Do I need clean USB power when using DAC with its own power supply?

[fas42]

39 minutes ago, Archimago said:

 

Bottom line is that I see a lot of words by people who complain about noise, yet in all these years, where's the evidence? For those who have "issues" with switch mode power supplies, what exactly are you hearing? Is this something you've measured?

 

 

 

What one hears is a degradation of SQ - it's almost never an actual 'noise', which is audible over the speakers; or prominently visible on a scope, say.

 

A simple test: a recording which is marginal to listen to - that is, at times it can sound awful; or, other times it's quite pleasant to experience, nothing untoward that stops one from enjoying the performance ... a noise interference issue can well and truly send the listening right down the negative end - you are ready to hit the stop button almost immediately ... that's the nature of the beast.

[fas42]

44 minutes ago, kumakuma said:

 

I have never had this experience. I wonder if anyone other than Frank has.

 

In fact, I'm curious what people's experiences are, in general ... I doubt I am the only person who has heard a particular recording sound pleasant on one rig, and quite unpleasant on another - if both setups are supposedly somewhat "accurate", why is this?

 

Troubleshooting system issues is all about reacting to this variance - for years, the now and again visits to the local audio friend have been sessions of tracking what ails the setup, at the time ... strangely, people with TTs have known that SQ changes with adjusting things - but, ahh, that's mechanical; in the magic land of electronics, the special qualities of such items guarantees uniformity of behaviour, no matter what ... 🙃.

[fas42]

17 hours ago, kumakuma said:

 

Is that what you meant?

 

It sounded like you were talking about the same recording on the same "rig" sometimes sounding good and sometimes sounding bad.

 

The same system can sound different, just as much as different rigs typically sound different from each other - understanding why it occurs for a single setup, where none of the basics are altered, is how to improve understanding of what matters.

 

16 hours ago, Archimago said:

 

Unless you test this somehow, how do you know if the "supposed" accuracy is indeed the case?

 

Trouble is, accuracy is a complex thing, when talking of the hearing sense - the normal objective stuff is trivially easy, if you have the right measuring gear; but most agree it gives little idea of what it's like to live with ...

 

16 hours ago, Archimago said:

Besides, when it comes to "setups", usually we're dealing with variations in speakers, rooms, maybe amps. Much less likely that small fluctuations in the USB DAC (noise or other distortion) are the main issues.

 

No. The closer the system is to achieving high transparency to the recording, the less important are speakers, room, etc; and the more important is the absence of noise and similar issues - the crossover to convincing illusion status only occurs when the latter is sufficiently sorted.

[fas42]

23 minutes ago, hopkins said:

In digital audio, things are very simple: either a recording is accurately reproduced by a DAC or it isn't. If it is, then everything else,  including PRaT, soundstage, ect.. follows. 

 

 

Except, I would replace the word "DAC" with "system" - most setups fail to live to expectations because the overall chain is not accurate; for example, the DAC may be "perfect" in isolation, but its power supply current draw waveform is enough to disturb the accuracy of the amplifier - it is never enough to isolate the performance of a single component as being key; it's always going to be how well the combination of all parts functions.

[fas42]

1 minute ago, kumakuma said:

 

Never had this problem and the flawed recordings that I own sound equally flawed on every system I've every heard them on.

 

Since day one, over 35 years ago, of having capable playback I have had the problem of recordings sounding acceptable, or unacceptable, depending upon the 'tune' of the system ... people listen to playback with different mindsets; unless one is in the same room with the other person, hearing what's going on, then communication on the matter is always going to be difficult.

 

As an example of a recording that was very much on the edge, I have a standard CD version of Carole King's Tapestry - I played that album of the order of a 100 times back then; because it immediately told me the status - when below par, it set my teeth on edge; it was, unpleasant. By contrast, current actives sail through this very same recording with ease ...

[fas42]

7 minutes ago, March Audio said:

Prat is just a made up term, it has no meaning.  

 

Just ask people to explain it and see how far you get.  If you take the actual meaning of the words then it makes little sense.

 

If you are concerned about pace, rhythm and timing, don't ever play an LP record with its inherent speed fluctuations which are massive compared to digital audio.

 

Lack of PRaT is very much a subjective sense of the music - it's comparable to an orchestra playing with no conviction, in a practice session, causing the conductor to start yelling at the musicians, wanting to kick their backsides - he knows the PRaT is bad; and has to shake them up, to lift the mood.

[fas42]

1 minute ago, kumakuma said:

 

Perhaps it's a wetware problem...

