Max HDMI cable length?

justjax · 16-07-2013, 13:57

Trying to establish what the max recommend length is for a HDMI cable. Planning to run one from a Media Center PC to the TV, but its probably means running it over about 7-8 meters and therefore I'll probably have to get a 10 meter cable. Lots of 10m cables on Amazon, but I read here that high speed can't be guaranteed over 25ft/7.6 m?

Nigel Goodwin · 16-07-2013, 14:05

The better long cables have amplifiers built-in - this does mean they only work one way round though.

flagpole · 16-07-2013, 14:18

their highs speed can not be guaranteed over that distance. but how much speed do you need?

HDMI 1.4 is spec'd for 48bit/px 1920×1200p60 and 37Mbit audio
most you want is probably 1920x1080p30 24bit/px which is less than a quarter.

my experience with long hdmi cables is that they are prone to interference. from light switches, the ignition on the boiler, that kind of thing. so they need to be reasonable quality for that.

you seem to be able to get a decent one for around a tenner. so it would seem like the best option is to try it.

justjax · 16-07-2013, 15:37

Quote:

Originally Posted by flagpole

their highs speed can not be guaranteed over that distance. but how much speed do you need?

HDMI 1.4 is spec'd for 48bit/px 1920×1200p60 and 37Mbit audio
most you want is probably 1920x1080p30 24bit/px which is less than a quarter.

my experience with long hdmi cables is that they are prone to interference. from light switches, the ignition on the boiler, that kind of thing. so they need to be reasonable quality for that.

you seem to be able to get a decent one for around a tenner. so it would seem like the best option is to try it.

Sorry does 1920x1080p30 24bit/px also apply for Blu Ray players too?

chrisjr · 16-07-2013, 15:40

I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels.

It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference.

This is the 10m version of the lead I used

http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786

justjax · 16-07-2013, 15:55

thanks Chris I'll check it out.

chrisjr · 16-07-2013, 15:57

Quote:

Originally Posted by justjax

Sorry does 1920x1080p30 24bit/px also apply for Blu Ray players too?

Blu-Ray is up to 1920x1080 resolution with various frame rates depending on source. A movie will be 24 frames per second, UK TV is 25 and US TV 30. There are other resolutions and frame rates supported. Whether you will encounter any of them is another matter. As is whether the TV supports them or not.

If you are playing movies then you are most likely to see 1920x1080 24fps which should be well within the abilities of a 10m cable of decent spec.

LCDMAN · 16-07-2013, 17:25

Quote:

Originally Posted by chrisjr

I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels.

It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference.

This is the 10m version of the lead I used

http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786

Chris, used the same 10M cable on a prototype 4K projector - no probs. Love the stuff from CPC, great value.

niall campbell · 16-07-2013, 18:24

http://www.hdmi.org/installers/longcablelengths.aspx

up to 30 metres with just a cable

Nigel Goodwin · 16-07-2013, 19:28

Quote:

Originally Posted by LCDMAN

Love the stuff from CPC, great value.

CPC are great on some stuff (leads in particular), but some other stuff are crazy expensive prices.

LinearCandidate · 19-07-2013, 17:02

Quote:

Originally Posted by chrisjr

I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels.

It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference.

This is the 10m version of the lead I used

http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786

How fiddly was it to install the cabling, and how long approximately did it take you to install the cabling?

grahamlthompson · 19-07-2013, 18:13

I have a 15m cable I normally use at 1080i50 (with a HD camcorder). As an experiment I tried it with a Blu-ray playing a 1080p24 35Mpbs disc (It's the bitrate that matters not the resolution, the bitrate is the amount of data the cable has to move in a given time). No problem at all, it was a relatively cheap cable from e-bay as well.

flagpole · 19-07-2013, 19:01

Quote:

Originally Posted by grahamlthompson

I have a 15m cable I normally use at 1080i50 (with a HD camcorder). As an experiment I tried it with a Blu-ray playing a 1080p24 35Mpbs disc (It's the bitrate that matters not the resolution, the bitrate is the amount of data the cable has to move in a given time). No problem at all, it was a relatively cheap cable from e-bay as well.

The video is sent over HDMI uncompressed. It is decoded by the player, not the display panel. That is the point. The rated speed for HDMI 1.3 is over 10Gbps

It is entirely the resolution, frame rate and bit depth plus the audio that affects the amount of data the cable has to move.

16-07-2013, 13:57	#1
justjax Forum Member Join Date: Oct 2009 Posts: 911	Max HDMI cable length? Trying to establish what the max recommend length is for a HDMI cable. Planning to run one from a Media Center PC to the TV, but its probably means running it over about 7-8 meters and therefore I'll probably have to get a 10 meter cable. Lots of 10m cables on Amazon, but I read here that high speed can't be guaranteed over 25ft/7.6 m?

16-07-2013, 14:05	#2
Nigel Goodwin Forum Member Join Date: Apr 2006 Location: North Derbyshire Posts: 41,789	The better long cables have amplifiers built-in - this does mean they only work one way round though.

