.
  These additional delays are usually on the order
  of dozens of samples.
• Data on an Ethernet network travels at the speed
  of light. The time for data to traverse a 2
  kilometer network is several microseconds
  (millionths of a second). This delay is
  inconsequential in light of the delays enumerated
  above. Therefore, the audio delay is considered
  constant from any input to any output anywhere on
  the network.

IU Instructions
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Can I run CobraNet over an existing LAN?

• Yes. As long as you're using a switched network,
  traffic from other network devices such as PCs
  can coexist on the same network with CobraNet
  devices.

PC
PC
CobraNet Interface
Cat5 Max. 100m
Switch
Switch
PC
PC
CobraNet Interface
IU Instructions
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Terminology

• Bosch CobraNet Interface
• Device that contains a CobraNet interface board
• CobraNet Interface board
• HW and SW supplied by Peak Audio (CM1)
• Conductor
• CobraNet interface provides Master clock and
  transmission arbitration for the network. There
  can only be one conductor!!

IU Instructions
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Terminology

• Audio Channel
• Single audio channel,
• 48kHz sample rate, 16-20-24 bit resolution
• Bundle
• Can carry 0-8 audio channels
• Bundles are numbered from 1 65279
• A bundle has a single transmitter

IU Instructions
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Terminology

• Multicast Bundle
• Point to multi point connection
• Bundle 1 255 are multicast bundles
• Audio is always transmitted, even when no one is
• receiving
• Unicast Bundle
• Point to point connection
• Bundle 256 65279 are unicast bundles
• Audio is only transmitted if a receiver is
  connected to the same bundle

IU Instructions
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Basics
Ethernet
IU Instructions
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Basics
Ethernet
Block diagram
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IU Instructions
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Basics
Audio Expander
Audio Expander
Screened microphone cables
IU Instructions
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Basics
CobraNet interface
CobraNet interface
Unicast Bundles
Ethernet
IU Instructions
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Basics
CobraNet interface
CobraNet interface
CAT5 (Cross cable)
IU Instructions
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Basics
Audio Expander
Audio Expander
IU Instructions
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Basics
CobraNet interface
CobraNet interface
Unicast Multicast Bundles
Ethernet
IU Instructions
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Basics
CobraNet interface
CobraNet interface
Switch
IU Instructions
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Technology

• End of section

CobraNet Menu