 

Which is why I said,

 

Quote

... people listen to playback with different mindsets; unless one is in the same room with the other person, hearing what's going on, then communication on the matter is always going to be difficult.

 

[fas42]

Just now, March Audio said:

I had to answer this even though I'm trying not to feed Frank.

 

How can you possibly compare a conductors function to that of a playback system?

 

All the things the conductor controls in an orchestra are fixed permanently in the recording.

 

Pace rhythm and timing are exceptionally tightly controlled in a digital system.

 

 

 

I'm talking of the subjective impression of the music one's hearing; not why it sounds like that - the conductor conveys a sense of urgency to his players, and they respond. Yes, the recorded performance of that is now permanent, but I most certainly have heard playback of some track where the sense of it is indeed that the musicians are "dragging their feet" - since I have heard the very same track full of life and vigor on other occasions, the fault must therefore lie with some aspect of the playback SQ.

[fas42]

45 minutes ago, March Audio said:

No Frank, the difference is in your head.  That's not meant to be rude BTW.  You just really need to recognise that your (mine) perception is not a constant.

 

If you did you might stop chasing your tail with all your pointless tweaks.

 

Alan, it's obvious that you need to live in a world where everything is neatly explained; especially when one can extract a neat set of numbers, and graphs, that tidy it all up. Unfortunately, reality conspires against us, all - and it has been thus since mankind first threw a bone or two in the air, 😄.

 

You just can't keep pushing everything uncomfortable away, and sweeping it under the "it's all in your head!" carpet ... extracting optimum audio playback is still very messy; that's the nature of the beast, to this day - tweaking is one of the best workarounds, until the whole industry develops a better understanding of how to control all the important factors.

[fas42]

Interestingly, one of the very few systems that stood out as "getting the sound right" at the last hifi show I went to used a CH Precision CD player ... 😉.

 

The discussion here is like the situation where the owner of a new car enters a battle with the servicing department of the dealership: "There's a problem with my car; it doesn't drive properly!" ... "Well, we've checked everything, taken it for drives - and it seems fine to us". Either the owner gets fed up, and ditches the vehicle, as soon as he can - or if he's lucky, enough people experience similar issues, and the combined weight of their protesting finally pushes the manufacturer over into admitting that there's a problem. In audio, this never really happens - and so the irritating lack of proper resolution of deficiencies, etc, just continues.

[fas42]

One only has to go to a hifi show to see and hear how immature the industry still is - room after room of laughable, or downright awful sound, making a complete mess of the recording. If the 'objective' POV was so capable, so on top of everything, then it would dominate the situation - easily able to provide stunning reproduction, which would make it obvious that all other approaches were deficient - and hence they would disappear.

 

The disappointment that the industry is still so hopelessly slow at evolving to a point where a system can just be put together, and work - meaning that it replays recordings to a competent standard with no fiddling necessary - is what keeps me involved in forums like this ... yes, there are some bright spots, now - but, Jeeez, it's gonna take forever to get there ...

[fas42]

It is the subjective that counts - just now was running some tracks of a 70's band playing 50's music, the Aussie Daddy Cool group - this was able to project the intensity and bite of a live rock and roll band happening, only feet away from one - but how does one measure this highly subjective "vibe", currently?

[fas42]

28 minutes ago, BassFace said:

I can highly recommend reading and watching Rob Watt's from Chord Electronics talk about this in his DAC design. He goes into how a change in sound to you doesnt mean its better.  Infact he proves how people are actually wrong when they think a DAc sounds brighter, clearer etc when it actually doesnt. 

 

 

Link?

[fas42]

37 minutes ago, BassFace said:

Google is your Friend 👍

 

All right, I've got Google here ... what do I feed it, to find " Infact he proves how people are actually wrong when they think a DAc sounds brighter, clearer etc when it actually doesnt"?

[fas42]

1 hour ago, BassFace said:

Im not your personal secretary but Im sure if you were to look properly instead of a smarty pant reply you'll find it in no time 👍

 

Thank you for being helpful ...

[fas42]

1 hour ago, hopkins said:

Perhaps some of us are more or less sensitive to particular aspects of sound reproduction, whatever the reason may be? (I'm not saying "audiophiles" have special hearing abilities). What is important to one person may be irrelevant to another.

