What's new

Coaxial or Optical Differences (1 Viewer)

Doug Lachman

Auditioning
Joined
Mar 5, 2001
Messages
8
Please excuse the dumb newbie question . . . I am in the process of upgrading my receiver from an old JVC prologic to a new Onkyo. The old receiver does not have either a coaxial or optical input for my DVD player, only RCA inputs. The Onkyo has both. Is there a difference between the two? What is the recommended connection? Please help, I am going out at lunch today to pick up the new receiver.
 
Joined
Jul 3, 2000
Messages
26
I'm no expert but I think you are better off using a good coax cable.
The main concern, I think, is if the optical connector is glass or plastic.
 

David Susilo

Screenwriter
Joined
May 8, 1999
Messages
1,197
Don't mean to be harsh here, but what does a search button do? To do a search for the very same question that gets asked for the umpteenth time!.
 

Reginald Trent

Screenwriter
Joined
Feb 18, 2000
Messages
1,313
I along with most others here feel there is no difference in sound quality between the two. The consensus seems to be go with the least expensive connector that best fits your needs.
BTW Dave, the search function is usally disabled due to the additional stress it puts on the server.
------------------
 

Hank Frankenberg

Senior HTF Member
Joined
Oct 13, 1998
Messages
2,573
Yeah David, that was a tad harsh. My experience is that for the last 10 times I've clicked on the search tab, I received the message that it was unavailable at the time for 8 of my attempts.
 

Mark Austin

Supporting Actor
Joined
Dec 28, 1999
Messages
639
quote: I along with most others here feel there is no difference in sound quality between the two.[/quote]
I must have missed the official poll on the subject. Do we really know if most others here feel that way?
I personally prefer coax on PCM mterial.
[Edited last by Mark Austin on July 11, 2001 at 08:55 AM]
 

Steve_D

Second Unit
Joined
Nov 28, 1999
Messages
299
I just researched and debated this subject.
Electronically speaking, optical is more subject to jitter according to research papers I've read. However, ALL decent DAC's have a crystalline based anti-jitter circuit that re-times the bitstream to remove jitter and it goes through this circuit whether the input is coax or optical.....though the quality of this circuit can and does vary somewhat as does the quality of the DAC's. Additonally, PCM is more subject to jitter (if it exists)than a packeted format like Dolby Digital or DTS.
Some "blind" tests claim to be able to consistenly hear the difference and claim coax is better. Others show no difference. I don't know nor can't attest to the exact methodologies of these tests. Most objective measurements show that if differences do exist they are well below the threshold of hearing (like -85 db or more).
Some people say yes they can hear a difference, some people say no. Some people believe in UFO's...some don't.
I'm not sure what I believe but I ordered a coax to go with my optical and I'm going to A/B them and decide for myself.
------------------
Link Removed
[Edited last by Steve_D on July 11, 2001 at 09:10 AM]
 

Louis M

Auditioning
Joined
Apr 11, 2000
Messages
3
Yes there is a difference. Optical is lower bandwidth than coax and more fragile.
As far as how they sound, optical is weaker on the bass region while coax is more balanced in sound.
If your system is on the Lo-Fi end, then you won't hear any difference. You must have a Hi-Resolution system in order to hear the differences.
Go to thewww.audioasylum.com for more specific details.
 

James D S

Screenwriter
Joined
Nov 14, 2000
Messages
1,000
quote: As far as how they sound, optical is weaker on the bass region while coax is more balanced in sound.[/quote]
Just the other night I heard this low-flying buzzing sound coming from overhead. I just knew it was a UFO! After going outside I realized that a neighborhood power transformer was on the fritz. Oh well.
[Edited last by James D S on July 11, 2001 at 03:24 PM]
[Edited last by James D S on July 11, 2001 at 03:25 PM]
 

Saurav

Senior HTF Member
Joined
Feb 15, 2001
Messages
2,174
It's true, I'm constantly amazed at what some people will believe in. Why, just the other day, someone was trying to convince me that the Earth wasn't flat!
While we're pressing buttons, I thought, why not :)
 

Reginald Trent

Screenwriter
Joined
Feb 18, 2000
Messages
1,313
I wrote:
quote: I along with most others here feel there is no difference in sound quality between the two.[/quote]
Mark Austin wrote:
I must have missed the official poll on the subject. Do we really know if most others here feel that way?
I personally prefer coax on PCM mterial.
[Edited last by Mark Austin on July 11, 2001 at 08:55 AM]
------------------------------------------------------------
Mark if you were to do a search.......
wink.gif
you'll find most of the people who post on this topic in the past support my statement.
BTW I also prefer coax if that make any difference to you. Also just because a difference between coax and optical can be detected in a lab does not mean it will be discernible in the real world by most people.
------------------
 

