Bits is bits?

[fas42]

18 minutes ago, psjug said:

Really?  I don't know how you expect to enjoy or evaluate the system with a fixed volume unless you only want to play from one CD.  I think it would make a lot more sense and a lot less work to use a source with volume control (something you know to be good) and go straight into the power amp.  Then you could take stock of what you have with the amp and speakers.  But no, I don't think I will follow this further and to be honest I am sorry to have discussed it here where it seems off topic.

 

Actually, it works mighty well ... you set the volume so that the quietest recordings are of a decent level, satisfyingly loud enough - then, even the most intense, driving albums come across the way that was intended. You see, when the SQ of a rig is in the right place then you can enjoy it at any volume - you never feel that "it's a bit loud - better turn it down!"

 

An audio friend in the area has got to the same place - one of the rigs which uses a recent Naim integrated has had the same resistor divider trick applied; the system was transparent enough to make it obvious that the pot was degrading the SQ.

 

Getting volume control to the right quality level is one of the major hurdles - well done digital level setting is the way to go; which is another of the key reasons that that first good setup I had decades ago snapped into shape.

[fas42]

33 minutes ago, STC said:

 

Finally, I see something. I can get those two wires and now I need to see the inside postures to see where you tap them. 

 

Dear me ... there's no mystery there - simply soldered to the circuit board traces adjacent to where the external connectors are attached to that board. I'm not fussy as to a precise, to the millimetre, point where they "tap in" - the point of the exercise is to bypass the electrical flimsiness of the box's connection hardware, no more than that.

[STC]

@sandyk did PM some files to me before. In one of them, I did (subjectively) perceived one picture to be different.  I didn't notice any difference with the other pictures. Unfortunately, I couldn't proceed with the tests vigorously because it was hard to look for difference with the iPhone XS. That was the only device I have that is up to 4K. Honestly, I didn't hear any difference with the audio files but that was due to my fault. According to Alex, JRiver wasn't recommended to conduct the comparisons.

 

It can be frustrating to Alex when there is something which he believes could make changes but he wasn't given a fair chance to prove his point. It is also frustrating to me (and probably to others) because the method Alex his advocating to hear the difference requires a set of equipment that is beyond my reach. 

 

Maybe Alex could use some royalty free music and make them freely available so that more people could hear and decide on the merits of his claim. Just my $0.02.  

[Hugo9000]

We are responsible for our own violation of confidences.  To blame others for our own posting behavior and attacks is ludicrous.

 

A certain member consistently attacks broad classes of people and professions.

He/she consistently attacks specific members.

 

These attacks may sometimes go unnoticed by general site membership due to thread cleanup that hides some very egregious behavior (not saying that was the intent of the site or thread moderator, but it's at least a side effect that affects perception if no one sees these horrible attacks before they are removed, and it allows people to overlook behavior that perhaps they wouldn't otherwise).

 

He/she repeatedly talks about how nasty others are, yet never acknowledges his/her own posting history of sharing personal and private information, illegal sharing of copyrighted material (sharing it in a PM or email is illegal, it just allows public deniability), etc.

 

When someone disagrees with this member, even in the most polite terms, he/she uses private correspondence in what appears to be an effort to shame others into silence or into public agreement, or to try to reduce their credibility in the eyes of others.  If someone says they no longer agree or feel they were in error, or they say they believe you took their statement out of context or read more into it than they meant, then please be respectful and let it go, not post a hundred times about how you have PMs from the past where this person once agreed.

 

Just because someone might appear to be rude to this member doesn't excuse the above behavior that he/she consistently engages in.  Perhaps someone was outright nasty to him/her ten years ago on another forum.  No one here needs to hear about it.  If it's being done here and now, other members will see it and can judge for themselves.

