DTG Testing underlines the importance of “getting the tech match” right between sound bars and slim-line TVs

The modern trend for standalone speakers – alongside the TV display – is causing some screens to “downgrade” their pictures to an inferior quality image, according to DTG Testing.

The organisation was founded in 2000 and is the UK digital television industry’s interoperability testing house. The group provides product testing services for manufacturers, demonstrating conformance to the UK Freeview HD, Freeview Play, Freeview New Zealand, Freesat, HbbTV, at800 and Ghana Digital Thumb logos. The Test Centre’s receiver “Zoo” houses the UK’s largest collection of representative samples of Freeview and Freesat receivers. The collection has been used to support the UK digital switchover by gathering data about the capability of receivers deployed in the UK and is currently used by developers of interactive applications, testers for pretransmission testing and HDMI interopearbility.

For pay TV operators, the problem is that when a TV doesn’t work, they are the first point of call for the irate customer, even though the issue can be caused by any one of a number of peripherals. At one end of the sound bar market, there are high-end manufacturers, then there are some mainstream TV brands who are using their sound bars as a means to upsell the customer, having inadvertently reduced their built-in speaker quality as the displays became ever- thinner.

Ian Medland, Associate Director, DTG Testing, says: “If a sound bar from one manufacturer doesn’t work with a panel from another, who do you blame? It’s a lot more dif cult to have that conversation than it is with, say, a Sky sound bar because you’re paying them money every month and it’s them you want to shout at.”

But just because it’s a sound bar that’s connected doesn’t mean the problems are always going to be around audio. The DTG Zoo reports issues around copy protection, particularly those around Ultra UD, which has much more restrictive rules as to what can and can’t be displayed, leading to a failure mode that restricts the video to regular HD. Worse, the displays can offer a black or flickering screen as the device tries to renegotiate copy protection.

Every additional device in the chain can interfere with other parts of the system. Medland adds: “If you go for low-cost devices they’ll be restricted to lower versions of HDMI, so you’ll suddenly nd out that although your panel is Ultra High-Def compatible, your sound bar isn’t, so if you route it through your sound bar and through to the TV, you might suddenly find that the sound-bar is preventing the full capability of the TV panel being exposed to the set-top box, so that it thinks it only needs to send an HD signal.”

In addition to the multiplicity of devices, manufacturers are also dealing with a complex web of audio formats with no clear market favourite yet to emerge.

Medland says it’s still too early to say who will gain the lead, with broadcasters remaining somewhat conservative, however, the pace is being set by Net ix and Apple TV who are looking at fully immersive formats such as Dolby Atmos.


He says: “TV manufacturers say that the people driving the device specifications are no longer the broadcasters, and certainly not the free-to-air channels. Instead, the driving force is what’s necessary to get Amazon and Net ix on board.”

Despite the success of Freeview Play and YouView in bringing catch-up TV services to millions of terrestrial homes, Medland believes UK platforms are behind their European counterparts when it comes to audio.

With the number of sound bars – and accompanying technical issues – multiplying, manufacturers have been bringing their product to the DTG’s London-based facility, so they can test them against the majority of UHD and Full HD panels currently in the market.

Ranjeet Kaur, Head of Delivery, DTG Testing, says: “This is heaven for the manufacturers because they’ve got all the devices in the one place and they can test all these compatibility and interoperability issues of the Soundbars and the HDMI sources”.