In home theatre installations, long cable runs are a challenge – especially if it’s an HDMI cable that needs to be conduit-fed from an AV receiver to a distant, ceiling-mounted projector, for instance. Inakustik has an elegant solution …
The advent of the High-Definition Media Interface (HDMI) more than a decade ago was a godsend for home entertainment enthusiasts and system installers.
It allows a single cable to carry both multichannel audio and high-resolution video, using a robust connector, and promises seamless digital audio and video data transfer between compatible devices, including TVs and monitors, source components and home cinema processors and receivers.
Since HDMI 1.0 was first introduced in the mid-2000s, the amount of data that HDMI cables are typically required to transfer has increased almost exponentially. In video terms alone, we’ve gone from SD to HD to UHD – and already, 8K is looming.
To put that into perspective, high-definition 720p/1080i video requires three times the data compare to 480i standard-definition video. Move up to 1080p, and the HD data stream is doubled again.
Today’s UHD 4K and even 8K video demand even greater data transfer volumes. Similarly, the digital audio requirement has also become more taxing, both in terms of number of channels, as well as the prevalence of object-based surround sound formats such as Dolby Atmos and DTS:X.
STANDARDS, SPEEDS AND LENGTHS
No wonder that the HDMI specification has undergone a continuous series of upgrades, culminating in the most recent HDMI 2.1 standard. It specifies a rated bandwidth of 48 GBps and the ability to cope with up to 10K resolution at 120 Hz, together with dynamic HDR and enhanced refresh rates, among many other capabilities.
One aspect of HDMI cable capabilities that does not seem to be pertinently addressed by the HDMI specification is cable length. However, it is an accepted fact that the longer the cable, the greater the chance of signal degradation.
By the same token, the greater the data volume and data speed transferred, the shorter the cable needs to be to ensure reliable results. Opinions vary about what the maximum cable length should be for high-res, high-data applications, but 3 metres and below appears be considered reliable for HD-compliant cables.
So, what do you when you need to link two components that are considerably further apart? For instance, connecting a ceiling-mounted digital video projector to an AV processor or receiver can easily entail HDMI cable runs of around 15 metres.
That situation can be made even worse if the cable has to be concealed in conduiting, and has to follow a circuitous route in the interests of a clean, invisible installation. Suddenly, 15 metres can become 25 metres, or more.
Having to conceal the cable also introduces another practical problem: the standard HDMI connector itself is often too bulky to fit through conduits, necessitating either the use of a larger-diameter conduit or an even longer cable run.
One solution to overcome the signal degradation associated with long HDMI cable runs is to use a so-called active cable, which usually entails the use of separately powered in-line boosters and amplifiers, further complicating the installation.
AT FACE VALUE
German cable specialist Inakustik has a more elegant answer to both the signal degradation associated with cable length, and the limitations presented by the standard, bulky HDMI connector in concealed installations.
Its Pro Micro fibre optic-based HDMI 2.0 cable can be used over extended distances, and uses micro-HDMI connectors with adapters to make it easier to feed the cable through narrow conduiting. It also doesn’t require a separate power source.
The Pro Micro is HDMI 2.0 compliant, which means it supports HDCP 2.2, Extended Display ID, and HDR. It is meant to reliably transfer 4K UHD video at 50/60 Hz and 4:4:4 over cable runs of up to 100 metres, at a maximum data rate of 18 GBps. Audio Return Channel functionality is guaranteed, too, but only for runs of up to 50 metres.
The fibre optic cable is directional, and terminated with micro-HDMI plugs that have a compact diameter of only 14,5 mm. The all-metal slimline plugs come with metal adapters that transform the micro-HDMI terminals to standard-sized HDMI versions. These are fitted once the cable has been pushed/pulled through the conduit.
The Pro Micro HDMI cable has been designed to draw its power from the HDMI port of the source component. However the adapter also makes provision for connecting a separate, dedicated power source if required.
I used a 10m length of Inakustik Micro 2.0 HDMI cable between our regular Marantz SR6011 AV receiver and the Optoma HD80 DLP projector installed in a ceiling-mount position in the AVSA listening room. Providing the source signal was an Oppo BDP-95EU universal deck.
The distance between receive rand projector is about 5m, but given the cable path, using conduiting into the ceiling, and then running the cable along the wall before tacking across to the projector, required almost all of the 10m cable reviewed here.