 

I assume I am opening myself to attacks now, or accusations that I am part of a (insert derogatory term for a profession or class of people) cabal, or accusations that I idolize this or that person.  I'm not a member of any clique.  If I "upvote" a post, it's because I think it's a valid point for me to consider in the thread topic, if I "like" the post, then I might agree with it, if I use "thanks" then it might be something I hadn't thought of or it was unknown to me and it's now valuable to me, or it might be "thanks" for saying something that I didn't have the courage to post myself, or that someone said better than I could have, or it's like "you're welcome" if it's in response to a post thanking me for sharing something.  I use "off topic" if I think it's off topic, not because I disagree, and I use "disagree" if I disagree with the post content.  I generally don't bother commenting or reacting at all if I simply don't like or respect the poster.  I am a subjective when it comes to my music, but I try to have some objective information when making decisions on purchasing or setting up gear.  There is so much equipment out there, and so much disinformation/FUD, that I need something to assist me in whittling down what gear to look at and what to listen for.  Measurements can be a valuable tool--I personally don't understand why anyone wouldn't want as much information as possible, while I am not able to make those measurements myself.  I own an old Fluke 16 and a Fieldpiece clamp meter from the same era, other than that, I own no test gear of any kind.  I do have 3000+ music CDs/SACDs, and I listen at least three hours per day, with my full attention on the music.  My only "idols" in life are a few musical ones:  a tiny number of composers, singers, instrumentalists.  So I hope no one will accuse me of being in one of these little feuding groups, that may or may not even exist here, but are used as distractions in the negative posting of some members.

 

I hesitate to post this, but perhaps there is someone else who, like me, would normally keep silent or just vent privately, so perhaps this is slightly useful for this point of view to be expressed.  I suppose some will call this post an attack, and hypocritical, and perhaps the worst offenders won't see themselves in any of this, but rather will see their own "enemies."  I suppose some will think this is just civility policing, although I think the types of behavior I criticized above are actually far worse than someone lashing out in brief anger with an expletive that might result in an automatic ban.  Sigh.

 

Back to music, and on topic, it is on digital media (CD), and I believe that it's a case of "bits is bits."  But perhaps I lack the expertise.  It sounds glorious, however, even though Neil Young's new book would say it's only 25% of the information that could be on a vinyl LP (which his graphic shows as "Hi-Res Analog" and is rated at 100% of the data in the recording).  lol  The recording is Verdi's La forza del destino, sung by Leontyne Price.  When I play my ripped files via my USB cable to an outboard DAC, it sounds identical to my ears to the CD playback.  I also have the LP set, incidentally, and it is clear to my ears and brain that the CD and the digital rip are superior in resolution to the LP hahaha!  But then, I guess my LP rig was always crap.  lol

[jabbr]

8 hours ago, Teresa said:

 

Alex, I'm a subjectivist and as a subjectivist I only believe what I experience with my senses, thus the results of these DBTs you keep posting over and over mean nothing to me.

 

If bit identical files sound different:

• Could it be the timing of the bits are different?
• Could it be system noise has somehow gotten in one of the files during or after digital to analog conversion?
• Could it be MD5 checksums are not accurate enough? 

 

Teresa, these are good possibilities, and on-topic for the OP.

 

1) Could it be the timing of the bits be different?

2) Could it be system noise ...?

 

These are two heads of the same coin. Noise can be voltage (or current) and noise could be phase (or timing).

 

Unless @alfe corrects me, it certainly is possible that two copies of a CD might sound different because of embedded noise on the media. It is also possible that two files on a hard drive might sound different.

 

This doesn't mean that the noise on an individual copy of the file somehow becomes embedded when the file is copied. Some people have tried to suggest, via ill-described and contrived  mechanisms, that such embedded noise might make its way onto new copies of the file, or across a network etc. It is this latter suggestion which not only does not conform to my own subjective experience, nor conforms to what we understand of electronics in great detail, and its this latter claim which has never been demonstrated in a convincing way.

[lucretius]

11 hours ago, Teresa said:

In my opinion bits are bits in the digital realm but when transformed into analog they become music. Music is what it is all about for me.

 

Actually, it's not music (or noise) until it comes out of the speakers. ☺️

[Ralf11]

I suspect many 'problems' with DACs are right after the bits are decoded to analog - at very low signal levels.

