Track preload affects sonics - HELP!!!

[fas42]

Can't help you with the computer (mis)behaviour, but certainly noted this factor with a CD player, very strongly, years ago. Currently still using CDs, but if it exists with the CDP being used I haven't got to a level of SQ yet where this may be an audible influence. A local audio friend who uses normal media players as source discovered that the precise sequence of accessing a track, and initiating play made a difference; worked out the best combinations of settings and actions, and now it's a standard ritual when listening.

 

Why does it happen? I suspect it varies per component, and it's all to do with some electrical, interference or processing activity that needs to stabilise over some period, or by performing a certain action. Can be very irritating to deal with, and once one is aware of the behaviour you can't forget that it's there!

 

What to do about it? With processor based playback I would experiment, experiment, experiment - until I found some combination of actions and settings that was least annoying, that I could live with. The real answer is that the engineering of the device needs to be improved so that this sort of nonsense doesn't happen - but with commodity items that's never going to happen, . In the long term, track down and move to another computer, etc, which doesn't show this trait - is perhaps the best strategy.

[fas42]

1 hour ago, Ishmael Slapowitz said:

".. is not subtle"..

 

this the go to remark from those who listen to micro details and not music. Just IMO of course. 😎

 

Unfortunately, it can be the difference between the music sounding a bit flat, tired, uninteresting - versus sparkling, lively, something that engages one emotionally. That is, subjectively, it matters a great deal - for some people.

[fas42]

2 hours ago, Ishmael Slapowitz said:

As psychiatrist,  this stuff plays in to the worst OCD tendencies. 

 

Show me the same results blind. How about captures off the DAC analog output Measurements? This sort of magical stuff

should be able to be measured.

 

Distortion is not magical. "Should be be able to be measured" is correct, but the industry hasn't taken the interest in devising useful tests - inertia is an effective tyrant.

 

In the meantime those who are interested use their ears - those who are not interested can be comforted by reassuring measurements of competence .

[fas42]

18 hours ago, Ishmael Slapowitz said:

I am not a measurements guy, trust me. But there is no distortion. 

 

The premise of this thread is silly, and lead many who should be enjoying good playback down the primrose path.

 

There is always distortion from playback systems, no matter how expensive or optimised they are - if there wasn't, a rig would always sound identical playing back a particular recording . Some distortion types are very easy to measure, others much less so - and I worry, a lot, about the latter varieties.

 

Unfortunately, the hard to measure versions have a lot to do with conveying the quality of vitality, and 'naturalness' in recordings - but very few people take these areas seriously, which is a shame.

 

Again, the real solution is to engineer the playback components to a much higher standard - but that's unlikely to occur in the short term ... workarounds, etc, are usually the best option, as it stands.

[fas42]

2 hours ago, Ishmael Slapowitz said:

I don't disagree with your post, Yes of course there is always some sort of distortion, heck there is distortion at the point of mic or DI capture. Just as there is bacteria in every morsel of food we eat. The question is does it matter.

 

Yes, I agree the heart of it is, does it matter? IME, it does. The types of distortion that particularly prevent the mind from perceiving a convincing illusion are the most critical to sort out - because the difference in the subjective sense of what one hears is quite dramatic. Unfortunately, it's a whole lot of little, insidious shortcomings, weaknesses in the system overall that do the damage - which can all be resolved if one takes the time to do so.

 

Audio playback can deliver the same oomph as live performance of music - but this is extremely rare, because very few people take the steps to 'debug' their rigs sufficiently.

[fas42]

2 hours ago, Paul R said:

In any case, from memory, I think that the effect is quite real and easily documented, but I think it has something to do with auditory memory not with playback performance.

 

The second time round, you already know what to expect and your attention is better focused, or something like that.  In any case, it would be interesting to see what real honest to John measurements say about it.

 

 

This may be relevant in some instances ... there are so many variables; one of the behaviours I've run into a far bit is that the sound will start off coming across well, and then steadily over some period, could be minutes, could be hours, will slowly degrade - one attempts to convince oneself that it's "all in the mind"; then you put on some album that screams at you, "this sounds awful!!".

 

What's happening is that various electrical factors are stabilising, or steadily shifting into a state where they cause the key circuitry to stop functioning as well as it should - it's not your imagination!! To solve the problem may require some detective work - but all these issues can be resolved .

[fas42]

4 hours ago, Paul R said:

 

I hate to say it Fas old man, but a cause for that which is much easer to understand is that every system has auditory flaws that cause listening fatigue - sooner or later. In general, the better the system, the longer one can listen without [damn typo! -> without <- ]  the onset of fatigue.  

 

Yes, that would be so in many cases. However, getting a rig up to the levels I'm interested in means the onset of fatigue never happens; we've had previous setups running from early in the morning until we go to bed, with the sound going throughout the house - not a problem.

