HDMI 2.1a, USB4 Version 2 and Wi-Fi 7 are among the major new connectivity specs entering the pro AV market. Tim Kridel explores their capabilities and use cases.
The original official Swiss Army knife from 1891 had a blade, reamer, can opener and screwdriver. Over the decades, it’s swelled in both girth and purpose with the addition of tools such as scissors, fish scalers, hoof cleaners and even butane lighters.
The modern enterprise equivalent is the dock, with ports such as USB-A, USB-C, HDMI, Ethernet and DisplayPort, to name just a few commonly found standards. Like the Swiss Army knife, the dock in the classroom, conference room or office is there to cover as many scenarios as possible.
“The reality is that today, everything we do is with computers, especially since Covid,” says Ken Eagle, Hall Technologies vice president of technology. “We're doing so many remote meetings, even in classrooms, and consumer devices are becoming part of the meeting. That means my iPhone, tablet, laptop or any device that I bring into the meeting, I really want some way to allow that to interact with the conversation I'm having with both the local people and the remote people.”
This preference includes the bring your own device or media (BYOD/BYOM) trend, such as college students making multimedia presentations. Chances are good that it will be over USB — and even more so in the future, thanks to an EU ruling that requires USB-C in “radio equipment” — which includes BYOD gear such as iPhones and iPads — by December 28, 2024.
“USB has really become the method to let all these different devices talk to each other,” Eagle says. “That's tricky in itself because USB has a number of different versions.”
There are also issues that lurk behind the USB connector.
“I have a switch with a USB-C connector,” says Bernd Schindler, an AV and IT consultant. “It uses a DisplayLink chip, so you need a driver and software for it on your laptop, while the other USB-C connections from a user's perspective are completely the same and use DisplayPort out mode. Some devices only support the one. Some devices only support the other. So it's really hurting usability.”
Many of Schindler’s corporate clients have a mobile-first policy, where employees are issued laptops.
“Most of the docking stations, no matter if they are Dell or Lenovo or HP, use the DisplayLink driver,” Schindler says. “They only use it in their conference rooms because that's convenient. They put a docking station in front of the HDMI cable, and then the next time a guest comes in and plugs in their laptop, it won't work [even though] it's USB-C.”
USB4 V2.0: More bandwidth and power, less fragmentation
The latest version — published in October 2022 — is as much about addressing at least some of the fragmentation as it is about increasing capabilities.
“USB4 Version 2 defines delivering up to 80 Gbps over our current USB Type C cables and connectors,” says Jeff Ravencraft, USB Implementers Forum (USB-IF) president and COO. “For certain apps like displays, they might want to take advantage of an advanced feature where we can deliver 120 Gbps through reconfiguring the lanes over the USB Type C interface.”
Some pro AV vendors like what they see.
“We’re keeping tabs on USB4 Version 2.0, which brings with it massive bandwidths,” says Stijn Ooms, Crestron director of product strategy AV and digital workplace, Europe. “Additionally, USB4 Version 2.0 features asymmetric data transfer, meaning 120 Gbps output from the host and 40 Gbps return from the device to the host, making it useful in many scenarios where asymmetric data transfer is required, such as display + docking station, 80 Gbps for display output and 40 Gbps for data transfer.”
Power is both another major upgrade — to 240 W — and an example of where the USB-IF is addressing some of the fragmentation concerns. For example, there are now five port logos that indicate the data rate.
“For certified cables, we're now requiring that the cable has to be properly marked to make it easy for consumers to understand at least the data performance and the power capability,” Ravencraft says. “The goal was to really help consumers clearly identify the performance and power capabilities of any certified USB solution. We’ve moved away from trying to use our logos to represent to the consumer any given USB specification, revision level, or underlying technology, [such as] USB 3.2.”
Some pro AV vendors think this will provide clarity.
