Quick answer: Buy the cable from the panel specification, not the box on the shelf. A 4K60 television with HDR needs 18 Gbit/s and a Premium High Speed cable at AUD 20 to 35. Only a 4K120 console or an 8K panel justifies 48 Gbit/s at AUD 35 to 60. Every Australian free to air and Foxtel feed fits inside 18 Gbit/s, so spend the difference on a second cable for the soundbar. Read the port labels first, because they decide more than the cable does.
A television has three or four HDMI ports that are not equal, and the cable that arrived in the box is often the weakest part of the install. Matching cable, port and source takes ten minutes with the manual open, and it prevents the black screens that get reported as a faulty panel. Do it once at install and the lounge room stays stable for years.
Start with the panel, not the cable
Reading the resolution and refresh rate
The panel specification tells you the native resolution and the highest refresh rate it accepts, and those two numbers set the bandwidth. 4K60 with 8 bit colour fits in 18 Gbit/s. 4K120 at 10 bit needs the full 48 Gbit/s, and so does 8K60. A 4K panel that advertises 120 Hz on one input only will need the good cable on that input.
HDR formats change the bandwidth
HDR10, HLG and Dolby Vision all add metadata, and Dolby Vision at 4K60 pushes close to the 18 Gbit/s ceiling once you allow for 10 bit colour and 4:2:2 sampling. If the TV supports Dolby Vision and the player can output it, use a certified Premium High Speed cable as the minimum and do not rely on a thin one that came free.
Foxtel, Fetch and Freeview boxes
iQ4 and iQ5 output settings
Foxtel boxes output a fixed format chosen in the settings menu, and many are left on 1080i from installation. Setting the box to 4K50 gives a sharper picture on a 4K panel and still fits comfortably inside 18 Gbit/s. If the screen blanks when the box changes format, the cable is marginal rather than the box being faulty.
Antenna and streaming sticks
Freeview through the TV tuner needs no HDMI cable at all, only a working antenna. Streaming sticks sit directly in a port and draw power from the TV, so they need a free 5 V supply more than they need bandwidth. For a second screen in a bedroom, a HDMI splitter 1×2 is cleaner than moving the main box every night.
Soundbars and the audio return path
ARC against eARC
ARC sends compressed surround back down the same cable that feeds the picture, and it needs an ARC labelled port at both ends. eARC carries uncompressed Dolby Atmos and DTS:X and needs more bandwidth, so it depends on a certified cable with the Ethernet pair intact. A cheap lead often passes video and fails on the return channel.
| Device | Max output | Bandwidth needed | Cable category | Price (AUD) |
|---|
| Foxtel iQ4 | 4K50 | 18 Gbit/s | Premium High Speed | 20 to 35 |
| Fetch Mighty | 4K50 | 18 Gbit/s | Premium High Speed | 20 to 35 |
| 4K Blu-ray player | 4K60 | 18 Gbit/s | Premium High Speed | 25 to 45 |
| Gaming console | 4K120 | 48 Gbit/s | Ultra High Speed | 35 to 60 |
| Soundbar with eARC | 4K60 pass | 18 Gbit/s | Premium High Speed | 25 to 50 |
Which port carries the sound
Only one port on most TVs supports ARC, and it is usually labelled ARC or eARC on the case. Plug the soundbar there and keep the console on a different input. If the soundbar has a passthrough port, the order matters: source into the bar, bar into the TV, and the HDMI ARC cable handles the return path while an HDMI eARC cable carries the console feed.
Lengths that suit Australian homes
Wall mounting and cable access
A wall mounted panel in a brick veneer home usually needs 2 m to 3 m from a low cabinet, and 5 m if the cables run down a cavity to a cupboard. Measure the path, not the straight line, and add 300 mm at each end for a service loop. A 5 m passive cable at 4K60 works with 24 AWG conductors and fails with thin ones.
Send the TV model, the box model and the measured path to zongcarrie@zh-zong.com or call +86 13543026126 and we will quote the right cable for each port in AUD, including the soundbar leg. A cable check at the planning stage is free, and it avoids buying a second set after the bracket is on the wall.
Practical scenarios
- Situation: A Glen Waverley brick veneer home with the TV above a fireplace. What to do: Run 5 m of 24 AWG through the cavity with a 300 mm loop.
- Situation: A Parramatta apartment with a soundbar on the cabinet. What to do: Use the ARC port and a certified 2 m cable.
- Situation: A Gold Coast townhouse with a Fetch box, a console and a projector. What to do: Keep the console on the 120 Hz input with 48 Gbit/s.
- Situation: A Cairns holiday rental where guests unplug cables every week. What to do: Label both ends, fit port savers, keep a spare.
FAQ
Is the cable in the TV box good enough?
It usually passes 1080p and often 4K60 over 1 m, which is enough to get started. It is rarely certified and often too short for a wall mount. Replace it when you install the TV properly, and keep the original as a spare for a bedroom set.
Does a more expensive cable improve picture quality?
No. A digital link either carries the data or it does not. Above the certification threshold you are paying for connectors, strain relief and length, not for colour or contrast. Put the saving into a second cable for the soundbar or a longer run to the cupboard.
Why does the sound drop when I use a soundbar?
The return channel needs a cable with all pins connected, including the Ethernet pair, and a cheap lead often omits them. Fit a certified cable, confirm both ends are in ARC ports, and check that the TV audio output is set to the external speaker rather than the internal one.
