When enjoying a television programme, audio represents half of the overall viewing experience and therefore, it must be right. To ensure the optimal experience for the customer, the broadcaster must be able to monitor not only audio and video presence with ease, but associated metadata, as well. Until recently, the majority of audio monitoring solutions […]
When enjoying a television programme, audio represents half of the overall viewing experience and therefore, it must be right. To ensure the optimal experience for the customer, the broadcaster must be able to monitor not only audio and video presence with ease, but associated metadata, as well.
Until recently, the majority of audio monitoring solutions simply served as monitoring speakers with level meters. These meters, along with phase indicators, gave operators a general assurance that the audio signal was there, and was more or less the right level, even if that meant that the end result could be a less than optimal viewing experience for the modern consumer. Ever increasing numbers of consumers are listening to television programmes more and more critically in home theatres with very high-quality surround sound systems.
Fortunately, with the move to digital video and digital processing systems with multi-channel surround sound, incoming content streams include a significant amount of audio metadata and thus provide broadcasters with the means to monitor and measure audio in much finer detail and far more effectively. As a result, the engineer within a digital broadcast facility can become much better equipped to maintain or improve the quality of the on-air product.
As the metadata transmitted along with the audio and video content within the broadcast stream indicates the integrity of the stream and signal, the proper handling of this information by the audio monitoring system in place is essential. Todays monitoring systems can monitor not only Dolby Digital metadata, but also a wide variety of critical SMPTE-2020 metadata within the incoming stream, as well as video format and other system information.
This high volume of information can be overwhelming, and the operator typically needs only a fraction of it to actually troubleshoot any audio issues. However, for any two users or applications, the significance of different types of data likely will vary, so current audio monitors with flexible metadata-handling can allow operators to configure the system to display key data on its front-panel screen according to relative importance. Thus, the operator can group sets of information by screen and simply flip through those screens (and data sets) in order to identify potential audio errors and determine their source.
With this capability, the operator can quickly determine the status of the signal if audio channels are in the right place, if channels have been swapped or are out of phase, or even if there is a buzz in a mic pickup. Loud, clear audio monitoring and fast access to on-screen data enable the operator to spot those and other audio issues obvious or not as they occur, and possibly fix the issue in a short amount of time, before the viewer grows impatient and changes the channel. Without consistent monitoring and ongoing flagging of potential problems, serious errors such as a missing channel can go unreported and unresolved.
The audio monitoring system can help to identify basic as well as more complex problems, such as audio loudness, that also can detract from the viewer experience. With, for example, standards-based loudness measurements being taken continually and the histogram logged over time, the modern audio monitor allows operators to identify issues that they may not have seen happen in real time. In this case, evidence of loudness lapses can be documented and even automatically emailed to one or more staff members for review. Suppliers of programme material can then be flagged to exert better control over their programme material.
The well-designed monitoring system makes it easy for the busy operator to view key parameters at a glance. In production trucks and facilities in which rack space is at a premium, its important to get as much technology as possible into that small space. Even more important is putting not just information, but convenient functionality in front of operators. A range of functions and presets on the audio monitoring unit can enable the user working in a fast-paced live environment to drill down to the source of an issue quickly with just a button press and the turn of a knob.
As broadcasters needs change, card-based audio monitoring and processing systems offer them a cost-effective way to adapt without having to purchase new monitors all over again. Apart from supporting monitoring functions, they can provide signal processing tools and even features such as full digital mixers, integrated into just one unit to facilitate mixing and swapping of channels from the same interface. Such solutions make a smart investment, as they can be configured and repurposed for a variety of applications across a facility or organisation. With this flexibility, modular card-based audio monitors have become long-lived solutions capable of serving users changing monitoring needs.
The incorporation of greater processing capabilities and functionality into single audio monitoring solutions also has allowed broadcasters to reduce discrete system requirements and simplify their overall workflows, infrastructures, and operations. However, dedicated systems that meet very specific needs continue to play a valuable role in audio monitoring operations.
For example, standalone loudness monitoring systems that measure, record, and display key loudness parameters are useful tools that can be applied throughout the facility to ensure compliance with loudness standards. Simple and cost-effective, these solutions verify compliance with little or no user intervention. Likewise, straightforward SDI audio monitors enable cost-effective high-performance monitoring of embedded audio in 3G/HD or SD-SDI streams when SDI is the facility standard.
Whether the audio monitoring system is a full-featured system with robust signal processing capabilities or a standalone solution for narrower monitoring needs, convenience is essential. Todays monitoring systems make it easy for operators to have confidence in their signal. While engineers have many responsibilities in addition to audio monitoring, they need to know that the signal that reaches audiences will meet the viewers expectations.
John Giordano currently serves as Director of Engineering at Wohler.
