Interesting article for audiophiles - What's the Matter with HDMI?

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jqp

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rbrb

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Thanks for link.  The thing that still confuses me is consumers desire to get anything HDMI related.  Even a cheap ass $200 receiver has to be HDMI equipped these days.   

bpape

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Yup - because everyone has been officially 'scared' that copy protection will be implemented and if you don't have HDCP compliant HDMI, they'll either make content unavailable or down-rez'd to current DVD 480p.

Bryan

gooberdude

HDMI is the wolf in sheeps clothing for sure....     For most though, only having 1 cable for both and video?    sounds like a dream.



bpape

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It CAN work at some point - but not right now, at least not well.  Most of my customer use the HDMI for video and run separate audio and bypass any extraneous switching.  Many of the nicer processors geared toward the audio crowd don't even include HDMI.

Bryan

gooberdude

A few weeks ago i was at a party & guys were discussing tv's.   One guy blatantly said 'this new HDMI cable i got is awesome, blah, blah, blah'     As i was biting my tongue i grabbed the laptop and up popped half a dozen articles about the woes of HDMI and how it was an ill conceived connection...and passed it around for all to see.     

i'm always amazed at how disinformation spreads and spreads until it becomes the truth.   

samplesj

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Yup - because everyone has been officially 'scared' that copy protection will be implemented and if you don't have HDCP compliant HDMI, they'll either make content unavailable or down-rez'd to current DVD 480p.

I'm not sure this thread isn't playing just as fast and loose with the info as posters are claiming HDMI industry proponents are.  Its not about some magic 1 cable solution (although it is VERY nice).  And while I'm sure the whole copy protection is a big player in the decisions there are some things it offers that are new.

Some consumers want HDMI not just because it allows HDCP, but because there are VERY FEW displays that will take 1080p over anything else.  This means there is an automatic downgrade in source resolution to hookup a 1080p player with 1080p media to most 1080p displays via component.  Sure it will downrez to 1080i and then the display will scale back up, but you can't tell me you aren't losing data in that process.  Also keep in mind that most displays are now digital based so HDMI/DVI avoids an extra DAC/ADC step.  I didn't even really mention upscaling dvd players and their reliance on HDMI/DVI (with very few exceptions), because you can argue their scaler may or may not be better than the displays itself.

Now lets talk about the audio side of the fence.  Digital coax/toslink will not allow newer advanced (lossless) audio formats because they don't have the bandwidth, so you have to use analog outputs.  5.1/7.1 analog inputs provide much of the same features that running HDMI uncompressed LPCM does, but keep in mind that we've now got as many as 4 sets needed then (SACD, DVD-A, HDDVD, Blu).  Even if you ignore the multi-channel audio pieces you still have 2 hi rez players.  That means you need 2 sets of analog 7.1 inputs.  Also you are going to have the use whatever configuration options you have in that player which means less advanced bass management and no room analysis/equalization or you have to put it through an extra ADC/DAC step.  Don't forget that the analog outputs on Blu/HDDVD players are going to cost much more too.  The lower priced players don't have them now so you have to move up the chain.  For example a PS3 will do 1080p and full 7.1 uncompressed lpcm, but it ONLY works via HDMI (for both audio and video).


bpape

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Yup - because everyone has been officially 'scared' that copy protection will be implemented and if you don't have HDCP compliant HDMI, they'll either make content unavailable or down-rez'd to current DVD 480p.

I'm not sure this thread isn't playing just as fast and loose with the info as posters are claiming HDMI industry proponents are.  Its not about some magic 1 cable solution (although it is VERY nice).  And while I'm sure the whole copy protection is a big player in the decisions there are some things it offers that are new.

Some consumers want HDMI not just because it allows HDCP, but because there are VERY FEW displays that will take 1080p over anything else.  This means there is an automatic downgrade in source resolution to hookup a 1080p player with 1080p media to most 1080p displays via component.  Sure it will downrez to 1080i and then the display will scale back up, but you can't tell me you aren't losing data in that process.  Also keep in mind that most displays are now digital based so HDMI/DVI avoids an extra DAC/ADC step.  I didn't even really mention upscaling dvd players and their reliance on HDMI/DVI (with very few exceptions), because you can argue their scaler may or may not be better than the displays itself.

Now lets talk about the audio side of the fence.  Digital coax/toslink will not allow newer advanced (lossless) audio formats because they don't have the bandwidth, so you have to use analog outputs.  5.1/7.1 analog inputs provide much of the same features that running HDMI uncompressed LPCM does, but keep in mind that we've now got as many as 4 sets needed then (SACD, DVD-A, HDDVD, Blu).  Even if you ignore the multi-channel audio pieces you still have 2 hi rez players.  That means you need 2 sets of analog 7.1 inputs.  Also you are going to have the use whatever configuration options you have in that player which means less advanced bass management and no room analysis/equalization or you have to put it through an extra ADC/DAC step.  Don't forget that the analog outputs on Blu/HDDVD players are going to cost much more too.  The lower priced players don't have them now so you have to move up the chain.  For example a PS3 will do 1080p and full 7.1 uncompressed lpcm, but it ONLY works via HDMI (for both audio and video).



Yes - it down rez's because of the copy protection issue.  Yes, ANY time you go through a video conversion from progressive to interlaced and back, there are artifacts.

All of the information you cite about the bennies of HDMI are what has been forced on us due to copy protection issues.  The uncompressed only works on HDMI because they can turn it off at any time by setting the HDCP flag.  If you don't have a FULLY HDCP compliant chain, you get no signal. 

You should also look at the bandwidth capabilities of the HDMI cabling itself.  By the time you use the bandwidth requirements for 1080p video, I'll guarantee you there's LESS bandwidth available for audio than with an SPDIF connection.

