mrehorst
Super Member
That's hardly twisted at all! If you want to really twist wires, you need one of these:
Coax vs optical...
- Thread starter Mitko 55
- Start date
There is a couple of documents that could be useful if it's determined that a custom cable is desired. I have plenty to learn when it comes to S/PDIF or AES.
Grounding and Shielding Audio Devices
Since the Audio Engineering Society has adopted the "pin 2 is hot" standard, what is the correct use for pin 1?
www.ranecommercial.com
Sound System Interconnection
RaneNote 110 explains the cause and prevention of ground loops and how to interface balanced and unbalanced gear with proper connections and wiring.
www.ranecommercial.com
I noticed that optical sounds better with more detail and better intelligibility at lower volumes, but I prefer digital coax for its richer and fuller sound at normal listening volumes. Digital coax can pass greater bandwidth it seems. I am getting a max bandwidth of 24-bit / 96kHz audio over optical (through the use of an HDMI audio extractor) that sometimes can go as high as 24/192, but the stars have to align just right, otherwise it doesn't happen. I can't "make" it pass 24/192 when I want to -only when it wants to. On the other hand, coax will pass that same signal as 24/192 consistently and without issue which makes it the better all-around choice. One thing that sucks about optical is that most optical cables have plastic connectors at the end, and most optical jacks are plastic as well. This means the optical connection is mostly droopy due to the weight of the optical cable and has way too much 'flex'. It bugs me, so I find optical cables with metal connectors, but then the mating jacks are always still plastic and too difficult to upgrade. The optical connection always seems very shoddy and loose.
** Another interesting (and unfortunate) thing is that many Smart TVs have an optical out, but not a digital coax out for some reason. What this means is that you can have a 24/192 audio signal being fed through something like an Amazon FireStick 4k Max through your TV's HDMI ARC/eARC input that will show as "track quality" 24/192 onscreen through the Amazon Music Unlimited app, but it always comes out as "being played at" or "system capability" of 24/48 through the optical out of your TV. It's extremely annoying and frustrating. When this happens, it means you need to purchase (and connect) an external HDMI audio extractor to get the advertised bandwidth that's going in to the TV but not coming out of it. Preferably, the extractor has coax out as that is the more robust option that seems to reliably pass the higher bandwidths without fighting and downsampling them constantly (or leaving it to chance) when compared to optical, but only about 5-10% of splitters come with coax out. Usually they only come with optical or HDMI out (eARC) for multi-channel.
It has taken me many, many hours of trial and error/ frustration/ customer support with various brands of audio products to figure this all out. You're trying to figure out which component in your signal chain is to blame and it's maddening and takes some serious dedication and sleuthing to figure out. It mostly seems to be an inability of Smart TV's themselves not being able to output the same audio resolution they're being fed with the provided audio output jacks they're made with. At some point, the TV tries to downsample the audio that comes out of it, even though in your head you're thinking the digital signal is not being internally processed within the TV and is just being passed through "as-is" since it's digital and the TV is merely acting as a "transport" from I/O. This is apparently not the case and makes a lot of unnecessary work for the consumer (on the back-end) to figure this all out on their own time since nobody explains why this consistently happens with many (or most) TVs. The video resolution capabilities of a TV always greatly supersede its audio abilities I've found. The digital audio output part is just an afterthought that seems cobbled together last-minute and doesn't work right.
** Another interesting (and unfortunate) thing is that many Smart TVs have an optical out, but not a digital coax out for some reason. What this means is that you can have a 24/192 audio signal being fed through something like an Amazon FireStick 4k Max through your TV's HDMI ARC/eARC input that will show as "track quality" 24/192 onscreen through the Amazon Music Unlimited app, but it always comes out as "being played at" or "system capability" of 24/48 through the optical out of your TV. It's extremely annoying and frustrating. When this happens, it means you need to purchase (and connect) an external HDMI audio extractor to get the advertised bandwidth that's going in to the TV but not coming out of it. Preferably, the extractor has coax out as that is the more robust option that seems to reliably pass the higher bandwidths without fighting and downsampling them constantly (or leaving it to chance) when compared to optical, but only about 5-10% of splitters come with coax out. Usually they only come with optical or HDMI out (eARC) for multi-channel.
It has taken me many, many hours of trial and error/ frustration/ customer support with various brands of audio products to figure this all out. You're trying to figure out which component in your signal chain is to blame and it's maddening and takes some serious dedication and sleuthing to figure out. It mostly seems to be an inability of Smart TV's themselves not being able to output the same audio resolution they're being fed with the provided audio output jacks they're made with. At some point, the TV tries to downsample the audio that comes out of it, even though in your head you're thinking the digital signal is not being internally processed within the TV and is just being passed through "as-is" since it's digital and the TV is merely acting as a "transport" from I/O. This is apparently not the case and makes a lot of unnecessary work for the consumer (on the back-end) to figure this all out on their own time since nobody explains why this consistently happens with many (or most) TVs. The video resolution capabilities of a TV always greatly supersede its audio abilities I've found. The digital audio output part is just an afterthought that seems cobbled together last-minute and doesn't work right.
