NM 1 Network Mic Preamp
General Description
The NM 1 Network Mic Preamp is a very versatile single channel CobraNet I/O box that finds use in many applications. The NM 1 presents matchless features in a compact, reliable, easy to install and maintain package. It has a single studio-grade microphone input with +48 volt phantom power, and a single amplifier output for connection to an external loudspeaker. The microphone signal can be transmitted over CobraNet and the amplifier input can be driven by any CobraNet audio channel. The NM 1 design is based on the Cirrus Logic CS18101 CobraNet chip and CM-2 reference design including the secondary CobraNet port for data and power supply redundancy (more on this later). It also has logic I/O on a DB-15 connector for reading external switches and driving indicator LEDs so it can be connected to a custom switch panel to implement microphone enable, busy indication and similar functions.
The feature that adds the most versatility to the NM 1 is Power Over Ethernet (PoE). It is fully compliant with the IEEE 802.3af standard as a Powered Device (PD). This means it's powered through the CAT 5 cable that connects it to an Ethernet switch. Of course, the Ethernet switch used must comply with the 802.3af standard as Power Supply Equipment (PSE); these switches are available from all the major Ethernet equipment manufacturers.
Think about this: the NM 1 does not need a power outlet close by. No AC line voltage wiring. No additional electrical box in the wall. No wall wart, batteries, solar panel, pedals or water wheel. The only wiring needed is the data cable back to the Ethernet switch and the local analog audio, making planning and installation much easier and much less expensive.
Rane's engineers have designed the NM 1 to have a redundant PoE supply along with the redundant data connections. It can be powered from either Ethernet port independent of which one carries the CobraNet data, so an independently redundant power system comes along with the redundant data system with no redundant effort. Switching between ports for PoE is almost seamless and audio interruption is minimal. If the primary port fails the secondary port takes over very quickly, typically 10 ms, without loss of programmed settings.
All parameters are controllable via standard SNMP messages including microphone gain and muting, amplifier output level and muting, and CobraNet Audio channel and Bundle assignments. Four exterior switches assign the NM 1 MIB's SysName variable to uniquely identify each unit on the network.
All NM 1 audio and data connectors are metal with locking, annular-ring shields for maximum durability, security and immunity from electromagnetic interference, be it radio, static or legislative hot airwaves. And all this fits in a very rugged (but good looking) extruded aluminum box.
The NM 1 is fully compatible with other existing CobraNet products.
Front Panel Detail
Click on the graphics for a close-up. Right-click to pan and zoom.
PoE Information
- poweroverethernet.com - Good place to start searching for anything PoE
- PowerDsine Midspans
- Cisco PoE products page
- 3Com Single Port
- 3Com Multiport
- D-Link Single Port
- D-Link Multiport
Further Information