“USB4 is interesting in that it provides a better and more standard method for defining video and power over the USB interface,” says Steve Metzger, ZeeVee CTO. “There is a lot of confusion and misunderstanding about USB 3.0, USB-C, Thunderbolt, power distribution, etc. USB4 is a good step to bringing this all back under the standard of ‘USB’ instead of implementors having a hodgepodge of things to implement and be aware of separately. When it does start showing up in the wild (likely first on laptops), ZeeVee will have solutions to exploit it.”
HDMI 2.1a: Performance that’s ahead of the curve
HDMI remains a key protocol for many pro AV applications.
“As video purists, of course, we typically baseline performance against HDMI standards,” says David Passey, Harman Professional Solutions director of R&D, video and control. “HDMI has always represented the highest quality in AV delivery, especially for our targeted markets of consumer, computer and professional video.”
The latest version is HDMI 2.1a, which published in February 2022.
“As with previous updates, HDMI 2.1a outlines significant improvements in video resolution and content quality,” Passey says. “Now, for the first time, HDMI 2.1 introduces even higher resolution and colour fidelity with an integrated video compression block called Display Stream Compression (DSC). While the native 8k video (@ 60 Hz up to the perfect 4:4:4 colour space) is outside the 48 Gbps bandwidth of HDMI 2.1, it easily falls within the transport spec when utilising the visually lossless DSC video compression. The result is pristine video all the way to 8K and beyond for high refresh and full colour space presentations, exactly as the content provider intended.”
There’s some debate about how quickly and widely HDMI 2.1a will have an impact in the pro AV world.
“The first HDMI standard came out at the beginning of 2003,” Ooms says. “The earliest products to use this standard in the pro AV market came out in 2008, and only by 2013, there was a 50% adoption rate. That means that 10 years passed between the launch and mass adoption.
“We see the same timeline if we look at HDMI 1.4, which came out in 2009. The first pro AV products using this version appeared in 2014. By 2019, 50% of applicable products included the standard. This means that, on average, there is a five-year gap between the spec release and the phase of early adoption.”
If history is any guide, HDMI 2.1a will make its pro AV debut around 2027. Even so, it’s useful to start exploring its capabilities now, especially for AV firms that cater to bleeding-edge verticals such as oil and gas.
“Given the limited added value of 8K for smaller screens, we think it will mainly be adopted for very specific use cases, such as medical imaging, military applications, the design world, recording studios, and videowalls or large LED screens, especially since the difference between 2.1 and 2.1a is minimal,” Ooms says. “Features with the latter standard include Source-Based Tone Mapping (SBTM), which supports High Dynamic Range (HDR), making blacks blacker, whites whiter, and providing more options with brightness and colour — a larger range.”
But others expect HDMI 2.1a to impact pro AV sooner rather than later.
“As an AVoIP vendor, we are looking at all of these new connectivity standards,” says Steve Metzger, ZeeVee CTO. “However, from a practical point of view, HDMI 2.1a is in our immediate focus since it is starting to show up in the wild.”
“HDMI 2.1 and 2.1a are interesting because they add support for 8K and new HDR,” Metzger says. “The challenge here when putting over an IP network is bandwidth, with 8K requiring over 40 Gb at 50 Hz. Realistically, this requires too much compression to go on a 1 Gb solution, but with limited compression it would be possible on a 10 Gb network. ZeeVee along with SDVoE (Semtech) are currently exploring this option.
“That said, the majority of AV projects still use 1080x1920, with basic 4K take up being slow. As a vendor, we have to make roadmap decisions based on meeting the wider demand, not niche applications.”
Wi-Fi 7: Multiple Gigs and connections
With so many connectivity standards in the marketplace, how do vendors choose which ones to invest their R&D in?
"One of the big things that we look at is our customer base," says Hall's Eagle. "We have a council of key customers who do a big portion of their business with us, and we look at what they have coming on the road."
Wireless can be an attractive option for some applications because it provides installation flexibility and avoids connector and cable confusion. Although 5G is making cellular technology viable for some pro AV applications — such as outdoor digital signage and surveillance camera backhaul — Wi-Fi remains the most common way to cut the cord in classrooms and offices.
