Yamaha MY16-CII 16-Channel Cobranet Network I/O Card (for Yamaha Digital Mixers)

The MY16-CII handles 16 channels of audio input and output that are assigned to bundles that will be transmitted and received to and from the appropriate network devices. The MY16-CII can use up to 4 output bundles and up to 8 input bundles.An audio networking system developed by Cirrus Logic, Inc. that allows real-time transmission and reception of uncompressed digital audio signals via a Fast Ethernet network cable.

The network can simultaneously handle up to 64 input and output channels, for a total of 128 channels (64 channels if repeater hubs are used). The maximum number of channels than can be handled in practical situations may be lower due to performance limitations imposed by the equipment used and the condition of the audio signal.

Currently, the CobraNet network will handle 16, 20, or 24-bit audio at sampling rates of 48 or 96 kHz. The CobraNet network is capable of transmitting control data at the same time as the audio signals. The types of control data transmitted are determined by the equipment used. The CobraNet network imposes a 5.33-millisecond (2.67 milliseconds or 1.33 milliseconds with some settings) latency on transferred audio signals. Latency and bit depth can be set via the CobraNet Manager application.

Bundles: Audio is transmitted over the CobraNet network in units known as “bundles.” These bundles are processed at the receiving end to reconstitute the original audio signals. In the case of the MY16-CII a bundle can contain up to eight channels. Each bundle is identified by a number from 1 to 65,279, and audio transmission via the network becomes possible when the same bundle number is specified at both the transmitting and receiving devices.

Multicast Bundles and Unicast Bundles: Two types of bundle can be used with CobraNet: “multicast” bundles and ‘‘unicast’’ bundles.Multicast bundles can be transmitted from a single device to all devices on the network, while unicast bundles are transferred from a single transmitting device to a single receiving device or a limited number of receiving devices.Unicast bundles are only sent to devices which have been set to the same bundle number as the transmitting device. Multicast bundles are sent to all devices on the network regardless of their settings, but only bundles with the specified bundle number(s) are processed.

Conductor and Performers: On any CobraNet network one device generates a timing signal that all other devices receive and are synchronized to. The device that generates the synchronization signal is known as the “conductor,” while all other devices are “performers.” CobraNet Cables and Hubs:Category-5 metal cables can be used for runs of up to 100 meters, while multimode optical fiber cables can be used for runs of up to 2 kilometers.“Cross” and “straight” Ethernet cables are available. “Cross” cables should be used for direct connection between two devices. Hubs and ‘‘straight’’ cables are required to connect 3 or more devices.