Optical is used for sound and is similar to digital coax. It does not have the capability to carry as much data as an HDMI.
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Optical vs. HDMI input
What's the difference between the 2. From good to best is coaxial; Red, White, Yellow; S-Video; Green, Blue, Red; HDMI. Is the optical like a HDMI? What is the optical input function? Any help would be appreciated.
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You are mixing video and audio there. HDMI is a digital connection that carries both audio and video. It is a large pipe that can carry a lot of data. Optical and coaxial are also digital, but just do audio. They both use an older digital format called S/PDIF. Optical and coax are pretty much the same, except for the physical cables that are used. SPDIF cannot carry nearly as much data. The larger HDMI pipe allows it to carry multichannel PCM and the new codecs such as TrueHD. SPDIF can only carry two channel PCM and older 5.1 codecs such as Dolby Digital and DTS. The red and white RCA cables are at the bottom of the list. They can carry one analog channel a piece and they are normally used in a pair for stereo.
Composite (yellow), s-video, and component (green, red, blue) are all different kinds of analog video cables. Component is the only analog connection that can handle HD signals. DVI was the first digital video cable. HDMI, which carries both video and audio, has replaced DVI in home audio/video applications.
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Originally Posted by blueyzfr6 /forum/post/12924827
What's the difference between the 2. From good to best is coaxial; Red, White, Yellow; S-Video; Green, Blue, Red; HDMI. Is the optical like a HDMI? What is the optical input function? Any help would be appreciated.
You are mixing video and audio there. HDMI is a digital connection that carries both audio and video. It is a large pipe that can carry a lot of data. Optical and coaxial are also digital, but just do audio. They both use an older digital format called S/PDIF. Optical and coax are pretty much the same, except for the physical cables that are used. SPDIF cannot carry nearly as much data. The larger HDMI pipe allows it to carry multichannel PCM and the new codecs such as TrueHD. SPDIF can only carry two channel PCM and older 5.1 codecs such as Dolby Digital and DTS. The red and white RCA cables are at the bottom of the list. They can carry one analog channel a piece and they are normally used in a pair for stereo.
Composite (yellow), s-video, and component (green, red, blue) are all different kinds of analog video cables. Component is the only analog connection that can handle HD signals. DVI was the first digital video cable. HDMI, which carries both video and audio, has replaced DVI in home audio/video applications.
Thanks BI, the wealth of knowledge on this site is truly amazin.
Correction, optical is identical to digital coax. Both are SPDIF.
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Optical is used for sound and is similar to digital coax.
Correction, optical is identical to digital coax. Both are SPDIF.
Hi. New to the forum and just trying to educate myself on the technology as am about to update my system!
Re the older 5.1 codecs. If you are a playing a regular DVD (not blu ray disc) which has the DTS codec (Gladiator for example) on a blu ray player and receiver which are linked through HDMI, are you saying that the DTS can't be enabled? If not, would you still be able to acheive the same audio effect that DTS offered?
Thanks in advance to anyone who could help
Re the older 5.1 codecs. If you are a playing a regular DVD (not blu ray disc) which has the DTS codec (Gladiator for example) on a blu ray player and receiver which are linked through HDMI, are you saying that the DTS can't be enabled? If not, would you still be able to acheive the same audio effect that DTS offered?
Thanks in advance to anyone who could help
Are you asking if you can select the DTS track? I do it routinely with my Blu-ray player.
...for consumers. SDI has been around for a long time.
Component video doesn't carry Red green or blue signals either.
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DVI was the first digital video cable.
...for consumers. SDI has been around for a long time.
Component video doesn't carry Red green or blue signals either.
Hi. I know this is slightly off topic but rather than start a new thread I just wanted to ask about configuration using HDMI.
My TV signal comes direct from a digital antenna which I currently plug directly into a DVD recorder which I connect via HDMI to the TV. I am looking to add an AV receiver, a 5 speaker set up and a blu ray player.
I assume that I use the HDMI output from the AV receiver to connect to the TV. This being the case would the Blu Ray player only need to be connected to the Receiver via HDMI and would this give me 5.1 sound?
Also, on AV receivers there is an "antenna in" option. Am I right in thinking that this would not be used as the antenna goes first into the DVD recorder which is being connected directly to the TV?
Many thanks. Great forum
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My TV signal comes direct from a digital antenna which I currently plug directly into a DVD recorder which I connect via HDMI to the TV. I am looking to add an AV receiver, a 5 speaker set up and a blu ray player.
I assume that I use the HDMI output from the AV receiver to connect to the TV. This being the case would the Blu Ray player only need to be connected to the Receiver via HDMI and would this give me 5.1 sound?
Also, on AV receivers there is an "antenna in" option. Am I right in thinking that this would not be used as the antenna goes first into the DVD recorder which is being connected directly to the TV?