Bryan

Bob in St. Louis

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  If you don't have a FULLY HDCP compliant chain, you get no signal. 

YES, When you purchase a piece of equipment, you expect it's going to work. I think that's a safe assumption. But when your "old" piece of equipment has a version of HDMI/HDCP that's different than your new piece has, you're screwed.
That's a CROCK in my opinion.  :evil:
At least Oppo has a good return policy since it wouldn't work with my projector that's about one year old. Technology shouldn't render an expensive unit useless when it's only a year old.

Bob - anti HMDI/HDCP. :nono:

samplesj

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Yes - it down rez's because of the copy protection issue.  Yes, ANY time you go through a video conversion from progressive to interlaced and back, there are artifacts.

All of the information you cite about the bennies of HDMI are what has been forced on us due to copy protection issues.  The uncompressed only works on HDMI because they can turn it off at any time by setting the HDCP flag.  If you don't have a FULLY HDCP compliant chain, you get no signal. 
It doesn't down rez because of copy protection on the disk, but rather because most displays won't take 1080p over component PERIOD regardless of what copy protection schemes the media and/or player have and/or support.  The hardware just isn't there to support 1080p over component for most displays.  We can gripe all we want, but it takes HDMI for 1080p for most people.  I'd rather get 1080p as long as all my gear supports HDCP vs not getting it at ALL.

You should also look at the bandwidth capabilities of the HDMI cabling itself.  By the time you use the bandwidth requirements for 1080p video, I'll guarantee you there's LESS bandwidth available for audio than with an SPDIF connection.
Please provide some sort of reference for the above.  This is an absurd claim.

The bandwidth is fine for HDMI and 1080p + 7.1 uncompressed.  Please do the math yourself before making that kind of claim. 

8 channels (7.1) of 24bit/192khz audio is 36.864 Mbps.  7.1 - 24bit/48khz is only 9.2Mbps.
1080p at 60hz with normal color is 4.46Gbps

Please notice how small the audio size is to the image size.  500:1?  It is really just noise in comparison.

From the HDMI site itself: "The DVI specification and versions of HDMI up through 1.2 support a maximum
single-link bandwidth of 165MHz per channel (4.95Gbps)."  That is PLENTY for 1080p/60hz and even 7.1 24/192 uncompressed pcm.

Once you go to HDMI 1.3 it doubles bandwidth so even 120hz is trivial.

Digital optical and coax cables in the format we use here max in the low single digit Mbps range (~3Mpbs). 
I'll give you this though.  If you are using a too long marginal quality cable you're going to have problems, but that isn't a problem with the spec, but rather that particular implementation of it.

MaxCast

Just got a new display.  Yes! one cable would be/is nice.  But my receiver doesn't have hdmi and I have to go through the receiver to keep source switching easy for the family.  Good thing Best Deal cables is having an awesome sale. 

Ears

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Yup - because everyone has been officially 'scared' that copy protection will be implemented and if you don't have HDCP compliant HDMI, they'll either make content unavailable or down-rez'd to current DVD 480p.

I'm not sure this thread isn't playing just as fast and loose with the info as posters are claiming HDMI industry proponents are.  Its not about some magic 1 cable solution (although it is VERY nice).  And while I'm sure the whole copy protection is a big player in the decisions there are some things it offers that are new.

Some consumers want HDMI not just because it allows HDCP, but because there are VERY FEW displays that will take 1080p over anything else.  This means there is an automatic downgrade in source resolution to hookup a 1080p player with 1080p media to most 1080p displays via component.  Sure it will downrez to 1080i and then the display will scale back up, but you can't tell me you aren't losing data in that process.  Also keep in mind that most displays are now digital based so HDMI/DVI avoids an extra DAC/ADC step.  I didn't even really mention upscaling dvd players and their reliance on HDMI/DVI (with very few exceptions), because you can argue their scaler may or may not be better than the displays itself.

Now lets talk about the audio side of the fence.  Digital coax/toslink will not allow newer advanced (lossless) audio formats because they don't have the bandwidth, so you have to use analog outputs.  5.1/7.1 analog inputs provide much of the same features that running HDMI uncompressed LPCM does, but keep in mind that we've now got as many as 4 sets needed then (SACD, DVD-A, HDDVD, Blu).  Even if you ignore the multi-channel audio pieces you still have 2 hi rez players.  That means you need 2 sets of analog 7.1 inputs.  Also you are going to have the use whatever configuration options you have in that player which means less advanced bass management and no room analysis/equalization or you have to put it through an extra ADC/DAC step.  Don't forget that the analog outputs on Blu/HDDVD players are going to cost much more too.  The lower priced players don't have them now so you have to move up the chain.  For example a PS3 will do 1080p and full 7.1 uncompressed lpcm, but it ONLY works via HDMI (for both audio and video).



Yes - it down rez's because of the copy protection issue.  Yes, ANY time you go through a video conversion from progressive to interlaced and back, there are artifacts.

All of the information you cite about the bennies of HDMI are what has been forced on us due to copy protection issues.  The uncompressed only works on HDMI because they can turn it off at any time by setting the HDCP flag.  If you don't have a FULLY HDCP compliant chain, you get no signal. 

You should also look at the bandwidth capabilities of the HDMI cabling itself.  By the time you use the bandwidth requirements for 1080p video, I'll guarantee you there's LESS bandwidth available for audio than with an SPDIF connection.

Bryan


Absolutely the exact opposite I am afraid Bryan.
The new codecs for hi res audio as well as PCM can only do two channels via SPDIF.

HDMI 1.1 or higher can do 1080p as well as multi channel PCM, DD-THD and  presumably DTS-MA via one cable.