The challenge of systems integration
Apr 1, 2002 12:00 PM, By Mark Krieger, CBT
Like so many other facets of the broadcast industry, the role of the contract engineer continues to evolve around technological advancement. One has only to look back 20 years or so to recall a time when computers of any type were likely to be found only in a radio station’s sales or business departments. In those days, technical upgrades to the broadcast facility were likely to appear as a new piece of equipment that was simply plugged in to an outlet and wired into the audio chain using XLR audio connectors or barrier strips. Today’s realities are different. Now the issue is not so much where to put the new box, but how to best integrate the new �solution.� Instead of pondering simple questions like balanced or unbalanced audio and remote control requirements, engineers now face multiple issues when introducing new types of digital audio systems into the broadcast environment.
Integration at the hardware level is the first step.
There are three major areas of concern when it comes to integrating new hardware/software platforms into an existing facility. The first is connectivity at the hardware level. Most studio and production tools are available with both digital and analog I/O, but interfacing them is sometimes problematic. While AES and SPDIF digital inputs are more or less the standard interchange, consumer-oriented equipment with optical interfaces is also encountered. The picture gets even more complicated when considering sample rates. Existing AES equipment usually employs 48kHz, while CD players most commonly employ 44.1kHz. If you’re connecting everything through a digital console with selectable input types and sample rates, great. Yet the equipment or the desired configuration often doesn’t allow for this, and where dissimilar digital I/Os meet, interface and sample-rate converters are required. Because the cost of these black boxes adds up and sample-rate conversions are to be avoided whenever possible, you need to pay close attention from the start. Switching of inputs, outputs and studios may also require digital routers and a master reference (synch) clock.
Achieving connectivity at the network level can also be a challenge. For example, many popular PC- and Mac-based production packages can communicate at the network level, but careful attention must be paid to what network topologies are in use. Some older equipment was designed around thin Ethernet, while 10baseT and 100baseT later became popular, though economics frequently dictate that systems of these differing vintages must be adapted to communicate with one another. Likewise, many popular on-air digital delivery systems claim to be compatible with existing traffic and accounting systems – but beware: If more than one vendor is involved, getting this to work in practice is seldom as easy at it sounds. If your IT skills are not quite up to snuff, you may need some help sorting out cost-effective ways of tying various platforms together.
The final factors in this equation are the digital storage mediums and sound file topologies themselves. While CD burners have made direct audio archiving easy and inexpensive, it has to be done at 44.1kHz and in compliance with �orange book� standards. More often then not, however, it is necessary to store complex production projects, news actualities, and even music, as mass-stored data. As a result, the engineer has to deal with the complex issue of sound file interchangeability. Unfortunately, the PC world is still stuck with the nebulous WAV format, with its variable word length and sample rates. Further complications arise from the potpourri of compression algorithms currently in use, a factor that sometimes results in their haphazard overlap. So far, we’ve only mentioned the inside of the studio facility, but digital STL and transmission chains are also considerations, particularly in respect to sampling rate. Ditto for remote broadcasts and feeds, including satellite and codecs, which all employ some form of digital compression. The situation is greatly exacerbated by the reliance on LANs, WANs, and the Internet by broadcasters, which sometimes results in digital sound files being copied (and converted) dozens of times.
Differences in protocols, topologies and data formats all must be considered when mixing various systems.
Unfortunately, a lack of sophistication and awareness regarding the negative side effects of compression overlay and file/sample rate conversion is prevalent in the radio industry, and sometimes results in an inferior on-air product. Thus, it ultimately falls to the engineer to see that the quality, productivity and flexibility of any new system are optimally balanced.
This can be done in three phases. First, you must be proactive in understanding your client’s needs and expectations before the selection and purchase of new hardware and software. Don’t be afraid to speak up if you realize that another product or approach will better accomplish a specific task. This requires fully educating yourself about the systems in consideration as well as the mission of those expected to use them.
Second, take the time to thoroughly read and understand the nuances of the system or application before you install it. Because time is money and today’s broadcast hardware and software are complex, this is an area where one may be tempted to cut corners. Often, the documentation supplied lacks the detail necessary to achieve the best results, and thus requires additional research on your part Nonetheless, it’s an essential step.
Finally, put together a training plan that not only trains key personnel as users, but also increases their ability to make decisions that will enhance, not degrade, the final product.
The role of today’s contract engineer has indeed changed. Even so, we can effectively deal with the challenges accompanying that evolution by embracing a comprehensive approach to system integration.
Krieger, BE Radio’s consultant on contract engineering, is based in Cleveland and can be reached at[email protected].