Frequently Asked Questions.
Below you can find answers to some common questions about OPTOCORE.
Which kind of redundancy is guaranteed from Optocore?
The Optocore network offers three different aspects of redundancy.
Fibre structure. Connecting the first device with a pair of fibres to the next and doing the same up to the last device, you enable the daisy chain, which is enough to run the system. To enable the redundant ring, it is sufficient to close the loop – connect the last device to the first one using an additional pair of fibres. Once the redundant loop is enabled, any connection can be lost (fibre or even device disconnection or break) without affecting the integrity of the network. In a matter of one sample time, the system will switch-over the redundant connection, without interruption of the data flow. As soon as the previously disconnected fibre will be available again, it can be reconnected “on-air”, with no need of network reboot or re-configuration by the user.
Power supplies. Every Optocore network device is equipped with dual redundant power supply, completely independent, with different power cables and automatic protection system (older devices are equipped with fuses). The automatic switch-over guarantees the continuity of the power supply of the unit in case of PSU failure. All the Optocore power supplies are 110-240 V tolerant, It means that they can be use worldwide without need to use any external PSU or any internal PSU upgrades.
Work Clock Recovery. In a digital synchronous network, one device is determined as Word Clock Master, all the other are slaves and accept the Word Clock distributed from the master. In case of failure of the Master device the complete network would be unlocked and unusable. This is not happening with the Optocore network because, if this problem occurs, the system reacts in a matter of one sample time, determining another working device as new Word Clock Master, recovering, with no interruption, the complete network functionality. In the very unlikely case of a double fibre disconnection, the former ring will be divided in two different networks, but, at least, the two independent rings will have a Word Clock Master each, working separately. As soon as one of the connections will be re-established, the system is recovering the work clock distribution, determining a single device as Master Word Clock, for the entire network. This Word Clock Management is automatically determined, not a single action is required by the user. The device having the lowest ID in the network is the Word Clock Master. It is possible to force a specific device to be the master even if it has not the lowest ID, by selecting a Master Clock priority flag in the device’s Local Detting. In case of multiple devices with priority flag set, the selection of the master will be done before between those devices, then between the others, selecting the one with the lowest ID.
For professional applications, should I use an external Word Clock Generator?
The Optocore network runs at 2Gbit/sec. Therefore the system word clock is 2Gbit and of a very high quality, extremely low jitter, to guarantee the synchronous and error free transmission. When the sample frequency of the audio is selected at the typical values of 48 (or 96) kHz, the clock for the internal A/D and D/A converters and for all the external devices is produced by a division of the 2Gbit system clock and distributed at any node. For this reason the quality of the word clock offered by the Optocore system is of the highest, since the already negligible jitter of the 2 Gbit clock is extremely reduced by this operation, when it is divided down to a 48 (or 96) kHz. For this reason, the Optocore Network should be preferred as word clock master, although it is possible to accept external word clock sources, via dedicated devices.
How to sync Optocore network to External Digital devices?
However Optocore recommend using Optocore network as a Word Clock distribution system, it is possible to sync it from external clock source. The only way to do that is to feed one of the devices with BNC and coaxial cable to WC IN. System will automatically recognize incoming clock and switch to that if device is set as a lowest ID or it has Master Priority Flag enable. It is not possible to sync Optocore network to incoming digital signals as AES/EBU or MADI.
Optocore is a synchronous network, which are the advantages?
Audio & video are synchronous signals, therefore the best way to transport it is via a synchronous network. The data and the clock are running together and all the devices connected to the network (Optocore and non Optocore) work with the same clock.
One of the biggest advantages of this style is the extremely low latency of the network. From any input to any output (digital to digital) that amount is only 0,042 ms. This is a fixed figure, not dependant on the signals path, hops, the number of the channels used, the length of the fibres. The latency value includes also the time necessary for a complete matrix.
Thanks to this design, the Word Clock is available at any node, from devices equipped with digital In & Out.
The theoretical advantages of the Asynchronous transmission (i.e. the re-transmission of lost data packages) are useless in real time situation, such the Live applications. You cannot stop the time – “The Show must go on!”
How many devices can I integrate in a one OPTOCORE network?
The number of devices connected by fiber is limited to 24 – there are 24 unique ID numbers in the main fibre ring. However the complete network integrates many more devices – each ID can be extended with additional seven SANE based devices with SANE1 port. Additionally port SANE2 can be used to connect up to eight Y3R-TP cards with MY-YGDAI slot for Yamaha consoles. This enables the total number of 384 Optocore devices in one network.
What is it SANE?
SANE is a synchronous protocol used to transport audio over CAT cables created by Optocore. SANE stands for Synchronous Audio and Ethernet. The same SANE cable connection carries audio and Ethernet signals, but synchronous audio is completely independent of asynchronous Ethernet. SANE enables transport of 64 bi-directional audio channels and 100Mbit Ethernet through a standard Cat5 cable. It is possible to daisy chain SANE TP devices with the main FX Optocore unit; each node in SANE daisy chain can be 100m apart.
