Soldato
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What about if interfences takes a 0 to 0.1Volt, would it then be considered as a '1'
Which HDMI lead?
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What about if interfences takes a 0 to 0.1Volt, would it then be considered as a '1'
Man of Honour
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That's why digital interfaces have things like check-bits and the like.
Soldato
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Ok you have to look at this technical graph by russ andrews, it has labelled axes and lines of best fit. Almost looks like a materials stress vs strain graph from my degree.
o wait, read the bottom bit that is cut off from the pic but in small print on his website
I think they should be made to state on these things that "this graph is completely meaningless". RA have been in trouble in the past due to false claims, i'm surprised they're still allowed to trade.
It would be interesting to hear thier take on the fact HDMI has a fixed specification, like CAT5 cable, unless it meets certain requirements it cant be classed as an HDMI cable. I found the below sepecifications on wikipedia, now to try and figure out how those figures stack against the actual bandwidth requirements for HD video.....anyone happen to know?
HDMI version.........................................1.0–1.2a...........1.3+
signal bandwidth (MHz) ..................................165..............340
TMDS bandwidth (Gbit/s).................................4.95............10.2
video bandwidth (Gbit/s)..................................3.96............8.16
audio bandwidth (Mbit/s).................................36.86..........36.86
Color Depth (bit/px)...........................................24............48[A]
resolution over single link at 24-bit/px....1920×1200p60....2560×1600p75
resolution over single link at 30-bit/px[C]...............N/A........2560×1600p60
resolution over single link at 36-bit/px[D]...............N/A.........1920x1200p75
resolution over single link at 48-bit/px[E]...............N/A..........1920×1200p60
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It is a graph and thus is technical, but they do have this below the picture:
The graph is only a small thumbnail at the top of one of the pages, but still useless and makes me think even less of Mr snake oil.
From his graph, everything in the lower left is near 0,0 so should be really crap, and anything top right must therefore be amazing. He really needs to get it right even with a made up useless graph.
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Then that bit would fail its checksum authentication, depending on equipment the reciever would then either re-request the same bit or it would correct it (1.1V is 99% likely meant to be 1.0V and not 0V) or ignore it entirely.
If you have a HDMI cable that you made yourself from old coathangers I reckon you will notice a definate degradation in image and sound quality, it'll be like trying to watch a corrupt AVI, you'll say "hmm this isnt right."
If however you have paid a fiver or whatever for a cheap cable using reasonable copper for each connection with resonable silver foil wrapping to stop at least 90% of interference then i can almost guarantee you will see no difference at all, and indeed hear no difference. you will be recieving at least 99% of all bits error free.
I think its shocking that cable companies have managed to push off digital cabling under the same premise they used to sell analogue cabling... i find it even more suprising that reputable magazines go for it.
When was the last time you thought "oh no i wonder if my SATA cable is of good enough quality copper, maybe id better go and pay £100 for one from Monster cabling"... I dont think many people ever have, and yet our optical and hard disk drives keep managing to transfer binary data around with near perfect accuracy inside a metal box crammed full of EMI emitting electronics... amazing!
Maybe The graph is right, but in order for it to really make sense you have to rename the "y" axis with "price per meter" and the "X" axis with "ammount of exotic materials and finishes used"
Soldato
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well, 1080p/60 is 3.96Gbit/s which is what 1.2 was capped at. 1.3 is capable of a whole lot more
Soldato
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Maybe The graph is right, but in order for it to really make sense you have to rename the "y" axis with "price per meter" and the "X" axis with "ammount of exotic materials and finishes used"
Correction, the X axis represents % profit to be made
Soldato
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oh i just spent £10 on a 10m hdmi lead. its PERFECTLY fine btw