Head-Fi.org › Forums › Equipment Forums › Cables, Power, Tweaks, Speakers, Accessories (DBT-Free Forum) › On HDMI, USB and Firewire super cables
New Posts  All Forums:Forum Nav:

On HDMI, USB and Firewire super cables - Page 2

post #16 of 46
Quote:
Originally Posted by kool bubba ice View Post
The whole HDMI thing is just a mess, they come out with too many versions to quickly.. 1.3 still has yet to be fully utilized yet.. Anyone remember 36bit deep color.. Now we are on 1.4, which makes our 1.3 receivers obsolete for the most part.. If you want to watch 3D movies with a 1.3 compatible receiver you will need a 3d BRP with 2 HDMI out puts.. You connect one to your display & the other to your receiver..It's getting silly.. It's going to take yrs before 1.3 is fully recognized, now they want to push out 1.4 due to the 3D rage.. 3D films are doing well, so they want to capitalize on it. I seen a 3D demo on a Panasonic plasma.. & it was amazing.. Much more realistic then the Samsung LCD.. But the glasses were uncomfortable.. Plus, the whole time I was watching the demo, all I could think of was gaming, not movies.. Imagine being chased by a 300lb DL men in Madden 2014 in 3D. The glasses cost 150 too..
Ever hear of backwards compatibility? The only difference with 1.4 cable-wise is for the optional ethernet and return audio features. 1.3 cables support 3D just the same. As for receivers, they should pass the video signal through unchanged and should not have a problem passing a 3D signal through--Regardless, most people can run one HDMI cable from each source to the display, and then one TOSLINK from the display to the receiver--No need for a player with multiple HDMI outputs (which I don't think they even make).
post #17 of 46
Quote:
Originally Posted by froasier View Post
Ever hear of backwards compatibility? The only difference with 1.4 cable-wise is for the optional ethernet and return audio features. 1.3 cables support 3D just the same. As for receivers, they should pass the video signal through unchanged and should not have a problem passing a 3D signal through--Regardless, most people can run one HDMI cable from each source to the display, and then one TOSLINK from the display to the receiver--No need for a player with multiple HDMI outputs (which I don't think they even make).
No such thing as a HDMI 1.4 cable.. Same with HDMI 1.0.1.1.1.2.1.3. It's the hardware that is 1.0-1.4 compliant.

The 3D Panasonic player has 2 HDMI outputs. I seen the player at BB..
post #18 of 46
Quote:
Originally Posted by kool bubba ice View Post
Quality HDMI cables come into play over long runs.. I heard of sparkling & white dots..
HDMI over 5m should run over optical anyway, MOLEX posted some scary measurements of the attenuation going on in a +5m copper HDMI cable..I'll try to find the link

EDIT: oops, it's a 404 now: http://www.molex.com/product/io/molexsi.html

figures were 0.78ms for a 2m cable and 17.04ns for 10m...there's also many problems like the skin effect, intra-pair skew, inter-pair skew, Far End Crosstalk(FEXT)...an HDMI cable is far from being "a bunch of 0 and 1"

some ppl seem to expect miracles, HDMI 1.3 is 340Mhz....over 40ft? yeah, right.
post #19 of 46
Quote:
Originally Posted by kool bubba ice View Post
No such thing as a HDMI 1.4 cable.. Same with HDMI 1.0.1.1.1.2.1.3. It's the hardware that is 1.0-1.4 compliant.

The 3D Panasonic player has 2 HDMI outputs. I seen the player at BB..
There is not a "1.4 cable" per se, but 1.4 supports ethernet and audio return channels, which require a souped-up cable specified in the 1.4 standard. These new cables, instead of being labeled by version number, will be labeled simply by speed and whether they have the ethernet support.

I haven't seen the Panasonic 3D player. Regardless, very few people need such a player as I explained above, and the 3D support is the mess, not HDMI versions. Even if you do need two HDMI cables, what's the big deal? It still beats the old four-cable system of component+S/PDIF.
post #20 of 46
I'm going to abandon thread. Apparently what I've seen cannot exist.

If you'll excuse me, I'm late for my trip to Loch Ness.
post #21 of 46
Quote:
Originally Posted by Duggeh View Post
I'm going to abandon thread. Apparently what I've seen cannot exist.

If you'll excuse me, I'm late for my trip to Loch Ness.
While what I've seen hasn't been nearly as bad as your experience, I have also seen similar issues with very long HDMI runs.
post #22 of 46
Here you go Guy. You know I trust Mattijs. If he says this braided configuration sounds better .... I believe him. I'll be giving it a spin when I go USB.

