How long are your digital cables? (S/PDIF, AES/EBU, USB, etc.)

[House de Kris]

It would appear that most of my coax SPDIF cables are in the 3ft neighborhood. I have one 6 footer. As I understand it, the concern here is about reflections on the cable. With RCA terminated SPDIF cables, it is pretty much guaranteed there will be plenty of reflections. A BNC terminated SPDIF should be free of reflections (assuming the equipment makers know what they're doing - which I feel is a safe assumption). The sweet spot of 1.5m for an SPDIF cable seems, to me, to be Internet-lore. Different cable constructions will result in different propogation speeds, thus making the magic number different for different cables. I really don't think it is one size fits all.

I've also got an AES/EBU cable that is only 6" long. Although I've never measured it, I seriously doubt the XLR connector is designed as a controlled impedance connector, so it too would be a cable worthy of a magic length. I doubt mine even has 110ohm cable in it. Doesn't really matter in my application, as it goes between an ADC and a recorder, thus making the importance of reflections moot.

[G8YU]

I try to keep my digital cables between 1.5 to 2 meters. This isn't just for reflection reduction; it seems to be the most useful length for me, especially for USB. A two meter USB gave me plenty of location options without excess cable laying around. The 1.5 meter I use now is just barely long enough. They are different brands so a comparison concerning length isn't fair.

I have a few lengths of optical cable, WireWorld Supernova 6 and 7. I think I compared a 2 meter to a 3 meter (or maybe it was a 1.5 and a 3 meter). Anyway, I didn't notice a difference in sound quality. I have an 8 meter Supernova 6 and have never had any problems with it. I haven't compared it to a shorter length. The only difference I've heard is when I got a 2 meter Supernova 7 to replace an old 6 generation. From what I remember there wasn't much difference in detail or frequency extension. It was the PRAT factor that noticeably increased (my involuntary foot tapping was a clear indication). I guess that's an indication of reduced jitter in the connection.

[Orb]

Originally Posted by House de Kris

It would appear that most of my coax SPDIF cables are in the 3ft neighborhood. I have one 6 footer. As I understand it, the concern here is about reflections on the cable. With RCA terminated SPDIF cables, it is pretty much guaranteed there will be plenty of reflections. A BNC terminated SPDIF should be free of reflections (assuming the equipment makers know what they're doing - which I feel is a safe assumption). The sweet spot of 1.5m for an SPDIF cable seems, to me, to be Internet-lore. Different cable constructions will result in different propogation speeds, thus making the magic number different for different cables. I really don't think it is one size fits all.

I've also got an AES/EBU cable that is only 6" long. Although I've never measured it, I seriously doubt the XLR connector is designed as a controlled impedance connector, so it too would be a cable worthy of a magic length. I doubt mine even has 110ohm cable in it. Doesn't really matter in my application, as it goes between an ADC and a recorder, thus making the importance of reflections moot.

Yeah totally agree with you, strange how BNC never really took off in the domestic audio world.
What also compounds reflections is the transmission and receiver chips or design implemented in the audio hardware.
So I would say the general rule is roughly 1.5m to 2m rather than shorter.
That said I use 1m often myself doh

AES/EBU should still be better than RCA in terms of general design-considerations for digital; seems this is also the consensus with the known engineers on forums such as diyaudio; but again implementation is always the trump card.

Cheers
Orb

[Rod#S]

Well I decided to go against the collective wisdom of minimal length. Seeing as the extra half meter 1.0 -> 1.5 was not an insignificant amount of money it's just a hard pill to swallow when you know you don't physically need the extra length to get from component A to B. So it came down to a cost vs possible slight performance advantage decision.

[Mr_Sukebe]

Zero. As per Dan, I use a streamer that doesn't need SPDIF and thus avoids the associated jitter.