16-07-2013, 14:18	#3
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	their highs speed can not be guaranteed over that distance. but how much speed do you need? HDMI 1.4 is spec'd for 48bit/px 1920×1200p60 and 37Mbit audio most you want is probably 1920x1080p30 24bit/px which is less than a quarter. my experience with long hdmi cables is that they are prone to interference. from light switches, the ignition on the boiler, that kind of thing. so they need to be reasonable quality for that. you seem to be able to get a decent one for around a tenner. so it would seem like the best option is to try it.

16-07-2013, 15:37	#4
justjax Forum Member Join Date: Oct 2009 Posts: 911	Quote: Originally Posted by flagpole their highs speed can not be guaranteed over that distance. but how much speed do you need? HDMI 1.4 is spec'd for 48bit/px 1920×1200p60 and 37Mbit audio most you want is probably 1920x1080p30 24bit/px which is less than a quarter. my experience with long hdmi cables is that they are prone to interference. from light switches, the ignition on the boiler, that kind of thing. so they need to be reasonable quality for that. you seem to be able to get a decent one for around a tenner. so it would seem like the best option is to try it. Sorry does 1920x1080p30 24bit/px also apply for Blu Ray players too?

16-07-2013, 15:40	#5
chrisjr Forum Member Join Date: May 2004 Location: Reading Posts: 27,916	I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels. It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference. This is the 10m version of the lead I used http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786

16-07-2013, 15:55	#6
justjax Forum Member Join Date: Oct 2009 Posts: 911	thanks Chris I'll check it out.

16-07-2013, 15:57	#7
chrisjr Forum Member Join Date: May 2004 Location: Reading Posts: 27,916	Quote: Originally Posted by justjax Sorry does 1920x1080p30 24bit/px also apply for Blu Ray players too? Blu-Ray is up to 1920x1080 resolution with various frame rates depending on source. A movie will be 24 frames per second, UK TV is 25 and US TV 30. There are other resolutions and frame rates supported. Whether you will encounter any of them is another matter. As is whether the TV supports them or not. If you are playing movies then you are most likely to see 1920x1080 24fps which should be well within the abilities of a 10m cable of decent spec.

16-07-2013, 17:25	#8
LCDMAN Forum Member Join Date: Dec 2005 Location: Yorkshire, God's County Posts: 5,182	Quote: Originally Posted by chrisjr I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels. It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference. This is the 10m version of the lead I used http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786 Chris, used the same 10M cable on a prototype 4K projector - no probs. Love the stuff from CPC, great value.

16-07-2013, 18:24	#9
niall campbell Forum Member Join Date: May 2006 Location: Aberfeldy Posts: 7,035	http://www.hdmi.org/installers/longcablelengths.aspx up to 30 metres with just a cable

16-07-2013, 19:28	#10
Nigel Goodwin Forum Member Join Date: Apr 2006 Location: North Derbyshire Posts: 41,789	Quote: Originally Posted by LCDMAN Love the stuff from CPC, great value. CPC are great on some stuff (leads in particular), but some other stuff are crazy expensive prices.

19-07-2013, 17:02	#11
LinearCandidate Inactive Member Join Date: Jul 2013 Posts: 27	Quote: Originally Posted by chrisjr I installed a 15m cable in a meeting room at work from a ceiling projector round to where the computer desk is. It works perfectly at any resolution your TV is likely to encounter, ie likely a max 1920x1080 pixels. It also runs pretty close to the mains wiring and the light fittings in the false ceiling without any issues over interference. This is the 10m version of the lead I used http://cpc.farnell.com/pro-signal/ps...dmi/dp/AV14786 How fiddly was it to install the cabling, and how long approximately did it take you to install the cabling?

19-07-2013, 18:13	#12
grahamlthompson Forum Member Join Date: May 2005 Location: Redditch Worcs Posts: 17,293	I have a 15m cable I normally use at 1080i50 (with a HD camcorder). As an experiment I tried it with a Blu-ray playing a 1080p24 35Mpbs disc (It's the bitrate that matters not the resolution, the bitrate is the amount of data the cable has to move in a given time). No problem at all, it was a relatively cheap cable from e-bay as well.

19-07-2013, 19:01	#13
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	Quote: Originally Posted by grahamlthompson I have a 15m cable I normally use at 1080i50 (with a HD camcorder). As an experiment I tried it with a Blu-ray playing a 1080p24 35Mpbs disc (It's the bitrate that matters not the resolution, the bitrate is the amount of data the cable has to move in a given time). No problem at all, it was a relatively cheap cable from e-bay as well. The video is sent over HDMI uncompressed. It is decoded by the player, not the display panel. That is the point. The rated speed for HDMI 1.3 is over 10Gbps It is entirely the resolution, frame rate and bit depth plus the audio that affects the amount of data the cable has to move.

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Max HDMI cable length?