Coaxial vs optical vs HDMI - which is the best audio connection to use?

daddyo

Active member
Nov 7, 2021
11
1
25
Visit site

This is a very well written article for neophyte audiophiles like me. Specific comparison with just enuf practical technical information. A couple of yrs ago a "professional installer" used coaxial cable to connect my 5.1.2 system and I had difficulty convincing him that coax wasn't suitable for that application. It took extensive internet searches to gather the info that this article provides in a succinct manner. Well done.
 

spk

Member
Feb 4, 2022
4
1
20
Visit site
to be frank, it seems so strange that in this day an article with so many misconceptions would be written. Not only can optical support 192k bandwidth (was literally listening to a 192k FLACC over optical when I read this) that wouldn’t have any affect whatsoever on streams at a lower sample rate. It isn’t like the bits are frolicking more freely in copper, making those treble notes more sweet.

furthermore the question of interference; because the signal is Digital it’s either there or it isn’t. While some massive amount of interference might potentially flip a low bit to a high bit, if you have that level of interference in your system then something else is certainly very, very wrong, and your cable choice is the least if your worries. If such digital interference is audible, it’s going to completely wreck the stream - not just some sort of subtle effect - that’s how digital works, it either is or it isn’t.

While 20 years ago these sorts of misconceptions about digital signals were understandable, today it should be common knowledge that digital interference is not the same as analog interference and behaves completely differently.

Now I think the biggest advantage of coaxial over consumer optical is that coaxial is will work better over distances greater than ten feet, though I could be wrong about that.
 
Last edited:
  • Like
Reactions: Venzer

Nick_B

Active member
Mar 13, 2022
5
2
25
Visit site
to be frank, it seems so strange that in this day an article with so many misconceptions would be written. Not only can optical support 192k bandwidth (was literally listening to a 192k FLACC over optical when I read this) that wouldn’t have any affect whatsoever on streams at a lower sample rate. It isn’t like the bits are frolicking more freely in copper, making those treble notes more sweet.

furthermore the question of interference; because the signal is Digital it’s either there or it isn’t. While some massive amount of interference might potentially flip a low bit to a high bit, if you have that level of interference in your system then something else is certainly very, very wrong, and your cable choice is the least if your worries. If such digital interference is audible, it’s going to completely wreck the stream - not just some sort of subtle effect - that’s how digital works, it either is or it isn’t.

While 20 years ago these sorts of misconceptions about digital signals were understandable, today it should be common knowledge that digital interference is not the same as analog interference and behaves completely differently.

Now I think the biggest advantage of coaxial over consumer optical is that coaxial is will work better over distances greater than ten feet, though I could be wrong about that.

Hey SPK this thread was kind of timely for me.
Not sure if you have an opinion on this but:
I have a panasonic ub9000 dvd player which I also use for cds, and a yamaha RX-A2080 av amp.
Question is -- is it 'better' to use the DAC in the player, or the DAC in the receiver for CD playback? Assuming they're broadly similar, my thought was, do the conversion close to the source but I'm a total noob so that could be nonsense.
If better to use the receiver; I have an optical cable already. I take it from your opinion that there shouldn't really be anything in it between that and a similar quality coaxial cable? (makes sense to me).
If better to use the panasonic dac, then should I go ordinary analogue interconnects, or the balanced pin cables? why?
Might be I'm overthinking it all at the 'level' of equipment i have...so if you say 'just run what you have' I get it too... :)
Cheers
 
  • Like
Reactions: spk

spk

Member
Feb 4, 2022
4
1
20
Visit site
Hey SPK this thread was kind of timely for me.
Not sure if you have an opinion on this but:
I have a panasonic ub9000 dvd player which I also use for cds, and a yamaha RX-A2080 av amp.
Question is -- is it 'better' to use the DAC in the player, or the DAC in the receiver for CD playback? Assuming they're broadly similar, my thought was, do the conversion close to the source but I'm a total noob so that could be nonsense.
If better to use the receiver; I have an optical cable already. I take it from your opinion that there shouldn't really be anything in it between that and a similar quality coaxial cable? (makes sense to me).
If better to use the panasonic dac, then should I go ordinary analogue interconnects, or the balanced pin cables? why?
Might be I'm overthinking it all at the 'level' of equipment i have...so if you say 'just run what you have' I get it too... :)
Cheers

so assuming that the dac is equal in quality i would convert at the receiver. I could be mistaken, but my impression is that analog signals, especially unbalanced, low level signals, are susceptible to noise whereas digital signals, especially optical, are not. So you want to keep your analog signal path as short as possible.

