Department of Backstage and Infrastructure Management Introduction to Transmission Cables

XLR to XLR

The XLR connector is a style of , primarily found on professional audio, video, and stage lighting equipment. The connectors are circular in design and have 3 pins. XLR connectors are available in male and female versions in both cable and chassis mounting designs, a total of four styles. This is slightly unusual as many other connector designs omit one of the styles (typically a chassis mounting male connector). The female XLR connectors are designed to first connect pin 1 (the earth pin), before the other pins make contact, when a male XLR connector is inserted. With the ground connection established before the signal lines are connected, the insertion (and removal) of XLR connectors in live equipment is possible without picking up external signals (as it usually happens with, for example, RCA connectors). Three-pin XLR connectors are by far the most common style, and are an industry standard for balanced audio signals. The great majority of professional microphones use the XLR connector. In previous years, they were used for loudspeaker connections. Three-pin XLR connectors are used to interconnect powered speakers with line-level signals. This use is commonly seen PA system applications and seems to be growing more common.

Five to Five, Five to XLR(Male/Female)

This is actually a 6.5 mm connector but we, here at backstage, call it 5mm for ease of communication. This is a multipurpose cable. This type of cable is majorly used to connect electronic equipments to the mixer board e.g. synthesizer, guitar , etc. It is also used to connect various kind of sound processing devices to the mixer before the signal is actually sent to the speaker. Quality of transmission is better served by XLR than this although it is not obseravable. The picture to the left shows a 3.5 mm to 5 mm adapter. You can say that it is just an alternative to the XLR. If we talk about durability, it is more durable and easy to handle than XLR. Five to XLR, as the name suggests, is a cable with 5 mm connector at one end and XLR at the other. XLR can be male or female.

3.5 to XLR, 3.5 to 5

These are used to connect mobile/laptop to the mixer board. As we have discussed earlier there is no observable difference regarding quality of both the cables. VGA cable

Video Graphics Array is a 3 row 15 pin connector used to transmit video signals. VGA connectors and cables carry analog component RGBHV (red, green, blue, horizontal sync, vertical sync) video signals, and VESA Display Data Channel (VESA DDC) data. The VGA interface is not engineered to be hotpluggable (so that the user can connect or disconnect the output device while the host is running), although in practice this can be done and usually does not cause damage to the hardware or other problems. However, nothing in the design ensures that the ground pins make a connection first and break last, so hotplugging may introduce surges in signal lines which may or may not be adequately protected against. Also, depending on the hardware and software, detecting a monitor being connected might not work properly in all cases. We use this cable to project videos on the screen in auditorium or sometimes outside in the campus. Usually all laptops have a VGA port except Macintosh which has DVI () and HDMI (High Definition Multimedia Interface). We use DVI to VGA adapter or a HDMI cable to stream from a Mac.

HDMI cable High Definition Multimedia Interface is the modern and most sophisticated method of media transmission. It supports both audio and video signals which is absent in VGA. It transmits uncompressed video signals. HDMI is a digital replacement for existing analog video standards. All laptops and few mobiles have HDMI ports for media transmission. Latest HDMI 2.0 has 4K resolution support.

CAT5/CAT6 cable

This is the cable which is used in Ethernet(LAN). This is generally used for the purpose of networking among computers. We can also use this cable to transmit video signals with the help of a VGA to CAT5 convertor. CAT5 is also used to carry other signals such as telephony. CAT stands for category, CAT6 is faster than CAT5, besides this there is no difference in CAT5 and CAT6 cables. It has 4 pairs of twisted wires inside it, and yes they are twisted intentionally to reduce crosstalk between wires. Each of the four pairs in a Cat 5 cable has differing precise number of twists per metre to minimize crosstalk between the pairs. Although cable assemblies containing 4 pairs are common, Category 5 is not limited to 4 pairs. Backbone applications involve using up to 100 pairs. This use of balanced lines helps preserve a high signal-to-noise ratio despite interference from both external sources and crosstalk from other pairs.

Speakon connector

This is mostly used to connect amplifiers to speakers. A Speakon connector is designed with a locking system that may be designed for soldered or screw-type connections. Speakon connectors are designed to be unambiguous in their use in speaker cables. With jack and XLR connections, it is possible to use low-current shielded microphone or instrument cables in a high-current speaker application. Speakon cables are intended solely for use in high current audio applications. Speakon connectors lock into their sockets with a twisting motion, making them significantly less prone to disconnection than standard phone plugs.