User manual RANE NM 84

[. . . ] OPERATORS MANUAL NETWORK PREAMPLIFIER NM 84 Quick Start Why is it that the hardest thing about writing the Quick Start is the opening line?Only thats hard to say with a straight face but if you are going to jump right into this thing without reading all of our hard work, then thats where you begin. A dedicated network for CobraNet audio is recommended, but not required when using switched networks. The NM 84s CobraNet technology utilizes standard 100Base-T Ethernet hardware. [. . . ] Network Hardware More costly than non-managed switches, but worth the expense for many systems due to their advantages. 101 designs. As with many technologies, repeater bus have had their day and may soon be a thing of the past. The second kind of network hardware devices are called switched hubs which are only a little bit more expensive than repeater hubs. Using switches for your network greatly increases the efficiency of the network and allows computer data to be shared on the network. Switches automatically view the IP address (destination) of all incoming data and only send the data out the single required port for delivery, therefore, switches are unicast (point-to-point) devices. Switches are the more common network hardware devices used for CobraNet networks. Switched hubs are like the Junior or Senior class of the network world. Similar to a switch but the next step up the rung managed switches can be user-configured in several ways: you can create Virtual LANs (VLANs) and change the network architecture among various VLAN setups; you can set the managed switch up to prioritize the incoming data so audio data has higher priority than computer data, for example. With such capabilities, you can see that managed switches are not simple, Networking 101 devices theyre more like the Ph. D. The fourth network hardware device to introduce is called a media converter. These are devices that convert the electri- cal signal from a set of copper wires (e. g. , CAT 5 cable) to the light signal of the fiber optic world. Use media converters when the distance between network nodes exceeds the 100 meter limitation of copper cable. Delay Times. There is an inherent delay between when audio enters and exits a CobraNet network. For the NM 84, the delay from when analog audio enters the device until it appears at the analog output of another NM 84 on a typical, small network is specified by three numbers. They are CobraNets fixed 5. 33 milliseconds and the A/D and D/A propagation delays all of which are specified separately on the NM 84 Data Sheet. The A/D time gets you onto the network; the network delay is fixed between any CobraNet devices; the D/A time is the time between the arrival of the CobraNet audio and the analog audio exiting from the Monitor Outputs when theyre configured to monitor Network audio. (See the Peak Audio FAQ web page about the maximum number of switch hops and delay times through network hardware devices. ) Your application dictates whether this propagation delay is acceptable or not. Most CobraNet applications wont have to worry about this, but just to provide some insight, heres two applications that may not like this delay. For example, a theater with an elevated center cluster that provides coverage Manual-10 for listeners in the initial, center seats may not find this delay acceptable. Assuming that no propagation delay is added through other digital signal processing or a digital console (this may be the case), the additional network delay of 6. 5175 feet assuming NM 84s on and off the network may place the arrival time of the direct sound versus the acoustic arrival outside the Haas effect time. This would make the propagation delay unacceptable for this application. If youre implementing a mic snake type of application and are including the monitor audio for stage members on the network, be sure to not exceed an acceptable delay time; a delay time not much more than 10 milliseconds (or hopefully less) is probably acceptable for monitor applications. That being said, there are upcoming technologies (i. e. , vaporware) that may cut this network propagation time in half or more. [. . . ] It is possible, even common to build a network from a combination of interconnected Repeater Hubs and Switched Hubs. - A Switching Hub, or simply "Switch", Hub is not a technically concise term. The term can be Isochronous used to refer to either a Repeater Hub or a Switching Hub. Uniform in time; of equal time; performed in equal times; recurring at regular intervals. [. . . ]