Upgrade Power supply vs cable vs DAC

[Fourlegs]

I did not mean to imply characterisic impedance and that is not what I meant and I don't think it is what Rob Watts meant when he described it to me - assuming you are accusing me and Rob Watts of howling at the moon.

 

[Heckyman]

Interesting observations and thanks for taking the time to write them.

I've also experienced something similar (but different examples).

In the end though, it all depends on the system context. This can get incredibly complicated once you throw cables and power supply into the mix!

 

[rabski]

I did not mean to imply characterisic impedance and that is not what I meant and I don't think it is what Rob Watts meant when he described it to me - assuming you are accusing me and Rob Watts of howling at the moon.

No, but there are some comments along those lines. Also, there are a lot of 'may be due to', where there are already perfectly simple and far more likely explanations. I agree with the 'noise' being one, though as the general suggestion is that it comes from the source, then cable length is likely to be irrelevant. The impedance having an effect at RF would be the characteristic impedance, which, as above, is independent of the cable length. Effects from resistance and capacitance are a different issue, but trying to filter RF in this way would be nonsensical, as it would be frequency dependent.

 

[Fourlegs]

No, but there are some comments along those lines. Also, there are a lot of 'may be due to', where there are already perfectly simple and far more likely explanations. I agree with the 'noise' being one, though as the general suggestion it that it comes from the source, then cable length is likely to be irrelevant. The impedance having an effect at RF would be the characteristic impedance, which, as above, is independent of the cable length. Effects from resistance and capacitance are a different issue, but trying to filter RF in this way would be nonsensical, as it would be frequency dependent.

and of course when postulating what difference a digital cable might make to the signal that must also be accompanied with an explanation of how that might affect the sound. Most seem to think just mentioning jitter or some other word is enough in itself.

Many explanations of the process are similar to the South Park explanation as to how to make a profit out of stealing underpants, ie

Phase 1.  Steal underpants.

Phase 2.

Phase 3. Profit.

Our kids loved this show.

 

[rabski]

I don't subscribe to the idea that everyone with an interest in hifi is gullible and easy prey for advertising. On the other hand, I have to laugh at the amount of sheer bull droppings abundant, a lot of which revolves around the suggestion that cause automatically means effect. You can spend a lot of time and money eliminating something in the signal chain that is actually already rejected further down the line, or makes no difference anyway. Alternatively, in doing so you can easily ignore something that does have an (unexpected) effect.

 

[Blzebub]

There is sound science behind the suggestion to make digital coax cable a specific length. I need to look it up or work it out, but it relates to the wavelength and internal signal reflections cancelling or reinforcing.

"The wavelengths of radio waves range from thousands of metres to 30 cm."

https://www.britannica.com/science/radio-wave

If the max wavelength is 30 cm, surely any cable longer than that will not encourage reflections?

 

[Blzebub]

I posted a link earlier in the thread:

https://positive-feedback.com/Issue14/spdif.htm
 

I agree that it sounds logical but it is intriguing that no DAC or cable manufacturer, pro or foo, has picked up or made reference to it

I read the link (monograph). It reads like an opinion piece. No references to textbooks or research articles are given to back up what he's saying.

 

[rabski]

"The wavelengths of radio waves range from thousands of metres to 30 cm."

https://www.britannica.com/science/radio-wave

If the max wavelength is 30 cm, surely any cable longer than that will not encourage reflections?

Reflections within a cable will always occcur. The issue is when they can interract and result in reinforcement or cancellation. This is a perfectly well-known phenomenon in high-frequency work and is a major consideration in designing PCBs for higher frequencies.

The extent of any issue affecting digital transmission in 'our' applications is more likely to depend on the robustness of the signal and the ability of the receiver to reject unwanted signals. For the sake of 'it cannot do any harm', I prefer to keep SPDIF cables at multiples of 1.5m, but frankly it's almost certainly unnecessary.

 

[tuga]

and of course when postulating what difference a digital cable might make to the signal that must also be accompanied with an explanation of how that might affect the sound. Most seem to think just mentioning jitter or some other word is enough in itself.

I agree in principle.

With the caveat that there isn't a universal language for characterising sound and thus any description of potential audible attributes can go from explicit through confusing to meaningless depending on the adjectives and the receiving entityphile.

.

I would also add that in my view improvements in performance are always desirable even when not producing audible advantages, unlike many at ASR which believe in "adequate" or "good enough".

 

[tuga]

That article concludes by saying, "Once the impedance is accurately matched and the transition times decreased, the Transport will become less sensitive to different digital cables, shorter cables can be used with confidence and the result is cleaner audio with better focus, definition and clarity."