Also, think of your DAC as the source, not the player (transport) since the DAC is the source of the analog signal. So in this mindset keeping your source in close proximity still applies.
 

Nick_B

Active member
Mar 13, 2022
5
2
25
Visit site
Sweet, thanks for that. I *THINK* it sounded subtly better using the receiver dac anyway, but wasn't sure. Good to have a rational explanation for it tho. cheers.
 

spk

Member
Feb 4, 2022
4
1
20
Visit site
Sweet, thanks for that. I *THINK* it sounded subtly better using the receiver dac anyway, but wasn't sure. Good to have a rational explanation for it tho. cheers.

This alone likely will not matter much, but this is, in my opinion, your best practice. with analog everything is cumulative, a lot of little things will tend to add up, so its best to get as much right as practical, at least within reason.
 

ginandbacon

Member
Apr 4, 2022
2
0
20
Visit site
They could easily update both to support full bandwidth, all formats but it's all about HDCP, which is a shame. Also, maybe Toshiba invented the original digital toslink connected but both are S/PDIF, which was created by Sony and Philips.(see below).

It's a shame because there is no way that can convince me that gig fiber internet and 4K SDI connectors exist but somehow neither can be updated to support maybe 5 to 10Mbps (500KB/s or 1MB/s because your typical 7.1 Atmos bedded in a Dolby TrueHD signal isn't possible (Atmos isn't a sound format, it's metadata embedded in a DD+ or Dolby TrueHD signal, both which have been around since Blu-Rays came out. Heck, they used unused CEC bandwidth originally to do ARC. My highest bitrate music is SACD and it's typically 4 to 6Mbps for 5.1 actually remastered for 5.1. I just don't get it because, while I would never condone it. HDCP doesn't protect anything. It's out there if you want. Now, I purchase or subscribe to services for my music/movies to support them but it's not like HDCP is really protecting anything.

S/PDIF (Sony/Philips Digital Interface) is a type of digital audio interface used in consumer audio equipment to output audio over relatively short distances. The signal is transmitted over either a coaxial cable with RCA connectors or a fiber optic cable with TOSLINK connectors.
 

ginandbacon

Member
Apr 4, 2022
2
0
20
Visit site
so assuming that the dac is equal in quality i would convert at the receiver. I could be mistaken, but my impression is that analog signals, especially unbalanced, low level signals, are susceptible to noise whereas digital signals, especially optical, are not. So you want to keep your analog signal path as short as possible.

Also, think of your DAC as the source, not the player (transport) since the DAC is the source of the analog signal. So in this mindset keeping your source in close proximity still applies.

Pretty much this outside the fact that almost all HDMI cables shorter then 10 to 15ft max are copper. Really, you just need a well shielded cable although it's always a good idea to keep all cable runs as short as possible in my experience.

Even fiber HDMI cables typically have 2 to 4 copper wires, which is why they are still shielded. Pretty sure toslink is no metal outside the connections, which are often plastic also. Noise is hard to pin down sometimes because it depends on your house/apartment wiring, potential ground loops, ECT...

If you ran everything off battery that pretty much elimates most noise but that would be crazy expensive. Even high end sinewave AV battery backups can't keep a system up that long. This will 9bviously depend on the setup and power used. It would not be crazy expensive to keep a DAC, 100W amp going to passive speakers up on a sinewave battery but 500W amp and other power hungry equipment will drain the battery quickly.

It also has to be implemented correctly so it's always running of battery. Many claim they do but in reality they really don't. Sinewave batteries can just produce stable clean power when done correctly, which is often very expensive.
 

TRENDING THREADS

Latest posts