Many thanks. Great forum
Not sure what you mean here. There's no problem sending DTS over HDMI. DTS can be sent over S/PDIF and over HDMI. HDMI adds support for the newer lossless formats. But, it still does regular DTS.
Yes. You'd plug the outputs of both your DVD recorder and your BD player into the AVR, which extracts and processes the audio for surround sound and acts as a video switcher to feed your TV.
Receivers don't have DTV tuners. You need to do the tuning elsewhere (your DVD recorder, a cable box, etc) and feed to resulting video and audio to your AVR.
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Originally Posted by Loz2009 /forum/post/16897570
Yes. I was confused because how I'm reading this is that the HDMI signal is different to the S/PDIF signal which was what the DTS codecs were designed for.
Not sure what you mean here. There's no problem sending DTS over HDMI. DTS can be sent over S/PDIF and over HDMI. HDMI adds support for the newer lossless formats. But, it still does regular DTS.
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Originally Posted by Loz2009 /forum/post/16897907
My TV signal comes direct from a digital antenna which I currently plug directly into a DVD recorder which I connect via HDMI to the TV. I am looking to add an AV receiver, a 5 speaker set up and a blu ray player.
I assume that I use the HDMI output from the AV receiver to connect to the TV. This being the case would the Blu Ray player only need to be connected to the Receiver via HDMI and would this give me 5.1 sound?
Yes. You'd plug the outputs of both your DVD recorder and your BD player into the AVR, which extracts and processes the audio for surround sound and acts as a video switcher to feed your TV.
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Also, on AV receivers there is an "antenna in" option. Am I right in thinking that this would not be used as the antenna goes first into the DVD recorder which is being connected directly to the TV?
Receivers don't have DTV tuners. You need to do the tuning elsewhere (your DVD recorder, a cable box, etc) and feed to resulting video and audio to your AVR.
OK that makes sense now. Thanks a lot for your help
Well, there is at least one major and important potential difference. An optical link automatically maintains electrical isolation between gear where coax implementations don't unless you purposefully add the parts to make it happen.
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Originally Posted by ChrisWiggles /forum/post/12939620
Correction, optical is identical to digital coax. Both are SPDIF.
Well, there is at least one major and important potential difference. An optical link automatically maintains electrical isolation between gear where coax implementations don't unless you purposefully add the parts to make it happen.
If the coax interface is built according to the standard, there will be a pulse transformer at each end, providing galvonic isolation.
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An optical link automatically maintains electrical isolation between gear where coax implementations don't unless you purposefully add the parts to make it happen.
If the coax interface is built according to the standard, there will be a pulse transformer at each end, providing galvonic isolation.
The facts are: a great quantity of consumer gear will not isolate through the coax port.
BTW pulse transformers are often used merely for the impedance matching they can offer. I'm not familiar with the spdif specs enough to comment with authority why the spec calls for them, as you say it does, but do know that impedance matching can be achieved using pulse transformers without leverging the fact that they could also be used to create electrical isolation. IOW just requiring the use of a transformer does not gaurantee the circuit ends up isolated.
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Originally Posted by duvetyne /forum/post/16901904
If the coax interface is built according to the standard, there will be a pulse transformer at each end, providing galvonic isolation.
The facts are: a great quantity of consumer gear will not isolate through the coax port.
BTW pulse transformers are often used merely for the impedance matching they can offer. I'm not familiar with the spdif specs enough to comment with authority why the spec calls for them, as you say it does, but do know that impedance matching can be achieved using pulse transformers without leverging the fact that they could also be used to create electrical isolation. IOW just requiring the use of a transformer does not gaurantee the circuit ends up isolated.
The fact is it's not built to spec.
OK...maybe you should read the spec.
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The facts are: a great quantity of consumer gear will not isolate through the coax port.
The fact is it's not built to spec.
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but do know that impedance matching can be achieved using pulse transformers without leverging the fact that they could also be used to create electrical isolation.
OK...maybe you should read the spec.
Doesn't mean it isn't extremely common. What's your point?
Uh, and I would want to for what reason? Maybe you should complain to someone who could actually make a difference if it is such a big deal to you.
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Originally Posted by duvetyne /forum/post/16903981
The fact is it's not built to spec.
Doesn't mean it isn't extremely common. What's your point?
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OK...maybe you should read the spec.
Uh, and I would want to for what reason? Maybe you should complain to someone who could actually make a difference if it is such a big deal to you.
Well I have my doubts about the rquirement for isolation in the spec based on the amount of gear which isn't. Like I said though I don't know for sure and so wouldn't make a claim one way or the other.
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If there is a spec and no one adheres to the spec, what good is the spec?
Well I have my doubts about the rquirement for isolation in the spec based on the amount of gear which isn't. Like I said though I don't know for sure and so wouldn't make a claim one way or the other.
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