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What's the Matter with HDMI?
mrnomas writes with a link to the Audioholics site, which wonders why the HDMI standard is such a mess? The article's author suggests that the format was designed for the benefit of the content-producers and not the consumer. The result is a signal that's hard to route and switch, as well and unnecessarily complicated cable assemblies. They reach back to the DVI standard to see what might be done to make HDMI a little more consumer-friendly, with numerous technical elements woven through the discussion. "DVI lacked a couple of things which the consumer audio/video industry wanted. It was implemented on a variety of HD displays and source devices, but it was confusing for the consumer because of the many variants on the standard and different connector configurations, and it didn't carry audio signals. A consortium to develop and promote a new interface, HDMI, was formed; the idea was to come up with a standard which could be implemented more uniformly, was less confusing, and offered the option of routing audio signals along with video."
The HDCP copy protection crap is what causes HDMI devices to have trouble communicating with each other, especially if there is anything between the source and display devices, like an A/V receiver or HDMI switch box.
They are too stupid to realize that pirates aren't going to copy shows and movies by capturing uncompressed frames coming through the cables; they're going to make copies of the discs. But they insist on making the honest customers suffer through the slow cryptographic handshake that occurs any time you switch on an HDMI device or even switch sources on a TV.
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There is inferior bacteria on the interior of your posterior.
A screen that does video processing often has some delay. Feeding the audio through the screen (even when you want to send it to a separate amplifier) has the advantage that the audio can be delayed by the same amount, so it is kept lip-sync.
When you feed audio to an amplifier and video to a digital TV separately, you will often find that the audio is visibly ahead of the video.
TFA states that the reason HDMI sucks is that it was based on the DVI standard. Then the summary goes on to say that "They reach back to the DVI standard to see what might be done to make HDMI a little more consumer-friendly, with numerous technical elements woven through the discussion." In addition, this whole article is pretty much about why twisted pair sucks for long cable runs compared to coaxial, and in the end of the article they advertise their new HDMI-cable whose pairs are molded together instead of just twisted together.
Let the jokes commence!
you mean not just for interior designers that have no clue about what constitutes a good viewing experience? The same interior designers that are in umpteen tv shows, avidly followed by your significant others, that think that the top of the fireplace is the best place for an HDTV? That also seem to think that it's perfectly fine to connect that 52" LCDTV with an RCA coax cable displaying SDTV because they have no clue about how to actually run a proper set of interconnects (or what a media server is, or the difference between 720p/1080i and 1080p)?
Next time you're talking with any of your married friends that are going to buy an HDTV, after a month or two ask them where they ended up putting it: if in the perfect place for best viewing, together with a good 5.1/7.1 system (good = costs at least as much as the HDTV, and must not be a bose), or if stuck 7 feet off the ground in their living room on top of the fireplace, so that you end up watching TV on the sofa at 90deg angle and craning your neck upwards to see something, and listening through the built-in 10W speakers.
-- the cake is a lie
As a physicist, it drives me nuts how much people are willing to pay for Monster cables or other "high-end" stuff. Need speaker wire? Just buy some heavy-gauge electrical wire. Home Depot sells 500 feet (152 m) of stranded 2-conductor 10-gauge (2.588 mm dia.) wire for about $85 USD. A similar length of thinner 12-gauge (2.053 mm dia.) Monster wire would cost a small fortune.
Some of you may note that, at 20 kHz (high end of human hearing range), the skin depth of copper is only about 0.47 mm, and so for high frequency, your conductivity will only scale with wire circumference, not area. That's true for solid-core, but keep in mind the Home Depot cable I mention is stranded, and has a 25% larger circumference than the Monster stuff. That should be more than enough to make up for any slight resistivity advantage the Monster cable might have from using purer copper (assuming they do).
What's really funny is the people who assume all this stuff matters for digital signals (as I saw in a few of the "reviews" on the Monster website). Unless you're stringing really long cables or your no-name stuff is really, really bad, there won't be a difference. Bits are bits, and small amounts of analog noise will be ignored.
Um no. you want a GOOD remote not a harmony or pronto.
get a universal MX-900 or a MX-950 or if you like flashey color displays and spending money get a MX-3000 color remote.
Those kick the crud out of the harmony, sony, merantz, pronto and other consumer remotes hands down. Plus you can get the RF gateway and hide all your gear behind doors or in a different room easily.
Dont get a harmony, you cant do decision based macros or variable tracking in them.
Do not look at laser with remaining good eye.
You can buy a 3ft HDMI cable for something like $4, 6ft for $6. Yes you can buy some ludicrously expensive HDMI cables but you can blame consumer ignorance and retailer greed for that. There is no reason to spend that much seeing as it is digital.
I see no reason at all to use component in an everyday situation if your device (be it a 360, PS3, DVD player etc.) and TV both support HDMI. It would be as dumb as connecting your PC to your monitor with VGA even when both have DVI-D support. The picture quality is far better over HDMI / DVD-D because it's digital. Analogue by definitiion degrades so even the best composite signal will still be worse than HDMI.