 

4 hours ago, Paul R said:

 

It could be that sound is not really changing. Only hard and fast measurements will tell us which answer is the real reason. (Or point to another reason entirely.) 

 

Have you measured the output of a device and actually seen it change?  That would be very compelling evidence for what you believe.

 

-Paul 

 

 

I would have been tempted to investigate here, but for the fact that others who believe in the subjective approach, who also have access to plenty of precision measuring gear, have always stated that they are unable to find clear numbers that link to what they hear. Why should I think I can do better?

 

It's been trivial to always hear what's going on, for me. If sound seems wrong, then it is wrong - this attitude has worked for 3 decades; the goal has always been invisibility of the playback mechanism, ability to go to any sane volume with zero audible issues, zero disturbing anomalies in what one hears - I tend not to come across many systems with this attributes; so, not motivated in finding numbers for this at the moment ...

[fas42]

11 hours ago, Paul R said:

 

Well, subjectivist, objectivist, or just an independent cuss,  measurements are a tool that helps us understand what we hear, see, feel,  and believe. I certainly do not believe measurements are the beginning and end of the story, especially about audio.  I can't think of a good way of testing to validate this other than measurements though. 

 

Dennis, esldude, has provided us with some good data to play with, in the 8th copy threads. The final copy is obviously distorted, because one can hear the difference. So, work out how to measure what has happened to the degraded sample, in the areas where one can clearly hear the variation - if one can correlate a measurable difference to the audible symptoms, then a good start to having a better tool has been made.

[fas42]

1 hour ago, Paul R said:

But in this case, why would a file sound different the second time it is played?  It is not like it is being copied or something. Even if it was, it is a digital file and will simply not experience degradation, no matter how many generations of copies.  So something is happening for sure. If it is listener familiarity, then waiting 90-180 seconds before playing it the second time should “eliminate the differences” - or perhaps as many as 300 seconds will need to elapse. If there is a real physical change in the equipment, then the equipment should be left playing during the wait period, perhaps with the volume muted. 

 

 

 

Because everything matters, . The waveforms in all the electronics are constantly changing, even in the supposed DC levels, because of what happened just prior, and then in the current moment - at a physics level it can't be any other way, because that's the nature of things ... .

 

Now, the theory is that "this sort of stuff doesn't matter!" - but everything I've looked at over the years says otherwise; our ears are too sensitive to tiny anomalies - and the gear is just not engineered well enough, many times, to reject these variations, that we can detect with our hearing. It shouldn't be audible, but it damn well is ... .

 

I was quite happy with the CD player, my first, until one day, just like Jim, I noticed something - Hey! I just restarted that track after playing a few seconds, and it sounds different! What's going on!! That was a start of a major exercise, exploring every variation of kicking off the playing of a new disk - I spent many days exploring this - and finally settled on a ritual that seemed the best method. An annoying thing to do at first - but it became habitual; just part of a pattern.

 

Later machines I used seemed not to have this; the current, quite old NAD CDP gets enough right, so far, for me not to worry about more subtle issues - though I will note one habit I have; I shut the drawer with the CD in, then re-open, and lastly press play, to shut again and start the music. Why? Because at one point I found it made a difference - is it still necessary, now?  I don't know - at some point when the SQ is at a really worthwhile level I'll do some more experimenting ...

 

 

[fas42]

1 hour ago, BrokeLinuxPhile said:

I'd put money on things being physiological/psychological more than a physically measurable phenomenon.  Superstition comes to mind, easy to convince yourself something brings good luck.  Or in this case, better sound.    There could be engineering reasoning behind it although much less likely IMO.  It would be a huge amount of effort to find the root cause either way and would the end result be worth all that effort?  Diminishing returns. 

 

If it sounds good, do it I say.

 

Nope. It's just like the telephone situation now being brought up - a little defect somewhere in the system brings the mechanism to its knees; a circuit can effectively stretch around the world - but it's still a circuit ... that little bit of moisture in a junction box way, way, away - does the damage.

 

Audio people believe in Santa Claus  - toss together expensive, impressive looking gear; and by golly, it's gotta sound good!! Ummm, no ... that "bit of moisture in the junction box", out of sight, doesn't give a damn for how fancy the rig appears - and the SQ will be below par ...

 

Yes, it's tiresome to sort out why a setup is not sounding up to scratch - but throwing money at it, increasing its bling quotient, or technobabble ingredients, is not exactly a smart approach ...

[fas42]

25 minutes ago, BrokeLinuxPhile said:

But the junction box full of water can always be found using a sound engineering approach.  It's noise, and can be triangulated, found, and repaired.  It's just a question whether or not it's cost effective to fix most of the time.  It's also erosion of quality over time, it used to work well and now not so much. 

 

And its works exactly the same in audio. Yes, it's a type of noise, but far, far more subtle - instead of sparkling, lifelike sound you get a flatness, deadness, edginess with treble; the quality of 'naturalness' is missing.

