HDMI 2.1 cables really make a difference

HDMI 2.1
100% human

In case you do not know most 2019, and 2020 TVs only have the HDMI 2.0 (4K). Moving forward, most TVs should have HDMI 2.1 (8K). So, what does that mean to you?

We wrote a guide on HDMI here that should be mandatory reading if you are buying a 4K or 8K TV. We set out to test HDMI 2.0 and 2.1 cables and see if it makes a tangible difference over HDMI 1.4 cables.

Just to be clear – HDMI is an input/output port/cable for connecting external content sources to a TV like a 1080p DVD, 4K Blu-ray, NVIDIA Shield 4K TV, Apple TV, Roku/Telstra, Dolby Atmos soundbar, Games console, PC, set-top box and more.

We are referring to the bandwidth needed to transmit 4K, HDR/HDR10/Dolby Vision and Atmos to the TV set. If you are connecting nothing – just free-to-air and or using the inbuilt apps, then stop reading now.

The bottom line is that 99.9% of cables you can buy are in fact version 1.4 ‘high-speed’. They barely work for 4K@30fps transmission – you would be surprised just how much you are missing.

Why? Think of an HDMI cable as a funnel.

  • Standard 1.4: 5Gbps up to 720p or 1080i resolution at a 30Hz refresh rate
  • High-Speed 1.4: 10Gbps up to 4K resolution (including 1080p) at 30Hz
  • Premium-High-Speed 2.0: 18Gbps up to 4K resolution with high dynamic range (HDR) at up to 60Hz
  • Ultra-High-Speed 2.1: 48Gbps (and up to 120Gbps for 10K resolution with HDR at a 120Hz refresh rate (4K video can refresh at up to 240Hz)

So, because 1.4 does not support Dolby Vision or Dolby Atmos – you may as well not have bought a 4K TV as all you are getting is standard definition upscaled to 4K!

While writing the HDMI tutorial we spoke to Chris Lau of the owner of Laser that makes a vast range of cables and accessories sold in most electronics and chain stores. He said:

“Most people don’t know that there are different categories of HDMI cables. They never know that the lower cost ones don’t support deep colour, HDR or many of HDMI’s latest feature like Dolby Atmos. We are seeing a huge demand for HDMI 2.1 cables so for now buy Category 4 Ultra High Speed if you have a 4K Dolby Vision/Atmos TV and Blu-ray player that supports Dolby Vision and Atmos.”

Chris offered, and we gratefully accepted to send some Premium high-speed 2.0 and Ultra-High-speed 2.1 cables to test.

If you have a late model 4/8K HDR/10/10+/Dolby Vision/Atmos and are connecting any HDMI devices, please read on.

Spoiler alert – good cables cost good money but make a huge difference

Laser Premium High-speed 2.0b cables with Ethernet 2/3/5metres $79.95/99.95/129.95

These ooze quality with a braided nylon protective jacket gold-plated connectors. At 18Gbps they will support 4K@30fps Dolby Vision and Atmos pass through.

HDMI 2.0

 In our HDMI guide, we said that Premium-High-Speed was all you need to get the most out of a decent 4K TV – and it is. We connected

That setup previously had HDMI 1.4 High-speed cables. All we were getting was 4K@30fps SDR (not HDR let alone Dolby Vision) and Dolby Atmos converted to PCM audio.

Now we were not stupid – the earlier Sony TV 55-X9300 (now replaced by the Sony A9G OLED) had one HDMI 2.0 ARC port, HDR (not Dolby Vision) and passed through 5.1 Dolby Digital (Not Atmos) to a soundbar. It only needed HDMI 1.4 High-speed cables. The new TV needed more.

Laser Ultra-high-speed 2.1

These are for 8K HDMI 2.1 TVs requiring the 48Gbps bandwidth although they are backwards compatible.

The difference was at palpable. An Immediate upgrade from Dolby Digital over PCM to true 7.1.4 Dolby Atmos and from HDR to the amazing Dolby Vision – it was like it was a whole new system.

We are still shaking our head at the visible difference. Go out and splurge if you like the best out of your TV experience.

HDMI 2.1

eARC seemed to connect faster, it also found the devices by name (instead of HDMI 1/2/3/4 etc.) and even changed to the active device connected to the Samsung soundbar.

I am not a gamer, but I think that if I had an Xbox One X or PS4 Pro, I would splash out on the Laser 8K 48Gbps cable.

This new standard supports (if your TV and devices do)

  • 8K@60fps or 4K@120fps
  • Up to 10K (compressed)
  • Dynamic HDR and High Frame Rate (HFR)
  • eARC and ARC
  • AMD Freesync 2 HDR
  • Dolby Atmos 7.1.4 (up to 32 channels)
  • 21:9 cinema mode
  • Dual video stream
  • VRR Game mode
  • Auto Low Latency Mode (ALLM)
HDMI 2.1

Price: Not available yet. FYI a Belkin 1/2metre is $99.95/129.95