I have highlighted the last three words because in my experience the use of those descriptive words is usually a dead give away for the presence of RF noise induced artifacts giving an initial impression of 'better focus, definition and clarity' but which often becomes fatiguing with extended listening.

This, in bold, is what I was referring to in my previous post.

There's a huge chance that someone else may not use those descriptive words in the same manner, and thus the "presence of RF noise induced artifacts" is not a given/fact.

Higher fidelity / increased "transparency" / lower noise and distortions will, in my view and experience, produce "cleaner audio with better focus, definition and clarity".

.

Though I agree that artifacts may produce a perceived "better focus, definition and clarity". Depends on the listener.

Which is why I am dismissive of subjective reports most of the time...

 

[Fourlegs]

Reflections within a cable will always occcur. The issue is when they can interract and result in reinforcement or cancellation. This is a perfectly well-known phenomenon in high-frequency work and is a major consideration in designing PCBs for higher frequencies.

The extent of any issue affecting digital transmission in 'our' applications is more likely to depend on the robustness of the signal and the ability of the receiver to reject unwanted signals. For the sake of 'it cannot do any harm', I prefer to keep SPDIF cables at multiples of 1.5m, but frankly it's almost certainly unnecessary.

But until those musings are linked to either an observed change in sound quality or a proposal as to how they might affect sound quality then they are just musings with just as likely no impact on the the digital cables in our systems. 
 

The other way of looking at it is to consider just how bad a digital cable has to be before it impacts on the digital signal. I suspect the answer is it has to be very poor indeed to do that. More likely is a badly crimped connected on the plug that causes intermittent contact with clicks and other noises being the result but in between any clicks it probably sounds ok.  
 

The harmful noise I am discussing is generally mentioned as being in the 2 to 5 GHz area, ie well outside the music carrying digital signal. I have yet to see anything that concludes that any half decent digital cable cannot preserve the integrity of the digital signal for the 1m or 2m (or longer) length of cable in normal use.

 

[tuga]

But until those musings are linked to either an observed change in sound quality or a proposal as to how they might affect sound quality then they are just musings with just as likely no impact on the the digital cables in our systems. 
 

The other way of looking at it is to consider just how bad a digital cable has to be before it impacts on the digital signal. I suspect the answer is it has to be very poor indeed to do that. More likely is a badly crimped connected on the plug that causes intermittent contact with clicks and other noises being the result but in between any clicks it probably sounds ok.  
 

The harmful noise I am discussing is generally mentioned as being in the 2 to 5 GHz area, ie well outside the music carrying digital signal. I have yet to see anything that concludes that any half decent digital cable cannot preserve the integrity of the digital signal for the 1m or 2m (or longer) length of cable in normal use.

If it makes the receiver work harder tehn perhaps there is a chance that this will generate which noise may affect the D/A chip. :?

 

[DomT]

@tuga Ric I see that you seem to have an new avatar and the man seems to have an axe in his hand. Are you trying to tell us something?

 

[DomT]

Anyway with several more hours of listening this DAC2 is really fabukius sounding. Just a shame that one of my most favourite albums (Goldfrapps first one) is revealed to not having been mastered well and doesn’t sound great (a bit harsh) as does U2’s best of 1980-1990. Loads of albums that could really have sounded very bad are actually sounding very good. And some are really stunning by comparison with the DAC1. It helps that I am sitting nearfield 90cm from the speakers.

 

[Griff500]

I would also add that in my view improvements in performance are always desirable even when not producing audible advantages, unlike many at ASR which believe in "adequate" or "good enough".

:^

I have a feeling that the cumulative effect of these types of improvements can become audibly worthwhile even when they are individually inaudible. 

When I started upgrading my system last year I certainly didn't have the goal of ending up with an adequate system. ;-)  

 

[Griff500]

@tuga Ric I see that you seem to have an new avatar and the man seems to have an axe in his hand. Are you trying to tell us something?

I hadn't spotted that.  :rofl:  Well played @tuga  :rofl:

 

[DomT]

:^

I have a feeling that the cumulative effect of these types of improvements can become audibly worthwhile even when they are individually inaudible. 

When I started upgrading my system last year I certainly didn't have the goal of ending up with an adequate system. ;-)  

My studio room started out as an adequate Marantz PM7000N. Perfectly adequate for listening to music on. But then I found that adequate wasn’t enough. Hence what I have now. 

 

[tuga]

@tuga Ric I see that you seem to have an new avatar and the man seems to have an axe in his hand. Are you trying to tell us something?

Shhh... I'm a man with a mission. h34r:

 

[DomT]

Shhh... I'm a man with a mission. h34r:

Aaah you are undercover. Ok! Shhh!

 

[CnoEvil]

Shhh... I'm a man with a mission. h34r:

Mission Impossible!