[marce]

I agree, how the analogue signals are treated before an ADC or after a DAC is critical, to any analogue/digital-digital/analogue conversion, isolation from the digital signals and return currents, separate power supplies etc. Lots of app. notes, data sheets and information from the likes of TI, Linear etc. Analogue layout is critical, all the parasitic's from the interconnection are extra components in the analogue chain so all has to be considered.

Bits are far easier to transport round a system...

[sandyk]

1 hour ago, marce said:

how the analogue signals are treated before an ADC or after a DAC is critical, to any analogue/digital-digital/analogue conversion, isolation from the digital signals and return currents, separate power supplies etc. Lots of app. notes, data sheets and information from the likes of TI, Linear etc. Analogue layout is critical, all the parasitic's from the interconnection are extra components in the analogue chain so all has to be considered.

. Most experienced DIY people are well aware of this. My own version of this Silicon Chip DAC uses separate transformers and PSU PCBs for both analogue and digital etc. as well as additional low noise regulation for both areas.

[marce]

I was referring to the layout of a specific DAC (or ADC) PCB...

[sandyk]

9 hours ago, marce said:

I was referring to the layout of a specific DAC (or ADC) PCB...

 

 The same principle applies.

[marce]

Yes. What Ralf was on about at the board level of the DAC, where analogue and digital exist in very close proximity, get it wrong here and all bets are off.

[Ralf11]

Yes, it is the same principle, but for a user or owner the difference is that they can change some things, but altering traces on a pcb is unlikely.  And very unlikely if SMDs/multi-level boards are used.

[sandyk]

6 hours ago, Ralf11 said:

Yes, it is the same principle, but for a user or owner the difference is that they can change some things, but altering traces on a pcb is unlikely.  And very unlikely if SMDs/multi-level boards are used.

 Not all DACs use a single PCB for both the main analogue and digital areas as can be seen in the photo of the original Silicon Chip magazine design that I posted a photo of.

[marce]

The DAC has to be an analogue/digital layout, sometimes having connectivity between boards especially ribbon cable connections can be more problematic than stuff on the same board.

[Confused]

Now this thread has calmed down a bit (unintentional pun), I would like to attempt nudge things back onto the "bits is bits" topic with a couple of bit related questions.  The first is eye patterns.  There are a number of devices that you can buy that claim to improve the eye pattern, and indeed this aspect is measurable.  But does it help sound quality?  This question has been asked before, and answered, two examples as follows:

 

"The spec allows for a 15% deviation, and cables might also vary in DC resistance. The important thing is that with a conforming source and cable, the eye pattern at the receiver will be within the defined limits, thus allowing correct recovery of the transmitted data. It is perhaps conceivable that a (poorly designed) DAC might be affected by noise carried, one way or another, over the USB cable and that differences in shielding or whatever between cable models might influence this. Even then, however, the descriptions of the effects (radically altered frequency response, etc) are entirely unreasonable. This suggests, to me, that the reported experiences are more likely imagined than the result of any real electrical differences." 

 

Thanks to @mansr for the above quote.  So to summarise, if you have a reasonably well designed DAC and the eye pattern is within defined limits, the DAC will recover the bits faithfully and all is good.  Not too much to worry about here.

 

On the other hand, we have threads like this that state that the eye pattern is very important indeed:

 

 "Without getting into the complexities of how to read an eye-pattern diagram or what it all means (such will get carried to another thread), I'll just say that an eye-pattern test is really the best all-in-one representation of signal integrity as it reveals variations in noise, amplitude, timing, jitter, edge-rates, etc. "

 

 

So, are the manufactures making this stuff up to promote their widgets?  Or is it a case that that at the margins, improving the eye pattern beyond the specification defined limits where correct recovery of the data can occur, will actually produce an audible or measurable difference to sound quality?

 

This is a genuine question by the way.  I know there are plenty of subjective reports to suggest that improving the eye pattern improves sound quality.  But is there objective evidence for this, anything that can be measured?  I am assuming here that for anyone where this kind of stuff might be of interest, they will already have a reasonably well designed DAC.  If not, this is probably the last of their audio related worries.