The latest version is Wi-Fi 7, which carries on a Wi-Fi tradition: By shipping routers and other products based on the spec’s initial drafts rather than the published version, IT vendors hope to snap up the early adopter market. That strategy could pay off with Wi-Fi 7, judging by an October 2022 Wireless Broadband Alliance (WBA) survey, where 33% of service providers, technology vendors and enterprises said they plan to deploy Wi-Fi 7 by the end of 2023.
“The benefit for a typical Wi-Fi 7 laptop is a potential maximum data rate of almost 5.8 Gbps,” Intel says. “This is 2.4X faster than the 2.4 Gbps possible with Wi-Fi 6/6E and could easily enable high quality 8K video streaming or reduce a massive 15 GB file download to roughly 25 seconds vs. the one minute it would take with the best legacy Wi-Fi technology.”
Like the current version, Wi-Fi 6E, Wi-Fi 7 uses the new 6 GHz band in addition to the traditional 2.4 and 5 GHz Wi-Fi bands. But Wi-Fi 7 goes a step further by using Multi-Link Operation (MLO), which enables a device to have simultaneous connections on two bands. This aggregation can be used to increase throughput or improve reliability through redundancy.
“Channel width will improve, as well,” says Crestron’s Ooms. “With 6 and 6E, we’re at 160 MHz. That increases to 320 MHz with Wi-Fi 7 and takes us from 8x8 MIMO to 16x16 MIMO, which results in even more users per access point.”
As with HMDI 2.1a, Crestron sees Wi-Fi 7 as something that will take a few more years to become a force in pro AV.
“Wi-Fi 6 is now becoming the standard access point, which is very interesting for most applications,” Ooms says. “There are already a number of laptops and access points enabled for 6E, but it’s still in its infancy. Wi-Fi 7 is due in 2024, but it won’t be stable until 2030.
“Pro AV does not use Wi-Fi for video or audio distribution. Wi-Fi 7 can allow us to send DM NVX signals over Wi-Fi, for example, but we are still far away from that option becoming reality.”
Other AV pros see wired technologies remaining the preferred choice for many applications.
“While Wi-Fi may be a good way to connect to the distribution system, it generally is not appropriate as an overall AV distribution method because it does not provide a good means of handling multicast traffic, something AVoIP makes extensive use of in order to keep bandwidth needs under control,” Metzger says. “No matter how much capacity is built into Wi-Fi, it is almost a guarantee that video data needs can swamp it — at least when deployed on a large scale.”
Finally, increased Wi-Fi speeds and usage also will require wired upgrades.
“Wi-Fi 6E has max throughput speeds of 7 Gb/s, which can be done with Cat 6A cabling,” Ron Tellas, Belden technology and applications manager told Inavate in 2021. “Wi-Fi 7 is expected to have up to 30 Gb/s maximum throughput. This would mean that several (up to 4) Cat 6A cables would be needed to a Wi-Fi 7 AP. An alternative would be to run fibre. If power and data is needed to each Wi-Fi 7 AP, then a hybrid fibre cable is also an option.”
Standard in name only?
AV and IT vendors often add their own features and capabilities to a standard as a way to differentiate their products.
“A standard simply describes basic rules that you must comply with, but you’re certainly able to build on that foundation,” Ooms says. “As a manufacturer, you can make a difference by going above and beyond certain standards by adding features even improving quality.”
But value-added features can create challenges for integrators and end users in multi-vendor environments.
“As an AVoIP solution provider, we provide the heart of an AV solution connecting up devices from multiple vendors over a network,” says ZeeVee’s Metzger. “If something isn’t working 100%, then of course the first questions get addressed to us. The vast majority of times, it will be network set up or EDID management. However we have seen issues with USB, HDMI and DisplayPort interfaces not working correctly on third party devices.
“New standards and new methods ALWAYS present challenges because no matter how well intentioned the implementor, there are always slight variations. Since we end up interfacing to many of these new and different methods, we end up being a ‘concentration point’ for incompatibilities and problems. It kind of comes with the business.”