Installation was a simple plug-and-play affair. The cable is provided on a handy reel that keeps it tangle-free during the installation process. Inakustik provides a clever little plastic housing that slips over the actual micro-connector, and protects the termination during the installation procedure.
The actual cable is relatively thin and round, with a smooth, black PVC sheath that was easily pulled through some existing (and cable-crowded) conduiting in the AVSA listening room. As mentioned, the cable is directional, and the connectors are clearly marked ‘source’ and ‘display’.
Tactile quality is impressive. The micro HDMI plugs on either side are made of solid metal, with anodised aluminium housings, and gold-plated connectors. The full-size HDMI adapter slides onto the micro-HDMI connector via an integrated groove that ensures perfect alignment and a snug, positive fit.
If external power is required, the adapter includes a power socket directly below the micro HDMI, which accepts the dedicated jack-to-USB cable provided. The cable can then be coupled to any generic USB charger.
I ran the Inakustik in tandem with the existing cable, made possible by the fact that the Optoma has two HDMI inputs, and that the Marantz offers two HDMI outputs (although the second output doesn’t offer ARC, which is relevant in this set-up anyway). This allowed back-to-back comparisons.
WORKS LIKE …
Once connected, the Optoma instantly recognised the incoming signal and locked onto it – a process that can take 10 to 15 sec with our existing, older generation HDMI cable. That alone was a good indication of signal strength and integrity.
I then used the Inakustik cable to watch a number of favourite Blu-ray titles – unfortunately, we don’t have 4K capability in our evaluation room. I’d be lying if I told you I saw a massive difference in image in quality, compared to the system’s performance with our own cable.
That said, I subjectively found the colour reproduction achieved with the Inakustik slightly more vivid, with subtly improved contrast levels and better low-light detail. This could be proof that the existing cable suffers from some signal degradation to its length, while the Inakustik showed no sign of any untoward artefacts.
For instance, I felt that the many gloomy scenes in Star Wars: The Last Jed’ were delivered with greater clarity and detail, and that fast-moving action sequences in Inception appeared to be rendered with crisper realism.
The improvements were subtle rather than groundbreaking, but still repeatable and noticeable across all the material I compared. In my opinion, that made them significant enough to warrant the investment in the optical cable upgrade – and a must-have scenario where cable runs are even greater than the 10m length tested here.
I’m the first to admit that it makes sense to assume that all HDMI cables compliant with a particular set of measurable standards should deliver performances that are technically and qualitative identical. That’s why the standards are set in the first place.
However, real-world applications can still show up differences – sometimes due to simple variances such as termination, connector fit, shielding etc. The Inakustik Pro Micro’s fibre optic construction should make it more resistant to the potential interference that could plague conventional cables.
Just what impact the Inakustik cable will have when compared to ‘normal’ HDMI cables of the same 2.0 standard will depend on many factors, not least of which will be the quality of the installation, the distances involved, and the capability of the system components.
THE BOTTOM LINE
The InAkustik Pro Micro operated flawlessly in our system. It was easy to install, and both the design and the quality of the connectors was impressive, suggesting both performance and longevity.
The video performance improvements may have been subjective and subtle, but the overall value proposition is compelling. That’s especially true where longer cable runs and inaccessible installations demand a HDMI solution that is bulletproof and technically uncompromised, while consistently delivering the AV goods.
And that’s exactly what the InAkustik Pro Micro does.
Type: Active fibre optic HDMI cable
HDMI standard: V2.0
Review sample length: 10m
Maximum recommended length: 100m
Bandwidth/data rate: 18 GBps
Video performance: 4K @ 50/60 Hz, 4:4:4
Supported features: HDCP 2.0, EDID, HDR, ARC (up to 50m)
Accessories included: Micro-HDMI to HDMI adapter, USB DC power cable
Micro-HDMI connector dimensions (LxWxH): 35,5 x 13,7 x 9,8 mm
Micro-HDMI connector diameter: 14,5 mm
Optoma HD80 DLP projector
Oppo BDP-95EU universal player
Marantz SR-6011 AV receiver
Atlantic Technology 7.1 surround sound speaker system
Eyes Wide Shut (Blu-ray)
Star Wars: The Last Jedi (Blu-ray)