Coaxial vs Optical output?

[Deleted member 2191]

I’m completely inexperienced as far as the technology and measurements are concerned, so it will all be purely based subjectively as which sounds better to me

Forget about technology and choose what you like best.
It may not always be the same from album to album

 

[Yanto]

Forget about technology and choose what you like best.
It may not always be the same from album to album

Agreed. Good thing is it’s so easy and quick to compare

 

[onlyoneme]

However, it is necessary to disassemble it to understand the clock oscillator model used and connect to the TP1 ( I guess that's it) to evaluate the phase noise.
The photographs on the net do not allow you to read the oscillator model, at least not the ones I found.

https://device.report/m/735f54e7540ce5c6184839d271ddf70688b8bba9f72ac2c230b6f0c9f475b204.pdf

It's detailed not enough?

 

[Deleted member 2191]

https://device.report/m/735f54e7540ce5c6184839d271ddf70688b8bba9f72ac2c230b6f0c9f475b204.pdf

It's detailed not enough?

Much better than the low resolution ones I had found, but they are not enough.
To disassemble the Pro all you need is a screwdriver and a few minutes, so you might as well do it.
Thanks anyway.

 

[onlyoneme]

Much better than the low resolution ones I had found, but they are not enough.
To disassemble the Pro all you need is a screwdriver and a few minutes, so you might as well do it.
Thanks anyway.

Sure, just 4 screws under the rubber if I remember correctly.

 

[Balthazar B]

Coaxial vs Optical output? Which has a better sound quality?

For most people, there won't be any audible differences. Optical has a possibility of jitter, while coax (with a truly crappy cable) could have audible defects. But most people will probably not experience these.

Now there have been a few scattered reports that mechanically, WiiM's optical hardware can be prone to failure, so that could be a consideration if you'll be detaching the Toslink cable from time to time. If something breaks, then you *would* hear a difference (mostly because you won't be hearing anything at all from the optical connection).

OTOH, there have been complaints that the recessed coax jack is too narrow to fit some (generally high-end) coax cables. But I haven't seen any reports of the jacks going bad mechanically, so there's that.

 

[Wiimer]

Coaxial vs Optical output? Which has a better sound quality?

I don't know if you can feel the difference in sound quality, but we recommend using coaxial output for safety and stability.

The optical output of the WiiM may generate noise at 24/192kHz. For example, there have been reported issues connecting to IFI Zen One.

Also, one of several DACs I own makes noise between tracks (SMSL M200) . This happens between tracks with different sample rates. This can almost be resolved by adjusting latency, but it is an open issue.

 

[onlyoneme]

Jitter is a time deviation of any type and origin. It can be random or deterministic, unpredictable or predictable, but it's still a jitter.
Both cables will transmit a jitter injected by the source. And both can be affected by a transmission medium induced jitter, as shown on the eye pattern for example.

 

[Deleted member 2191]

Jitter is a time deviation of any type and origin. It can be random or deterministic, unpredictable or predictable, but it's still a jitter.
Both cables will transmit a jitter injected by the source. And both can be affected by a transmission medium induced jitter, as shown on the eye pattern for example.

The jitter is a variation over the time, not a simple variation.
If the variation is constant the jitter is zero.
In this case we have to talk about delay and not about jitter, which however, not including a variation over time, is not perceptible.

In the event that the variation was foreseeable, it would be entirely compensated, and consequently it should equally be considered null.
Consequently, the term jitter indicates a variation of an unpredictable quantity over time.

 

[onlyoneme]

The jitter is a variation over the time, not a simple variation.
If the variation is constant the jitter is zero.
In this case we have to talk about delay and not about jitter, which however, not including a variation over time, is not perceptible.

Of course it's a variation over the time, it was not about a constant clock drift or delay. But it can be still deterministic and predictable, not only random as you've written in the deleted comment.
Just look for "random jitter" and "deterministic jitter" terms.

 

[Deleted member 2191]

Of course it's a variation over the time, it was not about a constant clock drift or delay. But it can be still deterministic and predictable, not only random as you've written in the deleted comment.
Just look for "random jitter" and "deterministic jitter" terms.

There is a notable difference between a "variation" and a "variation over time": the first cannot be perceived as being constant it produces no effect, the latter can be perceived.
That said, the term jitter is usually used to indicate an effect that cannot be compensated (otherwise it would not be part of the noise family), which excludes predictable variations.

 

[Deleted member 2191]

A clarification: the transmission medium itself can hardly introduce jitter, unless there are variations of a parameter involved in the transport of the information (for example relative motion between source and destination).
However, this does not mean that a coaxial cable or an optical fiber cannot introduce jitter, because the electronic devices involved in transmission and reception can cause jitter.
The main cause is the phase noise of the clock they are locked to. Phase noise is public enemy #1 in all of precision electronics, and sadly it's also the least known characteristic, to the extent that manufacturers rarely claim the phase noise characteristic of the clocks they use in their equipment.

 

[onlyoneme]

I do not know what you are referring to atm. In the deleted comment you've suggested that coax cables do not induce a medium related jitter, which is not true.
Jitter is about timing deviations, variations over the time, being considered as random or as deterministic. AFAIK there are known ways to suppress both kinds of jitter although the first one cannot be fully compensated due to it's random nature, as you've stated already.

 

[Deleted member 2191]

I deleted it because I like to be precise in definitions and what I said, to be accurate, would have to include an extension that is out of place in this forum.
But if you really care... can a constant transmission medium introduce jitter? well, before Mr. Plank we would have said no, it can't do that.
We've known since 1920 that it can.
Referring to the coaxial cable or optical fiber that connect two HiFi components, what temporal indeterminacy can we expect? I would say something a little less than 1 pS, ie a temporal indeterminacy of a thousandth of a thousandth of a millionth of a second.
Now, imagining being able to assimilate such a temporal uncertainty to zero, what was said in my previous post remains valid: jitter can exist, but it is not attributable to the transmission medium but to the ebtpoint clock. Which, however, concerns coaxial cables and optical fibers in the same way.

As far as jitter is concerned, if you simply say "jitter" you are referring to the "total jitter", which is the sum of predictable and random jitter.
The predictable jitter exists only as part of an equation, it is not a real quantity, the real jitter is the total jitter.
You can't take an instrument and measure predictable jitter, because your measurement will always be about total jitter.
Having an unpredictable part, it is always unpredictable.

 

[onlyoneme]

I do not recognize any jitter measurements for different transmission media, so no idea what values to expect for medium induced jitter.

When I think about a measured jitter I see the total jitter here, which contains its random part, yes. However when talking about a phenomenon called jitter, it belongs to its own category, thus it's going to be random or deterministic even if not explicitly defined. Having a jitter measured as a total jitter usually does not mean that jitter itself must be random.

 

[Deleted member 2191]

Conversely, measured jitter is always a conjugate quantity.
At most you can apply an inverse transfer function to zero the predictable component, and in this case the measurement would return the random part.
There is no way to zero out the effects of the random part to measure the predictable part, if that were possible we would be violating the uncertainty principle.
Quite a complicated thing to do.

 

[Deleted member 2191]

However I think quantum mechanics and the uncertainty principle are a bit beyond the scope of this forum.
Which is the reason I had deleted that post.

 

[Brantome]

However I think quantum mechanics and the uncertainty principle are a bit beyond the scope of this forum.
Which is the reason I had deleted that post.

The uncertainty principle? Are you sure?

 

[onlyoneme]

The uncertainty principle? Are you sure?

You've never met Herr Heisenberg? Shame on you

 

[Brantome]

You've never met Herr Heisenberg? Shame on you

I’ve only seen him on Breaking Bad