Operation Manual
I-Tech HD DriveCore Series Power Amplifiers
page 52
I-Tech HD DriveCore Series Power Amplifiers
Operation Manual
page 53
12 Appendix A: Network and CobraNet Basics
Figure 12.1 A HiQnet Network
12.1 HiQnet Networks
Background
:
A
Local Area Network (LAN)
is a group of computers in a venue that
share data, either through cables or via wireless transmission.
Ethernet
is a popular
LAN communication protocol for PCs. An
audio network
is a Local Area Network
made of audio devices and one or more computers. A
subnet
is a small network within a
larger network. For example, an audio network might have two subnets: one for
enter tainment audio, and one for paging.
One use of an audio network is to control and monitor power amplifiers on stage from a
computer at Front-of-House. You can set amplifier levels, adjust crossovers, measure
speaker impedance, check for overheating and clipping, all from the house mixing
con sole.
You need a way to send computer commands to several audio devices at once. This is
done with an
Ethernet switch
, which is something like an audio Y cable or distribu tion
amp. The computer, and all the audio devices, connect to the switch as in Figure 12.1.
HiQnet
protocol lets you control and monitor cer tain Harman products (including
Crown) on an Ethernet network. Figure12.1 shows a typical HiQnet network.
HiQnet control offers many advantages:
•
Use of “off-the-shelf” network hardware.
HiQnet uses standard hardware
commonly used in the computer industry, making it both low-cost and readily available.
•
Better Performance.
Meters display faster in realtime because the network is wide
bandwidth.
HiQnet provides these functions:
•
Quickly find all HiQnet components connected to the network.
•
Synchronize multiple control points on a network.
•
Control and monitor components on different Local Area Networks (LANs) through the
use of an IP router (explained later).
•
Upgrade firmware via the network.
Network Addresses
Each component in a HiQnet network has three addresses to identify it:
•
Media Access Control (MAC) Address
•
Internet Protocol (IP) Address
•
HiQnet Address
Let’s explain each identifier.
Computer
Laptop
100Mb Switch
000
000
000
000
1 000
Figure 12.2 Multiple-Network Communication Via an IP Router
MAC address:
Short for Media Access Control, MAC is an address for an audio compo nent
that is burned into firmware in the component by its manufacturer, and cannot be changed.
Every component in a network has its own unique MAC address. The MAC address is printed
on a label outside the component. It is shown in hexadecimal format as 6 two-byte octets such
as:
00-0A-40-00-DC-2F
HiQnet Address:
When you set up a network with System Architect soft ware, you assign an
address to each component. Each component has its own address, numbered from 1 to
64,999.
Internet Protocol (IP) Address:
When you set up a network, you assign an IP address to
each component. The IP address identifies each component. That way, certain data can be
sent to the correct address (the correct component). An IP address has four numbers
sepa rated by periods. Each of the four numbers must be 0 to 255. For example:
192.168.0.1
Part of an IP address the network ID, and the remaining part is the host ID. The host ID is
either:
• A subnet number and a device address.
• A device address (if there is no subnet in the network).
To identify which part of the IP address is the network ID, you assign a
Subnet Mask
to the
network. A Subnet Mask
is four numbers (0-255) separated by periods. “255” means “this
part of the address is the network ID”. For example, if the subnet mask is 255.255.0.0, and the
IP address is 192.168.0.127, the network ID is 192.168.
IP Router
To communicate between different networks, you need an
IP Router
. Any control data or
monitor data that is sent to the other network must go through the IP Router.
The IP address allows components and computers on multiple networks to communicate with
each other through the use of an IP Router as shown in Figure 12.2.
Here is an application for a router. Wireless devices, because of bandwidth limitations, can not
be on a CobraNet network. However, the wireless devices can be on a non-CobraNet net work,
and access CobraNet devices through a router using IP addressing.
Discovery
is the process where System Architect finds all the devices on an audio network
and lists them on the computer screen. Discovery cannot be done through an IP router, so a
Discovery Proxy
is required. If you need to control or monitor components that are on
another subnet, you will need to specify ONE component on the remote network that can act
as a Discovery Proxy. Currently, all networked Crown products except the PIP Lite can
function in this capacity.
To add a Proxy, select Setup > Network Setup > Proxy addresses. Choose any one of the
components listed above, type its IP address in the box under Proxy Addresses, then click the
Add
button. To remove a Proxy, select the IP address in the list and click the
Remove
but ton.
Computer
Laptop
100Mb Switch
Lite
100Mb Switch
outer
Computer
ire e cce oi t
Laptop
ech power amp i ier