What is the difference between FX and TP device?
Each device, which is marked as a FX (fiber optics), can operate in a fibre Optocore ring. TP (twisted pair) devices can be connected to any FX device over Cat5 cable. FX devices utilise Optocore fiber protocol while TP devices utilise SANE Cat5 protocol.
All FX devices are equipped with a common Main FX Board which features:
- 2 x fiber Optocore links on SFP
- 2 x Cat5 SANE links
- 2 x LAN ports
- 4 x RS485
- Word Clock IN and OUT
All TP devices are equipped with a common Main TP Board which features:
- 2 x SANE links
- 1 x LAN port
- 16 x AES/EBU pairs on two DB25 connectors
- Word Clock IN and OUT
Which kind of network topology can use with Optocore? Star? Ring? Mixed?
Optocore concept is based on a ring, however it is very simple to build different network topologies. Optocore can be used in the following topologies: redundant or non-redundant point-to-point, daisy chain, redundant ring, redundant star (with the passive fiber patchbay in the center or with active Route66 by BroaMan – www.broaman.com) or mixed.
The ring structure offers multiple advantages. Once a signal is accepted in the network from any point, it is available for output there and at any other point, with no bottle-neck in the data availability. Thanks to the ring approach Optocore reduces the problem of main device failure – each device in the ring is equal and each device carries the complete matrix. The closing of the loop offers the complete redundancy with the smallest fibre count – very important for mobile application. Example: N devices connected in a redundant ring require N fibres. The same amount of devices (N) connected in a redundant star network topology, would require 2N-2 fibres, almost doubled amount.
Is Optocore using a standard fiber protocol? Which kind of data can be transported? How many channels?
The protocol used by Optocore is proprietary. The 2 Gbit bandwidth allows the transmission of up to 1024 audio channels with sample frequency of 48 kHz (512 @ 96 kHz) by means of a single duplex fibre optic cable. That bandwidth can be shared and utilized for the transmission of other signals as well, such as video and data. The Dynamic Input Allocation allows the user to customize the kind and the number of signals of its network, always respecting the limit of the bandwidth. It’s important to underline that only the number of the inputs does matter for this calculation. Outputs do not use “space on the fibre” and once a signal is present in the network, it can be routed to output, as many times as the user wants. For example a stagebox, that consists of 3 x X6R devices (X6P-FX-16MI, X6P-TP-16MI, X6P-TP-16LO) with 32 Mic level Inputs and 16 Line level outputs, uses only 32 channels of the protocol (of the 1024 available) and not 48, as one may think.
Is it possible to transport Ethernet as well?
Yes, each device is equipped with LAN ports. Each device is equipped with 2 (FX type devices) or 1 (TP type devices) standard LAN RJ45 ports and two additional SANE ports which can be also used for Fast Ethernet operations. All devices in the network create automatically a big unmanaged switch – as if all devices connected were in the same box in the same network, even when they are really hundreds or thousands of meters away.
In addition the devices extend your LAN far beyond the technical limits of the traditional Ethernet. The devices feature fully IEEE 802 compatible 10/100Mbit Ethernet ports, but enhance it by redundant power supplies and a guaranteed fibre redundancy without difficult Ethernet setups like Spanning Tree.
Don’t get confused: Optocore IS NOT USING Ethernet for the audio distribution, but allows the “tunnelling” of it via the fast, synchronous, redundant fibre optical network, together with all the other data.
Which are the best optical connectors for fixed and mobile applications?
The optical interfaces of the LC-type UPC, equipping all the Optocore network devices, are absolutely reliable for fixed installations and indoor use besides MADI connectors, which are SC-type with the same feature as LC connectors.
The light data exchange is guaranteed by the mechanical alignment of the connectors, as shown in the image below.
For more rugged applications e.g. mobile usage, the Expanded Beam connectors mounted on 1U panels are available, along with matching inter-connection rugged cables transported on cable drums.
The Expanded Beam technology ensures maximum safety in optical data exchange, by coupling beam expander & beam focusing lenses to enlarge the contact surfaces. This method is perfect for digital transmission where the optical budget loss of this kind of connectors is not critical and very well compensated by the highest reliability of the light’s communication. Dust or moisture cannot interrupt completely the light flow between OptoCon connectors. They can also easily be cleaned on the road.
Since the plugs of OptoCons are of the hermaphroditic type, a drum cable can be extended by simply connecting the next one, without any additional plugs coupler.
Why has OPTOCORE just a maximum of +18dBu input level, as +24dBu are generally preferred for long distance cables?
The reason for that is that OPTOCORE utilizes a digital transmission method, completely different from the analog style. This means that even for long distances there is no signal loss and due to the interference-free behavior of the fiber the signal arrives to the destination point undistorted, clean and with the same level of the origin. Since with 18dBu any analog input (Power amplifiers, Analog consoles, Recorders, PA management systems) can be fully driven, there is no reason to accept higher signals inputs.