 

Quote

 

Here we are talking about a sense of 'sounds better' right from the get go without decay or breaking.  Or explainable noise even coming in from anywhere.  We are talking about restarting a single track from a CD and it sounding better.    Perhaps something is going on inside the machine that could cause that, but it's not the most likely culprit.  There would have to be a functional delta between starting a track fresh and hitting the back arrow button from either a hardware or software design standpoint.  It would cost more to do, take longer to develop, and you are always going to have 2 situations, one sounding better than the other.  Not saying it's impossible, just would not make much sense to do.

 

I'd put more money on physical changes inside the ear, call it fatigue or "calibration" to a new source track.

 

A high likely culprit are power supplies. Loading the CD, and initiating the pick up laser requires significant current draws, meaning that the transformer, etc, waveforms are different from stable playing status - replaying the track is giving all of the power supply circuitry a touch more time to fully restabilise; enough to make a difference.

 

Obviously engineering can make all these behaviours go away. But first the designer has to be aware that these issues can exist; if he doesn't, then it's a toss of the dice whether a particular unit will show signs of audible variations.

 

Having done a bit of experimenting in this area, I can quite easily say most power supplies in audio equipment are not good enough - yes, they nominally do the job, but their misbehaviour is often extremely obvious, in the loss of important SQ.

[fas42]

2 minutes ago, Ralf11 said:

actually it already has a name - Kal trotted it out just a week or so ago

 

remember the "sweet spot" is after neural accommodation, but before listening fatigue

 

The mark of competent playback sound is that it's instantly in the "sweet spot" - and that it never falters to become fatiguing - one of the many reasons to chase this realisable goal.

[fas42]

31 minutes ago, sandyk said:

 

Not bloody likely ! 

Even the poorest power supply should have fully recovered even before the short silent period at the beginning of the track has finished ,let alone affect the following audio for even a second or 2..

 

"Should" is the operative word ... something needs time, or some nudging, to settle into the optimum electrical state for best replay quality; what it is most likely will vary per design, and model - there won't be a unique answer. I recall that I immediately hit pause after play, and left it like that for about 30 secs - the disk was spinning, the laser was on target; it was just hovering on a single read spot - and then I let it off the hook...

 

Yes, I'm certain there will players without issues - my unit that had the behaviour was a well made item from 1986; early days for digital, .

[fas42]

14 hours ago, sandyk said:

Frank

 You are grabbing at straws !

This is easily verified by checking the supply rail voltages.

Alex

 

Alex, I'm afraid it is the silly little things that matter - checking supply voltages for the precise nature of the noise that exists on them, something that will constantly change, depending upon what the unit and its electrical surroundings are doing, is going to be difficult to do, and merely tells you whether there is a chance of some sort of interference effect being in the pictue ... what really needs to be solved is that the circuitry that takes care of the audio signal is not affected by what's going in its environment, outside of what it sees as the usual input.

 

If the sound quality changes, unexpectedly, then there is some cause. I would like to be able to punch a time card, for the periods spent over the years tracking down "what's gone wrong" when a rig has lost its current optimum SQ. Quite often it's just stupid little things - I make lots of highly temporary alterations to things, to check whether some factor matters; and sometimes these "come undone", partially. I rarely make something 'permanent', unless I'm 100% certain that doing the mod is absolutely key to the best sound.

[fas42]

11 hours ago, Miska said:

 

Difference is that when you start playback, OS disk cache will start pulling in the data into RAM. You stop and it's still there for a while, then you start again and at least part of the data is pre-cached. However, after couple of seconds of playback the OS would have already pulled the file into disk cache anyway. Assuming you have enough spare unused RAM. So any difference disappears at the point where both playback cases reach the same level of caching. Which is roughly couple of seconds into playback.

 

 

 

An exercise I did some time ago was to organise a good media player for my HP laptop. The usual suspects were hopeless - foobar amongst them. Media Monkey turned out right for me - and it was pretty obvious why: watching the resource usage monitor showed how much sharper MM was in not using CPU cycles, and how the access to the drive was done in short spurts - its footprint on the m/c was as little as possible, as a function of time.

[fas42]

4 minutes ago, BrokeLinuxPhile said:

 

Start track, pause and wait, and repeat track.  Sounds better second time around, on any digital device.  That's according to the OP, yourself, and others.  For any competent engineer, 75% of the work is complete right there.  According to what I'm reading here, you don't need a particular brand/model/anything, just plug your stuff in and you'll hear it every time, right?

 

 

Where have I said that? I haven't felt the need to do that procedure for years - what I have said is that it will depend ... the annoying thing about audio, , is that there are very few generic answers; in the same way as for cars, every time there is a problem there is an excellent chance that the solution, or solutions, will unique to the particular system - so, step 1 is to see if there's something in it for one's own case.