Digital Coaxial Cable Length Question

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I would like to replace the generic Toslink cable running between my streamer and DAC with a digital coax. I have 1m of Furutech Alpha Ag-75 cable and some Good quality RCA connectors (BNC not an option on my gear) to work with; however, I have read several places that digital coax cables should be a minimum of 1.5m to avoid signal reflections, timing issues. (Some have added that a very short length - under 1 ft - would also ameliorate such problems.)

Should I be worried about the length of the cable? Would I be better off constructing a short, < 1 ft. cable vs a 1m cable? Do I need to reconsider materials entirely?

Thanks for any guidance before I start.

Paul
 
Sounds like nonsense to me, if the cable is properly terminated with 75 ohms its length only affects the attenuation, which is negligible with the frequencies in question.


"Digital coax" - you mean "coax". Standard high quality 75 ohm coax as used for video cables is just fine here, snake oil is not needed!


By the way the only property of the RCA connectors that matters is their RF impedance continuity, which is not guaranteed by spending money, but chosing a part designed for high frequencies using sound RF engineering principles.
 
I think this idea originated with a now-banned DIYA member called Jocko Homo. He did have some considerable RF engineering chops. His thinking I believe was that if reflections arrive about one bit-time later then the receiver's going to be subject to more jitter. Given the use of RCAs rather than BNC, some reflections are going to be pretty much inevitable so it would be better to move them out of the way, timing-wise. Trouble is - even longer cables can end up with reflections occurring around subsequent bit transitions so I'd not worry too much in practice how long your cable is.
 
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