Do I need special extension plugs to connect more than one optical cable drum?
No, the OPTOCORE military connectors are hermaphroditic, this means that you can connect a cable plug directly to the next one.
Is the quality of the sound depending on the number of the channels you are using?
No, not at all. The protocol that OPTOCORE transports is fixed and transmitted entirely. The amount of data will not change with the real amount of audio channels connected in input or output.
Can I use my traditional intercom system via OPTOCORE?
Full audio and data transmission is possible with intercom systems from our technical partners as Clear-Com, RTS. We also provide special hardware version for AES/EBU based intercom systems (Clear-Com, Riedel).
Intercom systems can be fully integrated with a standard Optocore network.
Does the system depend of the external computer and Windows OS?
No, the external software is just a big remote control. If you disconnect the computer when the system is running, you simply let it work with the latest configuration you have set.
However a startup configuration need to be done using Windows based computer.
Can you use analog and digital consoles at the same time, in the same network?
Yes, you can have up to 24 different network devices in the same optical ring. Up to four Emulation Modes can be enabled in the same time for different console manufacturers:
Digital consoles can be connected with a Optocore network using digital signals as MADI (DD2FR-FX, DD4MR-FX), AES/EBU (DD32R-FX), purpose build interfaces as MY-YGDAI cards for Yamaha or directly with Optical Optocore signal (DiGiCo).
Which is the system latency? Is that fix or depending on the amount of data in the network?
The intrinsic signal delay of an OPTOCORE channel through the fibre is extremely small and is dominated by the necessary converting times. All data streams transmitted through similar channel types will appear at all outputs on a network at the same time. Transmission delay is negligible amounting to less than 200ns for each unit attached to the network. Beside the delay caused by the finite light-speed on a fibre, which must be taken in account with very long distance transmission, there is no notable summing of delay throughout the units in the OPTOCORE network.
The processing of AD converted audio signals causes typically a delay of 39/FS and the processing of DA converted audio signals causes typically a delay of 28/FS (FS = sample frequency). For synchronisation purposes and data re-arrangement another maximum of 2/FS needs to be calculated. The result is a delay of only 69/FS from “analog to digital to light to digital and back to analog”, which calculates to a maximum of 1.44ms @ FS=48kHz and 0.72ms @ FS=96kHz. Thus the processing of already converted audio signals as with the DD32R-FX, causes the above mentioned maximum delay of 2/FS, which calculates to a maximum of 42µs @ FS=48kHz and 21µs @ FS=96kHz.
Can I install the Optocore Control software on my Mac?
There is no software control for Mac OS, but we tested the OPTOCORE Windows software with Virtual PC (for MAC) and it runs perfectly.
Which Windows version are compatible with a Optocore Control Software?
All Windows version up to Windows 11 are compatible with the Optocore Control Software.
Is the level of the OPTOCORE microphone pre-amplifier direct controllable and recallable from my Yamaha Digital console? What about other brands console?
This is possible from Yamaha console via the Yamaha Emulation Mode of the Optocore devices. It emulates the presence of Yamaha AD8HR’s to let you control the gain and phantom via the Remote port of the Yamaha console. This remote signal is transmitted by means of a couple of RS485 ports of the DD32R-FX device, YG2 or Y3R-TP.
DiGiCo consoles use native Optocore protocol for control which means they can fully control OPTOCORE devices directly and can be integrated with them in one network without any special setup.
Direct control is also possible for below listed manufacturer’s console:
Can I integrate my older Optocore devices with R-series devices?
Yes, all Optocore devices are backwards compatible with older units (the only exception is the first revision of DD32 unit).
Older devices as E-series or LX4A, LX4B, YG2, YS2 feature a hardware limitation of 1 Gbit fiber speed. To integrate older devices with R-series the latest possible firmware and software version to use is 2.14.019.
R-series devices can work in both fibre speeds 1 Gbit and 2 Gbit what is configurable in the software. R-series’ software and firmware is being improved constantly to increase Optocore system features and flexibility.
R-Series devices are recommended if you wish to take advantage of the latest software improvements.
Is it possible to lock Optocore network to video Bi-level/Tri-level sync?
Yes, it is possible to lock the complete Optocore network to the video sync.
The easiest and recommended way to achieve that is to use Mux22 device from BroaMan (www.broadcastmanufactur.com/index.php/mux22/overview). It is equipped with Optocore FX board and special VSync board, which provides selectable sync I/O – Bi-Level (PAL/NTSC), Tri-Level or Word Clock.
When Mux22 is Optocore’s Word Clock Master, the complete network will sync to the external video source. Furthermore, all Optocore devices will output Word Clock, which is in sync with the video.
Optocore is a perfect fit to provide sync conversion and distribution.