[jabbr]

The answer is: yes!

 

😂 yes the eye-pattern is the easiest best way to get a handle on signal integrity. In the vast majority of cases audiophile products do not provide nor likely measure eye-patterns.

 

One of the prime reasons I’ve selected 10Gbe Ethernet (even when run at 1Gbe) is that the standard mandates hitting an eye pattern for conformance. That’s to say you get great SI out of the box with conformant equipment (and these switches are available for much less than pennies on the dollar on eBay).

 

Similarly standard Ethernet cables made from Belden are SOA. These are used in eye pattern testing.

 

There is no evidence that any so-called audiophile Ethernet cable’s are in any way better or even equal to Belden (indeed they might be Belden with a fancy wrapper). 

 

USB I will leave alone. 

 

So could a DAC have SQ problems with an imperfect SI? It’s possible but hasn’t been demonstrated. 

[sandyk]

6 hours ago, jabbr said:

In the vast majority of cases audiophile products do not provide nor likely measure eye-patterns.

 

 In the vast majority of cases,  audiophile products use transports made by a small number of other manufacturers.

[fas42]

Worrying about the qualities of the eye pattern is just another way of allowing yourself to get bogged, deeply, in some technical side road - which is part of the bigger picture, yes, of everything that counts towards making sure the system is working right; but may simply be a great time waster, if the real goal is optimal SQ.

 

My POV is that I couldn't care less what the eye pattern looked like - I have absolutely no way of translating what it shows into something meaningful as far as what I'm hearing - therefore, ignore it. The real issues are in the receiving circuitry and DAC - my goal would be make that area fully robust, so that no matter how crappy the waveforms were being fed into it, the SQ altered not one iota.

[sandyk]

12 minutes ago, fas42 said:

- my goal would be make that area fully robust, so that no matter how crappy the waveforms were being fed into it, the SQ altered not one iota.

I don't know about these days, but the fact that simply using a green pen around the circumference of a CD resulted in audible differences, speaks volumes about the fragility of this area.

I wonder if more recent Optical blocks are unaffected by doing this ?

[fas42]

20 minutes ago, sandyk said:

I don't know about these days, but the fact that simply using a green pen around the circumference of a CD resulted in audible differences, speaks volumes about the fragility of this area.

I wonder if more recent Optical blocks are unaffected by doing this ?

 

I would just test it - by listening. The goal is to make it so that everything you can do to make it 'harder' for the end circuitry to always work correctly, by deliberately degrading the path in ways that could occur just as a normal part of everyday goings on, doesn't cause audible issues.

 

The principle is the same as that used for making sure that a bridge doesn't fall down - engineer it so it's 10 x as strong as it needs to be; then test it by loading it with massive weight way beyond any possible real scenario - then you have a very high level of confidence in its integrity.

[Ralf11]

the fact that simply using a green pen around the circumference of a CD resulted in confirmation bias, speaks volumes about the fragility of these minds

[sandyk]

2 minutes ago, Ralf11 said:

the fact that simply using a green pen around the circumference of a CD resulted in confirmation bias, speaks volumes about the fragility of these minds

 

 

No, it speaks volumes about YOU !!!

[fas42]

People listen in different types of ways ... once one has become sensitised to the type of distortion where all these sorts of "weird" factors tend to cause most damage, then it becomes trivially easy to pick something going on. The one that I started working with, and which is the easiest to pick, is the shimmer from a heavy cymbals workout, particularly in something like a rock recording - depending upon where the rig is at, this will vary from a barely audible white noise, something or other, carrying on in the background, right through to a fully recognisable and true to life sound of that instrument.

 

If someone doesn't know how to use recordings, properly, to assess the status of the playback quality - then they will always be struggling to evaluate how well it's doing ...

 

 

[Ralf11]

the fact that the most anti-audiophile poster on here believes that simply using a green pen around the circumference of a CD results in higher SQ, speaks volumes about the fragility of these minds