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PerfectWave I2S HDMI cable claims don't make sense to me

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I just don't buy the hype. With analog cables I can see the value of cables designed and built to deliver a signal as close as possible to the original. Analog signals are altered by cable capacitance and inductance, as well as resistance, and RF in the environment can alter the waveform.

But digital signals are a completely different beast. As long as the signal reaching the receiving device is strong enough to deliver a signal the receiving device can use, why care if the cable has slightly more or less resistance (silver versus copper conductors)?

When an analog signal is altered, it's called distortion. The worse it is, the more general degradation we hear in the sound or see in a picture. Small amounts of distortion may be unnoticeable to most people, as with an amp that has 0.05% THD, or a slight decrease in video saturation.

But digital signals don't get "distorted." They're either exactly as the original or they're corrupted. A corrupted digital signal is not just going to make audio sound a little degraded or make video less "three dimensional." Corrupt a digital signal, and *if* the receiving device can use it, the effects will not be subtle. Video will not be less sharp, or less "three dimensional," it will have noise in it. I have an 18" HDMI cable connecting my Blu-ray player to my processor, and a 15' HDMI cable from there to my 1080p HDTV. These are the cheapest cables I could find. There is no video noise, and the picture is exceptional in every way, as is audio from Blu-ray, CD, and SACD. So all evidence suggests that the little bits are getting to their destination just fine.

Follow Ups:

RE: PerfectWave I2S HDMI cable claims don't make sense to me - PaulMC 05:57:26 07/29/09 (4)
While this is an interesting argument I'll have to add something you may not have considered. Jitter and timing to the digital signal. Today's digital devices use edge triggering to read the data. Cables change the rise time of the edges, and they do so in uneven ways depending on the frequency. When the rise time changes the angle of the slope changes and this means that the threshold of the edge changes in time. So as the signals come down, the point in time where they are recognized as a 1 or a zero moves with varying rise times and this causes the signal to be jittered. I don't have time this morning to go into depth but this is just one (major) way a cable has a significant effect on the way digital "sounds". Trust me, it's not hype.
- RE: PerfectWave I2S HDMI cable claims don't make sense to me - skytag 04:30:36 07/30/09 (3)
  Somehow I have serious doubts that the amount jitter introduced by what you describe in a few feet of HDMI cable would would even come close to being detectable by the human eye or ear. Plus, I would expect jitter in the devices in the chain -- player, processor, and in the case of video, the TV -- to far, far exceed anything introduced by 3' or 6' of HDMI cable. So while it might be an issue at a theoretical level, I can't imagine the benefit I'd get from spending $1000+ (output from source and output from processor for video) would even be detectable, much less give me real bang for the buck over the less than $15 I have invested now.
  - RE: PerfectWave I2S HDMI cable claims don't make sense to me - PaulMC 05:49:39 07/30/09 (2)
    Understood. You'll just have to see what you think if you have the chance.
    - RE: PerfectWave I2S HDMI cable claims don't make sense to me - nabizko 01:45:18 05/31/10 (1)
      I have to agree. Digital is not variance in voltages which means, there are no variations of the original signal...there's just the 0's or 1's and there's only one way to interpret each as a 1 or a 0! If you're running HDCP, then you can guarantee that the reciever is getting 100% original signal, sort of like parity checking...That's how digital works. 16-24bits...of 0's or 1's not kinda a 0 or kinda 1. it's either or. NOW, if you happen to be missing a 0 or a 1, then yes, you have a corrupt signal, in the pc world, this becomes unusable data...or you hear a dramatic hiccup or pop, or digital noise. This isn't acceptable by any means, no one can convince me this is a common occurance, or no one would use digital. So once again, explain to me...HDMI is a a digital bus that carries a digi signal, you can't have loss or you don't have a signal...so forget that. but to have a bus that can manipulate the digi signal b4 it reaches the the other dsp isn't just a bus then. It's not just carrying the signal...on a pc mainboard...you have a northbridge that serves as a traffic cop between the ram, cpu, pci-e, and southbridge (before i7 it was also the mem controller as well) the fsb wasn't dictated by the wires between the nodes, it was dictated by the nodes. In this situation, the BD-player and the dsp in the TV.
      - RE: PerfectWave I2S HDMI cable claims don't make sense to me - PaulMC 05:57:13 05/31/10 (0)
        
        In Reply to: RE: PerfectWave I2S HDMI cable claims don't make sense to me posted by nabizko on May 31, 2010 at 01:45:18
        
        It's the old "bits are bits" argument that has been around for a long time. What you have to remember is that bits are just bits but there's much more to the story than just reading ones and zeros. There are timing issues, extracting clocks, etc. Digital isn't the simplistic clear cut format you describe.
        
        Do a search for Robert Harley's great article on why identical digital data sounds different. It's well thought out, technically accurate and will help you understand.

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