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A comment on Why you should never pay more than $10 for an HDMI cable (Infographic). Parent comment

Re:Why you should never pay more than $10 for an HDMI cable ... by micks56 on Wednesday March 31, 2010 @10:46AM (#1231895)
But the reason why your digital TV shows the correct screen is because the cable transmitted the "digital" bits between your DVD player and the TV correctly. If you have a poorly made cable you will get bit errors. Electromagnetic interference from other A/V equipment could also cause bit errors. A well made cable with twisted pairs, proper shielding (few people do this correctly), and well formed connector crimps will prevent those bit errors. With bit errors, what your awesome Blu-Ray player decodes off of the Blue-Ray disc will not be what is shown on the screen (assuming there isn't bit error correction in the TV, etc.).

And your speakers are playing an analog signal. Cable quality matters even more there.

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Re:Why you should never pay more than $10 for an HDMI cable ... by oostevo on Wednesday March 31, 2010 @11:08AM (#1231955)
Yup, the correct signal might not get through if you don't have perfect shielding. And a speck of dust on a CD could theoretically ruin a whole song.

That's why CDs (and cellphones, modems, and countless other digital devices) use channel encoding.[1] That way you don't have to have a perfectly noise-free signal to reconstruct the original information.

I don't know that many specifics of the DVD or Blu-Ray standards, but I'd put money on them using Reed-Solomon or something similar.

[1] http://en.wikipedia.org/wiki/Reed-Solomon_error_correction#D...

(Edit: forgot footnote)

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Re:Why you should never pay more than $10 for an HDMI cable ... by mseebach on Wednesday March 31, 2010 @11:05AM (#1231944)
> But the reason why your digital TV shows the correct screen is because the cable transmitted the "digital" bits between your DVD player and the TV correctly. If you have a poorly made cable you will get bit errors.

Yes. Which is why the poorly made cable can be said to not work.

> And your speakers are playing an analog signal.

Huh? I've never heard of HDMI cables capable of carrying analog sound.

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