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Future Proof Your Network

Future Proof Your Network

Category cables have been in use for a number of years. Most consumers will know these as network cables, Ethernet cables, or possibly even Cat-5 cables. However, they may not understand what Cat-5 means or how to determine if that is really the cable in use. Category cables have been upgraded multiple times and the vast majority of consumers are probably using Category 5e cable in their home networks. As our networking needs have increased, so have the cables, and a change is already underway to go beyond Cat-5e.

Category cables are designed to transfer data within networks. They are the standard method of connectivity for Ethernet networking. Cat-5e is still the most common cable but it is close to its limits. In fact, larger networks requiring higher bandwidth and better interference protection have already abandoned 5e. We are demanding more from our networks, transferring more data at faster speeds than ever before. In addition to Ethernet networking, category cables can now be used for audio and video networks. Dante audio networks transfer uncompressed multi-channel audio via category cables and HDBase-T promises to be the future of home audio and video integration. HDBase-T transmits high-definition audio and video, Ethernet, device control signals, USB data, and power all through one category cable. Category 5 cables cannot handle this much data.

In order to meet the bandwidth needs of newer networks, we must use Category 6 cable. Category 6 improves bandwidth and crosstalk protection over previous generations of category cable. It has been tested to perform up to 250 MHz and can transmit 10 Gigabits per second (Gbps) for up to 55 meters. This is not to say it cannot go beyond these points, only that this is how the cable was tested. Category 6 cables also have several shielding options. You can purchase cables in the more traditional Unshielded Twisted Pair (UTP) construction, or with shielding around each twisted pair, the full cable assembly, or both. Hosa’s CAT-600BK series is an example of Category 6 cable with both shielding around each twisted pair and around the entire assembly.

In addition to the original Category 6 cable, a revision to the standard later added Cat-6A cable, also known as Category 6 Augmented. This cable provides even better protection against crosstalk and has been tested up to 500 MHz. Cat-6A can run 10 Gbps Ethernet up to 100 meters.

It’s important to note that while Cat-5e was the updated version of the original Category 5 standard, there is no Cat-6e version recognized by ANSI/TIA.

The good thing about category cables is that they are backward compatible. If you are setting up a new network, it is a good idea to use Cat-6 cable even if you do not believe your network will need the added bandwidth. Taking that step now should make things easier in the future.

- Jose

How to Properly Connect the DB-25 Jack on Your Audio Device

Many times, people look at the jacks on the back of a device to figure out what cables they will need. While this is not really the best way to figure things out, most of the time it will get results. If you see an RCA jack and ask for an “RCA cable”, you’ll probably find a suitable cable (though there are different types of cables that use the RCA connector). But if you don’t get a little more information, you’ll most likely run into trouble when you see a DB-25 jack on the back of your audio device.

DB-25, or D-sub, connectors were originally created for computer applications. The audio industry adopted the DB-25 as a way of getting multiple channels in and out of devices while taking up minimal space. In this regard, the DB-25 connector works great. However, the use of this connector is problematic because there is not one universally accepted way of wiring it. In fact, there are three widely used wiring conventions when it comes to DB-25 in the audio world.

Some devices use D-sub connectors as a way of inputting or outputting eight channels of balanced analog audio. Each balanced channel requires three pins—one for the positive signal, one for the negative, and one for the shield—and each channel is grouped in a triangle pattern by taking two pins from one row and one pin from the other. Eight channels require 24 pins and pin 13 is simply not used. The Hosa DTM-800 series balanced snake is wired this way. It connects to the DB-25 output and breaks out to eight XLR male connectors. The Precision 8 mic preamp by True Systems uses a DB-25 connector to output all eight channels. This makes it possible to run a single cable with eight channels to an audio interface or mixer.

Professional audio devices can also use one DB-25 connector for eight channels In & Out (I/O) using the AES3, or AES/EBU, format. This digital audio format enables devices to send two channels of audio along one balanced audio line. This is where it really gets fun, as there are two standards for AES/EBU multi-channel I/O—and manufacturers choose which one to use.

The first is known as the Tascam wiring standard. The Tascam wiring standard is the same as the analog standard at the DB-25 connector end. The wire, however, must be different, as it is not passing analog sound. The AES3 specification requires 110-ohm balanced cabling for AES/EBU signals. Unlike analog snakes, AES/EBU snakes carry two digital channels on each balanced line. This means through one DB-25 snake, the device can send eight channels and receive eight channels simultaneously. If you are using a digital snake that breaks out to XLR connectors, it will have four male and four female XLR connectors instead of four like connectors on the analog snakes. Avid and Universal Audio are two companies using the Tascam standard. Avid’s ProTools HD I/O uses AES/EBU via a DB-25 jack.

Companies such as Apogee and Mackie, among others, have adopted the Yamaha wiring standard for their AES/EBU I/O. The wire is the same as that used for the Tascam digital snakes but the pin configuration is much different. In this case, the ground wires are on one side of the connector, while the other side gets the conductors. The Lynx Aurora 16 AD/DA converter uses AES/EBU with the Yamaha standard.

Note that if you are connecting two digital devices, you must make sure to use the correct pinout for each. If one of your devices uses the Tascam standard for its AES/EBU I/O and the other uses the Yamaha standard, you can still use them together. You must, however, use a snake with the Tascam pinout on one end and the Yamaha pinout on the other. Analog to digital is not as simple. You cannot use a DB25 snake to interconnect AES/EBU and analog signals. This would require a separate interface, which is a topic for another discussion.

The next time you turn to the back of your device for cable answers, remember the connector type is not everything—especially with DB-25. Your first question should be whether you’re looking at an analog or digital connection. If it’s digital, the next step is to figure out the wiring standard the device uses. Taking these steps will decrease headaches down the road and ensure you purchase the right DB-25 snake the first time.

- Jose