HDMI cable: what length is allowed and how to extend?

Sometimes it depends on the length. Especially with HDMI cables. In the following, we will introduce you to the various options for HDMI extension.
HDMI cable length: What are the limits?
According to the HDMI Licensing Organization, lengths of up to 10 meters can be easily achieved with a high-quality 10m HDMI cable without having to amplify the signal. For anything beyond that, the signal in the HDMI cable theoretically needs to be amplified with a separate solution. Special HDMI repeaters are suitable for this purpose. However, whether or not signal amplification is necessary in practice depends largely on the components used - especially the HDMI receiver chip installed in your TV. The better it is and the more functions it supports (e.g. cable equalization), the more likely it is that the receiver chip can also process weak signals. In other words: What works with your current TV set does not necessarily work just as well with another device.

Is there a loss of quality from 10 meters?
If the length of an HDMI cable is more than the 10 meters recommended by the HDMI organization, problems can occur. Don't worry: "creeping" or subliminal quality losses, as with analog signals in the past, are not possible with HDMI. Thanks to the digital TMDS Technolgie, which is the basis of all HDMI cables, picture and sound are either transmitted crystal clear or there are obvious errors such as a total loss.

HDMI length up to 10m - The quick solution with extension cable
If you already have a short HDMI cable (usually under 5m) in use and just want to extend it by another short piece, an HDMI extension cable is recommended. In this way, several HDMI cables can be plugged together and thus quickly reach the desired length. With an extension cable you can "plug together" HDMI cables up to a total length of max. 10m. Anything longer can work, but depends on the individual case and the components used.

Alternative tip: A single 10m HDMI cable about as much and is less susceptible to interference than two HDMI cables plugged together.

HDMI extension up to 40m: A HDMI repeater is needed
If you want to bridge more than 10 meters, the signal in the cable must be amplified. For this purpose, the use of an HDMI repeater for HDMI extension is recommended.

A repeater connects two HDMI cables together and amplifies the signal so that it arrives at the signal receiver without loss. The HDMI cables connected to the repeater should not be longer than 10m each. The HDMI Repeater usually does not need a separate power source. In our experience, chains of up to 40 meters can be achieved by combining several HDMI repeaters and HDMI cables. Make sure that the input and output ports of the repeater are wired correctly - otherwise there is no gain.

If you need more than 40m cable length in extreme cases, even a HDMI repeater comes to its limits. For this you need a so-called Cat. 5/6 Extender. For this purpose, the technology of network cables (Cat. 5/6) is used to transport the HDMI signal. In this way, lengths of up to 300 meters can be achieved.

High length - high risk? Reduction of risk sources
With an HDMI cable length of maximum two to ten meters, any well processed high-speed cable is suitable.

However, if you want to bridge a greater range via HDMI, you should pay attention to high-quality components that provide as little signal resistance as possible. This is especially true for the HDMI cables used between repeaters and HDMI extension cables.

In any case, you should use HDMI cables that comply with the HDMI Highspeed standard. Since cable version 1.3, the HDMI organization has defined precise cable characteristics in terms of attenuation, signal propagation delay differences, crosstalk, etc.. With a Highspeed cable you are on the safe side.

With two HDMI highspeed cables and a good repeater, cable connections of up to 20 meters can be achieved easily and cost-effectively. That should be enough for most users. If you need even more length, you can combine HDMI repeater and cable. If in doubt, try it out. If your picture and sound signal arrive at the signal receiver, everything is fine. There is no subliminal loss of quality with an HDMI extension.

If 10 meters is long enough for you, we recommend a one-piece 10m HDMI cable - this solution is inexpensive, low-interference and visually inconspicuous. In general, the longer the cable connection, the higher the risk of signal loss and the more recommendable a high-quality HDMI cable with low signal resistance.

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