Your audio system doesn't switch video inputs for you? weird.
hdmi seems like a nice connector for outputs, maybe not inputs. like for DVDs, cableboxes, game consoles, media centers, etc. my TV set lets me plug in stuff into it and then will redirect the digital audio (or line-level audio) through an audio monitor port that i can then plug into an simple amplifier setup.
people with fancier AV systems can adjust volume and switch inputs of audio and video through the AV itself. and push out amplified signal to their speaker system with it. (prices start at about $200 for a very basic one)
“Common sense is not so common.” — Voltaire
FWIW my preamp has both depth and delay controls. I honestly thought all top-end systems had this till I looked around.
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
A friend of mine who works for a company that makes video processing and switching equipment has gone on and on about the problems with both DVI-D and HDMI is that there are very few manufactures that comply with them, and thus they are constantly having to update their processors to accommodate each different manufacturer's version of DVI-D and HDMI. It is the number one pain in their butts.
Of the two, HDMI is worse *because* of the DRM...the timing and buffering problems are almost insurmountable with some manufactures. I'm glad I don't have my friend's coding job! It would drive me bonkers!
ttyl
Farrell
CAN-CON 2019 - Ottawa's only book oriented Science Fiction Convention! October 18-20, Sheraton Hotel, Ottawa, Canada h
To be fair, some people like silver plated cables for corrosion resistance. I know I've seen older speaker cables have the exposed contacts corrode over time. I've never much worried about it (it's slow and my cables are still fine), but some do and that seems reasonable. I don't really know how much corrosion you'd have to have before it impacted the audio, though.
The solution for all these problems already exists. It's called the Serial Digital Interface. It's simple, cheap, and works over a single high-quality coax cable. It's used in professional video applications like television production and broadcasting. It doesn't do DRM, which I consider a feature. If you need to make a cable, just buy some Belden 1694A and a pair of 75-ohm BNC connectors.
Mea navis aericumbens anguillis abundat
Silver plating's also used for stranded wires with teflon insulation, since normal solder plating will melt and fuse the strands together at the temperature that the teflon is applied.
Anyone can "stand up for what they believe", but it takes a very brave individual to change what they believe. - Loundry
As another commenter already posted in another thread, they don't even stop when you're dead.
"We are Microsoft. You shall be assimilated. Competition is futile."
From the looks of things, this doesn't solve any of the issues with HDCP. From Wikipedia:
"DisplayPort connector supports 1 to 4 data pairs at main link that also carries audio and clock signals, with transfer rate of 1.62 or 2.7 gigabits per second."
As they're still talking about "pairs," I doubt the number one complaint voiced in TFA has been addressed.
"DisplayPort includes optional DPCP (DisplayPort Content Protection) copy-protection from Philips, which uses 128-bit AES encryption, with modern cryptography ciphers. It also features full authentication and session key establishment (each encryption session is independent). There is an independent revocation system. This portion of the standard is licensed separately."
Still has DRM.
In terms of long, have you ever tried to connect your receiver to a projector attached to the ceiling? You need a cable of about 30 feet or something. Bad thing. Loses sync all day long. It hasn't even been designed for _that_.
open (SIG, "</dev/zero"); $sig = <SIG>; close SIG;
With all the current cable types for a home theater system it makes the back of the receiver look like a pile of spaghetti. Not counting HDMI, or coax (cable-TV, not audio) the simplest connection is at least two cables, and some four or more.
I stumbled across an interesting proposal a few years ago called HAVi. Basically the concept is to use a single cable standard to communicate not only all audio, and video data, but also the ability for devices to communicate between themselves. To quote a section from the sites FAQ:
However, the last update to that website appears to have been sometime in 2004. Looking up information for this post I ran across what appears to be the current incarnation High-Definition Audio-Video Network Alliance (HANA) with some pretty heavy support from across the industry. Such as IBM, JVC, Mitsubishi Electric, NBC-Universal, Samsung, Sun, Texas Instrumets, WB, AMD, Dolby, ATI, just to name a few.
For those thinking that firewire (aka IEEE-1394-1995, IEEE-1394a-2000, IEEE-1394b, i.Link) has insufficient bandwidth for HD video signals let alone video & audio signals. Recall that Firewire as currently deployed can handle up to 800 Mb/s, and the spec currently allows for up to 3200 Mb/s, more than enough bandwidth for the content in MPEG2 format, let along h.264. Also note that the HANA proposal does not involve necessarily having the player decrypt the data, but possibly just transmitting the MPEG2, or MPEG4 singal along the cable, thereby reduce the amount of bandwidth needed. For a brief overview regarding why they choose firewire you can read an article
There's nothing inherently wrong with using twisted pair for this. You can run 10 gigabit Ethernet over 100 metres of twisted pair (granted, that's not in mass production yet), so why not a few gigabits of video? From my reading of the article, I think the real distance limitations on HDMI come from poor error correction and perhaps lack of self-clocking signals. And no, twisted pair Ethernet doesn't have such a high error rate that it requires many retransmissions. Retransmission is implemented at higher levels to recover from packet loss that mostly occurs at congested routers. On a single link the error correction code is adequate.