Pink Faun IL-2-USB kabel

post #23 of 46
yes, it braids the electrons...very clear sound!
post #24 of 46
Quote:
Originally Posted by GuyDebord View Post
In USB and Firewire the digital signal that gets transmitted via serial connections, a 1 and a 0 at a time, therefore, in order to provide error checking, flow control and to synchronize the devices, information is organised in the form of packets and frames. Its not an analogue signal yet, nor a single digital stream, therefore the only purpose the cables need to comply with is to transmit the data packets of 1's and 0's precisely. If a packet doesnt get transmitted precisely, it simply doesnt play it. Its just how it works.
Obviously you don't understand the difference between adaptive and async usb. Very few usb converters use the async method which allow error checking. Most adaptive usb converter stream real time data (audio) and are affected but what is called jitter (like spdif cables).
Line induced jitter (or jitter in digital cables) is a known and measurable phenomenon. Most of the attention has focused on measuring spdif and aes digital cable but the same principle apply for usb cables (on adaptive converters).
Jitter in digital cables can reach high levels as much as a few ns. You can read this research paper (http://www.iet.ntnu.no/courses/fe811...t_audiodac.pdf) or read this (Stereophile: A Transport of Delight: CD Transport Jitter).

Does it mean that line induced jitter is always audible? No, in most systems, it will be barely audible, you need a resolving system to hear the difference between 2 usb cables (when used with an adaptive usb converter). If the dac/amp/headphones are not resolving/revealing enough, a change in the usb cable will probably go unnoticed.
Also, it is better to spend money getting an async usb converter instead of spending one's money in a usb cable.

I hope my answer cleared some misconceptions. I have noticed that too often people confuse the way a hard drive and a usb converter work. While even the cheapest usb hard drive will never drop data nor will it be affected by the quality of the usb cable, it is different for an adaptive converter which are affected by the choice of the usb cable. FYI, more than 90% of the usb chips out there are adaptive and not async. From memory: the PCM270x, PCM290x, CM108, Tenor, ... all of them are adaptive usb and are affected by the jitter from the computer and the usb cable.

Edit -- It is funny how people who say that bits are bits always talk about 1's and 0's. In digital transmission (spdif/usb/...) there are no bunch of zeros and ones running around. What is being transmitted is an electrical square signal wave. That square wave can be affected (rounded off among other things) by the digital cable. What is important is not the data as much as the timing in spdif and adaptive usb.
post #25 of 46
Quote:
Originally Posted by slim.a View Post
That square wave can be affected (rounded off among other things) by the digital cable.
Sir, you win the thread.
post #26 of 46
Quote:
Originally Posted by ilney View Post
Sir, you win the thread.
I don't know if your post is ironic but I am going to be more explicit about the square waves.

Let us say we are transmitting a 12mhz square wave from the source to the receiver (it is what some call digital signal). Most digital cables (especially poorly design usb cables) will act as low pass filter at this kind of frequencies. Instead of having a pure square wave, we will have a square wave with rounded edges after the signal goes through the digital signal (low pass filter). The receiver side will use the edges to determine where those 1's and 0's are hiding. Of course, since it is "digital" you don't need a perfect square wave at the receiving end. However, the more distorted the square wave is the more jittery the result will be at the converter level. For those who have never seen square waves in the digital signal here are some examples :
http://www.sonicweld.com/scratch/div...terminated.jpg

http://usr.audioasylum.com/images/0/...-after_mod.jpg
post #27 of 46
"Sir, you win the thread."

+1

(@slim.a - nice SCI-FI btw.)
post #28 of 46
Quote:
Originally Posted by slim.a View Post
Obviously you don't understand the difference between adaptive and async usb. Very few usb converters use the async method which allow error checking. Most adaptive usb converter stream real time data (audio) and are affected but what is called jitter (like spdif cables).
Do you have a source to back up this claim? AFAIK USB always uses packets and error checking, async or not.
post #29 of 46
Quote:
Originally Posted by froasier View Post
Do you have a source to back up this claim? AFAIK USB always uses packets and error checking, async or not.
There are many articles talking about async vs. isochronous usb for audio.
As I said earlier most usb audio converters use the adaptive/isochronous method for streaming real time audio.

I did a quick research on google, and here is what I have found:

How USB Works

With isochronous data it is not possible to retry a failed transaction. Since only one ‘slot’ is allocated to the pipe during each frame, resending the data would delay transmission of the succeeding data samples, upsetting the time element of the data delivery. Consequently no handshake packet is sent and the data must be accepted ‘as is.’


Here is another interesting article that I found about usb audio on quick search:
6moons audio reviews: Wavelength Audio Brick USB DAC

You will see that jitter is a real problem in developping usb audio. That is why for example the PCM270x chips are limited to 3 frequencies (32kHz, 44.1kHz and 48kHz), it is mainly to reduce jitter.

So by deductive reasoning, you can understand that using a short and high quality usb cable will minimize data losses and jitter for isochronous devices.
Async usb devices are immune to the usb cable if they are properly designed.
post #30 of 46
LOL @ the article and the douch3 nozzle.
New Posts  All Forums:Forum Nav:
Head-Fi.org › Forums › Equipment Forums › Cables, Power, Tweaks, Speakers, Accessories (DBT-Free Forum) › On HDMI, USB and Firewire super cables