With the debut of Thunderbolt, pro AV is getting another interface, like it or not. Tim Kridel examines how the interface ecosystem is evolving.
Unveiled in September 2009 as a project code-named “Light Peak,” Intel’s Thunderbolt interface is working its way into commercial products. The first is Apple’s February 2011 refresh of its MacBook Pro laptops, a product type that highlights one of the reasons why Thunderbolt is an interface that AV pros should keep an eye on.
The first-generation version of Thunderbolt supports up to 10 Gbps and is backward compatible with existing DisplayPort displays and adapters. One question is whether Thunderbolt will build enough of an installed base in the PC world that, as with DisplayPort, pro AV vendors and integrators have no choice but to accommodate it — sort of.
“DisplayPort definitely is becoming more popular,” says Michael Lane, integration manager for AVI-SPL’s Atlanta office. “It’s on lots and lots of laptops, and it’s starting to show up on displays. There are a number of projectors with DisplayPort.
“However, from an integration perspective, there’s really nothing that will transport or interface with DisplayPort itself. On our side, it’s typically using the features that let it output an HDMI signal. In just about every case where we’re running into DisplayPort, we’re simply adapting it to HDMI.”
A jolt to the industry?
Thunderbolt was designed to use fibre optic cables, but the initial commercial version also supports copper – possibly explaining the name change from Light Peak. (Intel declined an interview request.) The interface also supports bi-directionality and daisy chains of up to seven devices. Will the latter feature help Thunderbolt displace USB in the marketplace?
“Nothing is going to replace USB,” says Brian O'Rourke, In-Stat principal analyst. “It’s too well-established and prominent. It’s most likely to replace DisplayPort because of its high bandwidth and its ability to transport video streams.”
So far, AV pros are cautiously optimistic about Thunderbolt, partly because they have yet to work with it.
“I think it’s going to fall into kind of the same method of DisplayPort where it’s typically going to be adapted to HDMI,” Lane says. “One thing that needs to be watched out for is that it appears that when you do that, it has to be the last thing in the chain.”
Many of the integrators and vendors interviewed for this story singled out speed as one of Thunderbolt’s big draws.
“Thunderbolt’s transmission speed is pretty impressive,” says Michael Bucklin, an AV associate at Shen Milsom & Wilke, a U.S.-based consultant. “It’s too early to tell how this will be implemented by manufacturers. I assume if it becomes widely used, transport manufacturers will come out with I/O boxes to pass it over fibre or category cabling.”
Like other interfaces, Thunderbolt’s presence in pro AV will depend at least partly on whether PC vendors embrace it. As one of the world’s largest chipmakers, Intel obviously plays an influential role, as does Apple.
“The creative industries tend to favour Apple products, so Thunderbolt will likely be propelled along by the huge fan base that Apple maintains,” says Hagai Gefen, president and CEO of Gefen.
Good-bye, DVI?
Pro AV vendors consider several factors when deciding which interfaces to build into their product, including license fees and royalties, maximum cable distance, support for applications such as tiled displays and the installed base of other products that have the interface.
The latter typically includes PCs and consumer products such as TVs, for a couple of reasons. First, many pro AV products – such as projectors – must be able to connect to laptops, such as in conference rooms, so vendors have to match what PC manufacturers are building into their products.
Second, some clients try to save money by using consumer products, such as TV sets for digital signage applications. That can cause integration problems, such as difficulty monitoring and managing TV sets when they don’t have an RS232 port to handle control data.
“The consumer market is definitely a major contributor because the lines are blurring all the time, especially with mobility, streaming and IPTV coming into the mix,” Gefen says. “Gefen’s position has always been to support the widest array of interfaces that we feel will be valid for some time in the future. The lifecycles have definitely shortened a bit. There are already some rumblings about the end of DVI, which has only been around for about a decade.”
Other vendors agree.
“I think you’re seeing the slow disappearance of DVI on consumer computer productivity products,” says Chris Bundy, director of marketing at Atlona Technologies, whose products include cables and switchers.
But slow is a relative term. Even if every consumer manufacturer yanked DVI from its product line-up tomorrow, pro AV vendors still would have to support it for years to come because there’s an installed base of DVI devices.
“We’ll still see DVI for the next five or so years,” Bundy says.
Client budgets are another reason why some interfaces stick around longer than expected.
“Existing equipment, or available equipment, is often chosen to save initial costs,” says Ed Caceres, Magenta Research director of engineering. “While steaming full ahead on new technologies is always desired, the sheer simplicity and robustness of VGA or even component video cannot be ignored.