 

Are these "subtleties" essential? When I'm listening to music on my phone with my 20$ Porta Pro headphones I cannot hear them, but I still enjoy what I'm listening to! But sometimes I tell myself: I can't wait to listen to this track on my speakers 🙂

 

We also have to acknowledge that our hearing is still an ongoing topic in scientific research. What makes it so sensitive (probably more so than audition tests may reveal)? Here's one interesting read:

https://news.mit.edu/2007/hearing-1010

 

Anyone who has little trouble distinguishing a situation of conventional quality audio playback from the "real thing" will appreciate what a competent system brings to the table - the fact that the latter is still far too rare is a sad indicator of the state of the industry; largely caused by the lack of decent research into the sensitivity of the ear/brain to disturbing anomalies. And has led to the appalling SQ of most sound reinforcement setups - people are so used to the terribleness of the general standard that they actually expect that this is "how it should sound!" ... help !!!

[fas42]

3 hours ago, hopkins said:

 

Absolutely. I have found that there is a lot of reticence from some audiophiles to participate in blind tests as they are convinced they are "objective". My suspicion, however, is that some are simply worried about the outcome. They see it as a stressful situation where they may end up "losing" (what?).

 

 

The confounders are a big problem in any of these sorts of things in audio - you're supposed to be assessing the value of some variable; but another non-varying characteristic is screaming at you - and "masks" what which you are meant to be influenced by.

 

An obvious one for me: with and without 'perfect' FR correction using a DEQX unit - the other, obvious flaws of the playback rig were shouting at me; and completely dominated the experience. As some say 😁, pick the low hanging fruit first; then worry about the stuff at the top of the tree later ...

[fas42]

The pro market is certainly different ... some years ago I did an exercise of spending the day going to every pro shop in Sydney, and listening to every model that people would call near field units - irrespective of cost. They were almost universally awful, and tended to fall apart as soon as some volume was called for - umm, any engineering done on these, boys ... ? 😉

 

The best performer on the day were almost the cheapest, a Behringer model - it actually had a good measure of clarity and detail in the sound; something most of the others could only dream of 🙂 .. so I bought them ...

[fas42]

1 hour ago, BassFace said:

Have you ever listened to some Ex Machina? Genelic 1238's?  Nuemann KH420?  PMC BB6S XBD-A?   Strauus Elektroakustik?  Adam S5V? ATC SCM models?  All used regularly and highly respected.   Slightly better than the Behringers and Classic Bedroom KRK Rokits that I think and suspect your confusing for Pro one might say.

 

I'm sure that there are models, especially now,  that would do better, much better, than what I heard on that day - interestingly, a pretty expensive Mackie - not sure the model now - blew one channel while we were auditioning - not very reassuring, 🙂. I was curious whether the actives of the day would show up conventional hifi stuff, as many suggest - but it appears that one has to venture into the pricey gear to obtain credible results.

[fas42]

15 hours ago, BassFace said:

Mackies are not considered decent just to inform you. Cheap Party/PA's at best  same with their bargain basement (i use the term loosely) montiors.   My point still stands, they are not good equipment.  Cheap Budget at best. So how on earth you can draw any kind of reference or opinion from that baffles me.  Like I said, from what youve said all youve ever tried is cheap commercially available bedroom stuff.   

 

I note amongst other things your apparent inability to read ... I specifically stated

 

Quote

... every model that people would call near field units

 

and every model I checked, that you mentioned, is at least a mid field unit - that is, specifically designed to have plenty of grunt.

 

Edit: Posted this before noting following comments ...

[fas42]

Duuh post ..

[fas42]

Note that the original post I made started with the point I was making, that is,

 

Quote

The pro market is certainly different .

 

That's the thing I was focused on - and I disturbed some people by finding that one of the cheapest items I looked at was, subjectively, quite a bit better than the others, on the day. I have had trouble with people being upset that I don't equate cost to specialness, ever since I started posting on forums - but that's an angle I'm not interested in...

[fas42]

4 hours ago, hopkins said:

To get back to the topic of USB, noise, and measurements... 

I would be curious to know:

 

- whether people who buy these new "budget" DACs purely based on specs and measurements end up keeping them very long ? Looking at ASR, it seems that forum members are in a permanent state of excitement about the newest models - while the previous models measured just as well or the differences were supposed to be inaudible!

 

 

There is a large grouping of audiophiles who are into the excitement of constantly upgrading their gear - that's a pleasure in its own right, and if they have the means to indulge... why not? 😉

 

As most in the audio world know, conventional measuring is quite hopeless at assessing whether an audio chain is accurate; and is almost never used for evolving a setup to be accurate ... the fact that every rig sounds so different, often dramatically, from the next one is the obvious giveaway that accuracy is still a far away dream ...

 

Noise is a major part of the reason why - with quite obvious, highly audible consequences ... no work is being done to work out a strategy for measuring the impact of noise on an overall, assembled system - and the hopeless state of the industry, with 'snake oil' everywhere, tells the story.