Integrating Professional LTC Equipment Into Your Project

INTEGRATING PROFESSIONAL LTC EQUIPMENT INTO

YOUR PROJECT

In the last article, we dealt with the features of LTC timecode generation using external sound cards with balanced outputs and how this affects the reliability and quality of the transmitted signal.

Now let's talk about the equipment that was designed specifically to work with LTC digital timecode.

Below I will not give a list of all possible models that exist in our industry. From each class of devices, we will analyze the brightest representative, which will give us a complete understanding of the devices in each class.

Let me introduce you to the Brainstorm SR-112 Time Code Distripalyzer. This is a multifunctional device that works only with LTC signal.

The first function is a splitter. This device allows you to receive one LTC signal via XLR-female and digitally divide it into 12 outputs, of which two are XLR-male, two Jack 1/4 female and the other eight are transmitted via the DB-25 connector.

The pin out configuration is exactly the same as Tascam and Avid manufacturers. DB-25 male to 8 XLR male break-out cable can be purchased separately in stores.

Also, SR-112 allows you to individually adjust the signal level for each output.

The second function is the Reshaping Distorted Time Code. There are many reasons that can distort the LTC signal, the SR-112 allows you to correct the shape and level of the signal, to the native square form. Also in the settings of this device, we can set the parameters of the output LTC signal, thereby creating maximum compatibility between SR-112 and clients.

The third function is timecode generation. SR-112 has many options for how it can generate timecode.

It can start generating its own timecode, according to the parameters of the incoming signal, but after that, it is unlinked from the source. Also even if the LTC playback speed changes or the frames start jumping out of order, the SR-112 will still generate its own timecode until the LTC recovers or absence interval of timecode exceeded.

This is just one of five possible scenarios for generating and regenerating the timecode, which is possible on the SR-112. More information can be found in the manual.

The fourth useful feature is the timecode analysis. On the back panel of this device there is an Ethernet connector through which the SR-112 can be connected to the network. Through the network, it is possible not only to manage it, but also to view and export reports of the SR-112, where we can see when the timecode came, what mistakes were with it, when the regeneration began, and much, much more.

The next most frequently used devices, when working with timecode is Rosendahl mif4.

This is a universal timecode device which is designed to correct, analyze, convert and generate timecode through different physical interfaces.

Let's take a closer look at its capabilities and how it can be used during synchronization.

Its first feature is that mif4 can receive timecode via MIDI, LTC, USB and SDI interfaces.

When connected to a computer, mif4 is defined as the simplest midi device. Which can be used for software timecode generation or receiving. Due to this, mif4 can be used as a timecode widget for light and video consoles.

The second useful feature is the automatic conversion and generation of timecode to the output ports of the device. We can generate timecode via USB from a computer and this timecode will be relayed to MIDI and LTC outputs. It also works with other sources. If we receive a timecode on the LTC input, then mif4 retransmits it to the USB, MIDI and LTC output. If we submit a timecode to the MIDI input, the device will duplicate it on LTC, MIDI and USB.

The third advantage is the ability of mif4 to generate its own timecode for all outputs of the device. Generation parameters can be set manually, through the device control panel or using external MMC (MIDI Machine Control) messages.

The fourth feature is the analysis of the timecode and its playback speed. As we have already discussed in the previous article, the not constant and not original playback speed can also affect the quality of generation. mif4 shows such errors, which is very convenient when searching for mistakes in the timecode generation.

The fifth functional feature is the ability to correct a distorted signal. If the device receives an LTC signal that is too low or is distorted by induced interference, the client simply will not see the timecode. In such cases, it is sufficient to install mif4 between the receiving device and the LTC line, which is able to read the worst signal, correct it and give the client the normal LTC.

The diagram shows the simplest example of how you can use the mif4 system in your system to correct the signal and divide it into several clients.

Sometimes we have to work on projects where it is necessary to transmit a synchronisation signal over a fairly large distance, more than 30 meters, allowed by an analog balanced line. In this case, you must use additional equipment and data transmission technology.

We can use such sound data transfer protocols as DANTE, MADI or AVB, but then for this you need a separate sound engineer who can raise such a network and monitor it during the project.

Or you can use specialised technical solutions for this purpose.

For example, KISSBOX TC2TR. Fun fact, this was the first company that made support for the RTP-MIDI protocol in its technical solutions.

KISSBOX TC2TR allows you to convert LTC to MTC and transmit the signal using the RTP-MIDI protocol over the network.

In this case, we can either generate the timecode from the show server via RTP-MIDI to the network and receive it to the KISS-BOX controller, or use two KISSBOX devices in general to transmit or receive LTC, depending on whether you are using an Ethernet cable, optical fiber or WiFi, you can transmit your LTC signal over a distance of more than 200 kilometers.

Using the RTP-MIDI protocol, we can broadcast synchronisation protocols to several clients. This advantage also applies to KISSBOX equipment. Having one source, we can deliver the LTC signal to several clients at once.

In future articles we will surely touch on all the features of the RTP-MIDI protocol in more detail.

Now, when you think about integrating LTC into your future projects, you will have a complete idea of what equipment to use for this digital signal, and as a result, your knowledge and the level of you professionalism in shows will rise to a new level!