Content sources are yet another factor.
“For all unprotected content generated by PC-based platforms, the path of least resistance to connecting that source PC is often chosen,” Caceres says. “That path still, even in 2011, can include VGA and DVI outputs. The news of their untimely demise has been grossly overstated.”
Samsung is another vendor that’s bullish on DVI.
“We believe that DVI is the best way forward,” says Sotos Mandalos, Samsung UK technical product manager. “DVI [has] the thumb screws that can be securely fastened onto the large-format displays. Also, you can have component signal going through DVI, making it very easy to daisy chain large-format displays to form video walls, and without having the need to invest in expensive signal-distribution amps.”
HDMI: Grin and bear it
HDMI, meanwhile, shows no signs of beginning a phase-out any time soon. One reason is because although it has several limitations for pro AV applications – including content-protection headaches, no built-in support for locking connectors and a limited range – it’s still widely used on consumer devices that frequently show up in the pro world.
Another reason is that some of those limitations are being addressed. For example, some vendors now offer add-ons that lock HDMI connections, and the organisation that licenses HDMI says it’s “actively evaluating” locking connector solutions. Just as important, there’s a growing number of pro products that use HDBaseT as a way for integrators to work around HDMI’s shortcomings.
“Now you’re able, at a little lower cost point, to provide that same perfect digital image up to 300 feet,” says Paul Hand, product manager for AMX’s AutoPatch group.
Atlona’s Bundy believes that in both consumer and pro, HDBaseT will become a dominant interface over the next two years. For example, he expects display vendors to start supporting HDBaseT via a Cat5 port on their gear.
“Here’s why: I don’t have to waste time with baluns any more,” Bundy says.
Any HDBaseT source should be able to output a signal up to 330 feet over Cat5. I’m saving money on cable connections [because] I don’t have to deal with HDMI adapters. In the digital signage world, I think HDBaseT is going to take over.”
Other AV pros say that HDBaseT’s distance and cable flexibility are two big draws.
“HDBaseT quickly is becoming the best method for high-resolution, digital media over category cabling,” says Shen Milsom & Wilke’s Bucklin. “This is the distance we have been looking for: We can follow best practices established by the telecommunications industry – 300 feet or less = category, 300 feet or greater = fibre – which will make structured cabling systems easier to implement.”
Taking a stand
But HDBaseT also is an example of how standards sometimes still have multi-vendor interoperability problems, as manufacturers look for ways to differentiate their standards-based products.
“Part of the problem is that every manufacturer is adding their little piece on top of HDBaseT, so there’s no real standard there,” says AVI-SPL’s Lane. “From everything I’ve seen so far, you really can’t [mix vendors].”
That’s what Bucklin is seeing, too.
“As I understand it there are some communications channels as part of the standard that some manufacturers are using, but others are layering their own stuff on top,” Bucklin says. “What I worry about with this is fragmentation of HDBaseT technologies potentially reducing or eliminating interoperability.”
Some in pro AV argue that the industry needs to tackle interoperability on its own by taking the existing interfaces and developing recommended practices and other guidelines.
“This is a major industry, and not to have any interface and interoperability standards and recommended practices is irresponsible,” says John Lopinto, Communications Specialties president and CEO. “Computer, broadcast, the industries that the AV industry takes its cue from: They all have defined interoperability standards, which allows the system integrator or end user to buy best of breed, to lower their cost, to place manufacturers in competition with one another.
“Look at the broadcast industry: You can have a Sony camera interface with a Grass Valley switcher going through an Ensemble Designs processor being displayed on a JVC monitor, and it all works.”
ATSC and SMPTE are two examples of how an industry’s manufacturers and even end users can work together.
“InfoComm should be taking the lead,” Lopinto says. “They could set up committees where competitors can get together legally.”
Interoperability efforts could include addressing problems with HDCP and other content-protection schemes, which make interfaces such as HDMI a headache to work with.
“You plug a Blu-ray player into some manufacturer’s pro AV equipment, and God knows what the results will be,” Lopinto says. “Sometimes it works. Sometimes it doesn’t. It’s a mess, which is why you’re starting to see companies like Kramer advocate for using HD SDI, which is an unencrypted signal distribution system that can support 1080p and beyond.”
If there’s an upside to interface-related hassles, it’s that they’re another opportunity for integrators to work that kind of magic that clients are willing to pay for.
“There’s still a lot of value from an integration standpoint to make sure that everything is going to play nicely together,” says AMX’s Hand. “A really good reason why component video is still alive today is because HDMI with HDCP is very difficult in many cases to successfully deploy.”