Next Generation Audio

“Agility and flexibility” are the mantra of the new broadcast paradigm. Audio has always been the trailblazer for new technology, it was first to go IP and first to provide software solutions. But where is the next generation of audio taking us?

Broadcasters are chomping at the bit to take advantage of the new opportunities IP and software solutions have to offer. The traditional Capex models will still be with us for some time to come as they have a place to play in core infrastructure design. But new business models based on pay-as-you-go solutions are getting closer, and broadcasters are driving vendors hard to deliver.

Science Meets Art

Audio is unique as the demarcation line between science and art has been blurred for as long as people have been reproducing sound. Whether a 7th century Byzantine organ or a 21st century AI composition, the crossover and the influences each has on the other is far from clear. Primarily, this is due to the way we experience sound.

Turning sound waves into electrical stimuli for the brain to interpret is only part of our experience. The sound waves act as a stimulus to draw on deep emotions embedded in the human mind. They draw on our own memories of happiness, anger, and passion. Consequently, audio is never experienced by two people identically.

Monitoring Experiences Differ

And if no two people experience audio identically then it’s not unreasonable to expect no two people should be expected to monitor sound in the same way. Up to recently, the rigid form factor of hardware products has imposed standard working practices on creatives and technologists alike. This is partly due to the physics of the design limitations, but more significantly due to the cost and time taken to redesign products.

A typical design cycle for a new audio product could easily take twelve months, and that’s if the design process progresses well.

Software based solutions have the potential to release manufacturers and hence broadcasters from the shackles of these historic working practices. But as with most of the advance’s technology has given us, human nature often dictates that we take small safe progressive steps instead of huge risky leaps.

Small Safe Steps

It is possible to take a giant leap from hardware bespoke designs straight into COTS software monitoring running on x86-type servers. But over tens of years of experience and evolution, broadcasters have learned that they must be able to trust their monitoring. This is truer now than ever, especially as more and more audio processing algorithms are available for COTS platforms.

Few broadcasters can completely build a greenfield IP installation. Instead, they move piecemeal from their SDI, AES and MADI systems to IP installations. They may even maintain these hybrid systems for many years. Having systems that can reliably monitor both IP and traditional infrastructures as they progress forward.

Figure 1 – The Agile software development method empowers manufacturers to bring features to market in the fastest time possible. Typically, plan, build, and launch cycles total two weeks to a month to deliver features quickly for client evaluation.

Figure 1 – The Agile software development method empowers manufacturers to bring features to market in the fastest time possible. Typically, plan, build, and launch cycles total two weeks to a month to deliver features quickly for client evaluation.

This leads to the next development in broadcast sound; hybrid-agile monitoring. This flexible approach provides the best of both worlds for broadcasters and manufacturers; a dedicated hardware platform with installable software modules to improve flexibility and agility.

Reliable Monitoring is Essential

The technology to monitor on a COTS platform does exist and it is possible to do. We may even monitor on a COTS platform in the future. But as we migrate to IP, or even stay with SDI, AES, and MADI, broadcasters must be sure their monitoring platforms are solid and reliable. There is a plethora of SDI, AES, and MADI PCI-type interface cards currently available to facilitate COTS solutions. But installing them detracts from the true benefits of using off-the-shelf servers. It also limits public cloud options and with the current state of technology, it’s often safer to use hybrid-agile monitoring.

Embedded designs offer the most reliable hardware. SDI, AES, and MADI chipsets facilitate direct connection to FPGA’s (Field Programmable Gate Arrays) to deliver very low latency processing (in the order of a few microseconds). Furthermore, FPGA’s have DSP’s and microprocessors directly available on the silicon, thus improving processing efficiency and speed.

Optimized Operating Systems

Although embedded systems don’t dispense with operating systems, the versions they offer are highly optimized and incredibly reliable. Heartbeat and watchdog monitoring further adds to their dependability. Their low power consumption generates little heat and reduced size makes them easy to install in operational areas.

COTS platforms tend to offer general solutions. An x86 processing platform running in isolation could be optimized for audio by using a bespoke operating system. But this would render the design useless for virtualization and hence negate many of the advantages COTS has to offer.

Figure 2 – Embedded FPGA hybrid-agile hardware platforms are ideally suited to broadcast applications as their behavior is highly predictable.

Figure 2 – Embedded FPGA hybrid-agile hardware platforms are ideally suited to broadcast applications as their behavior is highly predictable.

Virtualization requires a software control application running directly on the hardware, this governs access to the IO including the PCI interface to the SDI, AES, or MADI connectivity. Blocking can occur as the virtualization software prioritizes access resulting in potential latency and delay. Strategies and solutions are available to reduce this using method such as kernel bypass and DPDK (Data Plane Development Kit), but they add significant complexity to a system.

Virtualization for real-time applications is still a developing technology and only just finding its way into broadcast television. At least during the transition and migration phase, broadcasters need to have some constants they can rely on. Hybrid-agile hardware platforms are a development on a theme, a small safe step, as opposed to a giant risky leap. They provide the constants needed for monitoring highly complex broadcast infrastructures.

Software Modules Improve Flexibility

As more vendors move to software processing, availability of soft-modules is becoming more prevalent. A hybrid-agile hardware platform could be shipped with a basic operational configuration as part of its design. That is, it might have basic SDI ancillary audio monitoring, with AES and MADI decoding.

Adding extra features such as Dolby Atmos or Loudness monitoring is easily achievable. These software modules can be permanently installed and even enabled and disabled as a user demand. An integrated automation system may even be able to procure, install, and enable software modules from the front panel.

There are many licensing options and strategies available. From time-enabled to hardware-specific, users can enable and unlock features as their business use-case demands. This pay-as-you-go model greatly improves a broadcaster’s flexibility and agility.

Intelligent Automation

Authorization frameworks such as OAUTH2 enable other applications to gain limited access to the platform through API’s. This opens the door wide open for highly intelligent automation systems that can configure monitoring platforms. Sound engineers may even be able to create their own bespoke monitoring profiles that they load when they start their shift.

Agile-hardware platforms combined with software-module licensing opens a world of opportunity for broadcasters. New workflows can be provided. And business models more suited to the demands of the production team came be better facilitated.

Interoperability is critical for broadcasters and many are driving vendors hard to achieve this, especially with SMPTE’s ST2110 standard. The industry collaboration group AMWA (Advanced Media Workflow Association) is pushing forward NMOS (Network Media Open Specifications) to deliver a suite of specifications to enable vendors to operate seamlessly together.

Flexibility is Key

SDI, AES, and MADI are interoperable by default. An output from an SDI matrix from one manufacturer directly to the SDI input of a monitoring device will work. The same is true of AES and MADI. Although these standards are rigid, they do lack flexibility, hence the reason many broadcasters are moving to IP.

Consequently, during the migration phase, hybrid-agile hardware options deliver the most optimum solutions. Vendors can design, implement, and install software-modules with incredible speed and consistency. The pay-as-you-go model also helps vendors as they can react to client demands faster and be able to cost effectively test the market with new features and options.

As we progress to the next audio formats, whether this is immersive or object audio, improved surround sound or higher sample rates, the hybrid-agile hardware platform is best suited to meet the demands of the next generation of audio. And this isn’t just about sound, it’s also about the business model and how vendors can help broadcaster’s transition to IP.

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