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zenith2134
Lunatic Member
Pick your poison, optical is impervious to induced emf on its line, but can be limited to 96kHz depending on the chipset. I have always preferred coaxial, but I use analog primarily so, I may not be the best resource here. Just basing it on my reading and what I've heard.
mrehorst
Super Member
I don't know how there could be any differences in optical vs coax that would affect intelligibility at any volume level.
Toslink optical has limited bandwidth- that's why the TV output is limited to 24bits/48 ksps via optical. That is why it is preferential to use an HDMI out from the TV to get full BW audio. If you use HDMI eARC you can get multichannel audio which you can't get via optical (because of limited BW).
1. jitter was a solved issue decades ago
2. a short cable wont cause jitter
3. any inaudible jitter is nulled by many modern dacs, even cheap ones, like say a $80 smsl su-1
4. reported differences vanish like a fart in the wind when put to a controlled test
5. even if the above was not true it would still be the absolute least meaningful parameter in any system by far
iv heared people talk lavishly about how much better one out of 2 dacs sounded, without knowing they listened to the same dac twice.
all these types of subjective reports have worked wonders for the bank accounts of snakeoil brands and salesmen for decades, even better now because of the internet. then ASR showed up and they are pissed.
2. a short cable wont cause jitter
3. any inaudible jitter is nulled by many modern dacs, even cheap ones, like say a $80 smsl su-1
4. reported differences vanish like a fart in the wind when put to a controlled test
5. even if the above was not true it would still be the absolute least meaningful parameter in any system by far
iv heared people talk lavishly about how much better one out of 2 dacs sounded, without knowing they listened to the same dac twice.
all these types of subjective reports have worked wonders for the bank accounts of snakeoil brands and salesmen for decades, even better now because of the internet. then ASR showed up and they are pissed.
Was the analog output stage the same?
Oasis8
Well-Known Member
Measurements have been around a lot longer than ASR, so you may be overstating their relevance.
AudioAvarice
Super Member
Oh look another ASR cultist has come to show us the light, it's okay, he has his lumen meter.
Mart Mccall
Well-Known Member
What he says about jitter is absolutely correct. We can potentially hear timing errors down to nanoseconds but even the first CD players had DACs with timing errors down to picoseconds. That's two orders of magnitude lower. Jitter has never been an audible issue. Anyone who claims it is is either misinformed or trying to sell something.
Oasis8
Well-Known Member
Most people in the thread are not discussing jitter.
It is impossible. In digital world if you have signal transfer problems they are not related to "more detail" etc. However jitter/jitter correction may change sound significantly. The first you should have only one clock source. You never should connect 2 devices each working on its internal clock.
I advise to read "The technical stuff" at Universal Audio 2192 ADC/DAC (my all time favorite) manual, it could be helpful:
AudioAvarice
Super Member
Google says early CD players had errors in the 10-100 nanoseconds range, which makes more sense, because that's one of the reasons they continued to develop the technology.
Yes, I agree it doesn't make sense from a purely "technical perspective" either. In practice it is observed, but not in theory. I'm not the only one who has encountered this personal observation either.
Well, but you did not think why there is a difference? For example, in analog audio, if output and input impedance does not match, any cable change will change sound. One example - Marantz 17series Ken Ishivata signature series. When you connect CD17KI player to PM17KI amplifier with good cables and then change cables to Oehlbach XXL sound changes dramatically. With oehlbach is much detailed highs. But it simply wrong design, now widely adopted by so called "Hi End" manufacturers to sell their cables. In digital world you do not hear digital signal what is transferred. If cable match standard and your system too there will be no changes in sound, no matter ADAT, SPDIF or AES (except for long distances). Between digital signal and you is DAC and any DAC has its own sound signature. If you use the same DAC for ADAT and SPDIF, but sound changes, it simply means you have a problem somewhere in chain. It can be bad ADAT cable too of course. Jitter is audible (after signal conversion of course).
Not about cables, but one example. In mid 90s there was only Plextor drives with integrated jitter correction chip so it was possible to rip audio CDs without additional jitter correction. But there was a problem - they all was IDE drives and on PCs of that time very unstable. Not enough buffer and your expensive CDR recording was interrupted. But they still was ok for ripping with any software. There was good SCSI Panasonic CD drives but - without built in jitter correction on extraction. CDRwin software (the best in that time) with jitter correction option solved that problems.
So moral of the story - in digital world if signal is jittery of course there will be audible difference after conversion. And it can be less detailed, colorization etc. But not because of format but because of system problems, jitter and jitter correction quality.
It's an interesting phenomenon, one in which I hear consistently across multiple devices, cables and scenarios. My guess is there's more than meets the eye and more to it that we don't yet understand mentally but can hear audibly. I don't think simply reducing all digital transmission differences or anomalies to 'system problems' or 'jitter only' fully encapsulates it. I've never found all 'digital' to sound the same. Whether the same digital signal is carried through fiber or metal seems to cause this slight difference in sound -even when the digital signal of ones and zeros passed through is identical.
How you know they are identical? Did you measured? Or only changed cables? We are talking about digital signal transfer from source to DAC. Simply google and read articles, there are full of them.
Nevermind, this is pointless. Carry on and good luck to you. They sound different when everything else is the same except the digital connection cable type.
This is not test
Everything can not be the same because one is coaxial RCA i/o another TOSLINK (I believe you mean both S/PDIF optical and coaxial not S/PDIF and ADAT)