Mark Austin

Supporting Actor
Joined
Dec 28, 1999
Messages
639
quote: Mark if you were to do a search....... you'll find most of the people who post on this topic in the past support my statement.[/quote]
:) I haven't done a search, but I have been around here long enough to know that it's mainly the same people making the same arguments on both sides of the issue for a long time. I am also aware that most that post here have not taken the time to audition both at any extensive level. With 16,000 members I doubt we have heard anything but the most vocal, either way, at least in the threads I have seen.
quote: BTW I also prefer coax if that make any difference to you. Also just because a difference between coax and optical can be detected in a lab does not mean it will be discernible in the real world by most people.[/quote]
Preferences are just that, preferences. :) And I agree, with that statement about the lab, but conversely just because differences aren't detected in the lab doesn't mean they aren't discenable in the real world. I notice you throw in by "most people", and that is very true. Most people may not own the systems necessary to be able to discern those differences. But then again, MOST people don't have near the HT's that are found on this board.
[Edited last by Mark Austin on July 11, 2001 at 10:20 PM]
 

Reginald Trent

Screenwriter
Joined
Feb 18, 2000
Messages
1,313
It would probably be fair to say that most of the HTF members systems are probably not setup to the point of having the ability to audibly discern the difference between coax and optical.
------------------
 

Mark Austin

Supporting Actor
Joined
Dec 28, 1999
Messages
639
Reginald,
I'm not so sure of that. In my honest opinion, I would say that a fair amount of folks here have systems that could yield a discernable difference. I recently listened to some equipment at a friends house that wasn't overly elaborate. He had $800 mains, a $800 receiver, $300 dvd player, and we played around with some speaker cables and interconnects, and the differences were pretty noticable. I'm not saying that they were night and day, but they had a very discernable impact. I use a silver coax, and between that nd the copper you could hear the differences even listneing through his cable box.
 

Reginald Trent

Screenwriter
Joined
Feb 18, 2000
Messages
1,313
Even though many HTF memebrs have very high end setups I believe most of the 16,000 plus members do not. Just my opinion of course.
BTW If someone unbeknownst to you switched your coax with a optical cable would you immediately notice the difference?
------------------
 

Mark Austin

Supporting Actor
Joined
Dec 28, 1999
Messages
639
I will add this. We first tried the interconnect changes through his 12ga. Home Depot wire and the differences were much less noticable. Until we put in what I consider a mid- grade speaker cable, which was some Audioquest Indigo+, were the effects more discernable.
 

Reginald Trent

Screenwriter
Joined
Feb 18, 2000
Messages
1,313
Mark, I'm referring to switching the coax to optical of your system, not the speaker wireof your friend.
------------------
 

JakeG

Auditioning
Joined
May 7, 2001
Messages
4
Here's the thing I don't understand. I don't know how a difference can be heard, when it's just a stream of data going through the cable. It's not like it's streaming analog audio through the cable. The sound isn't even being "created" until it's inside the receiver. I'm not sure how you can hear less bass or whatever. I've never used an optical connection though, so I don't know first hand, but it SEEMS like they should be the same. Maybe someone can help me understand why they would sound different. Thanks.
___
Jake
 

Mark Austin

Supporting Actor
Joined
Dec 28, 1999
Messages
639
Reginald,
BTW If someone unbeknownst to you switched your coax with a optical cable would you immediately notice the difference?
I sure could, and I have tried it several times with friends doing the swtiching for me. It has a harsher, more compressed presentation, and it is very obvious on my regular rotation of discs. I spend up to about 5 to 6 hours a day listening to music, and once the songs become engrained in your mind a certain way switching to the optical connection is easy to tell.
Jake,
I'm talking about PCM material. With DD and DTS I have been unable to clearly pick out a difference. I'm not saying one doesn't exist, it's just very difficult with movie type material to make an accurate determination.
 

Saurav

Senior HTF Member
Joined
Feb 15, 2001
Messages
2,174
I don't know how a difference can be heard, when it's just a stream of data going through the cable.
That's where your understanding of the issues involved is a little flawed. If this were a computer downloading files from the internet, your statement would be correct. However, digital audio transmission is different from digital data transmission in one important aspect - the digital signal contains not only the data, but also the timing information. In a data transmission system, there is no timing information involved. In an audio system, the electronics at the receiving end recovers or reconstructs the timing from the signal. If there are errors in the timing of the incoming signal, this will have an effect on the sound produced.
You wouldn't see any difference if you just compared the bits going in to the bits coming out - they would all be correct (1s wouldn't have been converted to 0s or vice versa), and they would be in the correct order. However, the DAC in the receiver would have a harder time creating an analog signal out of those bits, because to create the analog signal, the DAC needs to know not just what value to generate, but also when to generate it.
So, there's your answer - not to why it should sound different, but to why it might sound different. Errors in timing information in a digital signal are known as jitter. The jury is still out on whether significant amounts of jitter exist in digital audio electronics or not, and even, how much jitter is "significant", i.e., what is audible. If you're interested in reading up on this, try http://www.digido.com/jitteressay.html), let's move on to the next stage in the discussion. The above explanation holds true for PCM data, but it doesn't really hold much water for DD/DTS signals. This is because those formats use packet/framing techniques, and these techniques are much less susceptible to timing effects than PCM. So, the argument shifts back to "there shouldn't be any audible difference".
As for less bass or greater tonal balance, I won't comment on that. You asked for an explanation of why there might be a difference between one digital audio bitstream and another, and that's all I am trying to discuss here.
 

Users who are viewing this thread

Forum statistics

Threads
356,451
Messages
5,113,014
Members
144,095
Latest member
zoobird
Recent bookmarks
0
Top