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High Playback Sampling Frequencies
Reply #50
The increasing popularity of high playback sampling rates could be attributed to a not entirely irrational desire for margin (overkill).


Good point.

Using higher sampling rates is virtually a no-cost option today. AFAIK every decent converter that is designed for use in audio production work has sample rate options up to 24/192. The extra storage and processing required by the need to handle integer multiples more data are now readily available. This even extends to highly portable equipment.

The same can be said of the use of longer data words.

Neither of them are generally effective at actually producing better sound quality, but as the thinking goes - since: "They cost me nothing and give me the perception of reduced risk..."

  • Woodinville
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High Playback Sampling Frequencies
Reply #51
I'm still confused as to why studios use really high sampling frequencies.  I have a vague understanding of why higher bit depths might be needed for adujsting levels, but I don't get why they need higher sampling rates.


Because even professional recording engineers can be subject to the same magical thinking and lack of scientific rigor we commonly see among audiophiles. It's just as easy to start a religious war about this stuff in a recording forum as it is in a hi-fi forum.

--Ethan


Actually, there are occasionally (note the qualification) reasons to be working at a higher sampling rate. If you must do nonlinear processing for some reason, a higher sampling rate helps ensure that aliasing of harmonics does not happen.  This kind of processing is, unfortunately, sometimes necessary. While it is possible to increase the sampling rate for that plugin, how many times do you want to run your signal through the 20kHz antialiasing filters?  Perhaps better to run it once at the end?  Of course, a plugin that accepts lower sampling rate should do upsampling if it must, etc.

Completely dismissing the idea is not appropriate. Just mostly dismissing it is reasonable.

Having said that, indeed, there is a lot of magical thinking in some of the production folks.
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J. D. (jj) Johnston

  • Woodinville
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High Playback Sampling Frequencies
Reply #52
Good point.

Using higher sampling rates is virtually a no-cost option today. AFAIK every decent converter that is designed for use in audio production work has sample rate options up to 24/192. The extra storage and processing required by the need to handle integer multiples more data are now readily available. This even extends to highly portable equipment.

The same can be said of the use of longer data words.

Neither of them are generally effective at actually producing better sound quality, but as the thinking goes - since: "They cost me nothing and give me the perception of reduced risk..."


Actually, using longer words for capture can create better sound quality, by allowing a "documentation recording" at a known gain, rather than a recording level that is near-peak at its highest.
-----
J. D. (jj) Johnston

High Playback Sampling Frequencies
Reply #53
Actually, there are occasionally (note the qualification) reasons to be working at a higher sampling rate. If you must do nonlinear processing for some reason, a higher sampling rate helps ensure that aliasing of harmonics does not happen.


Sure, and de-clicking software can work better when LPs are recorded at a higher sample rate, because the click rise-times are faster than the music.

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Just mostly dismissing it is reasonable.
Having said that, indeed, there is a lot of magical thinking in some of the production folks.


Exactly, I see this all the time at the womb and gearslutz.

--Ethan
I believe in Truth, Justice, and the Scientific Method

  • wakibaki
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High Playback Sampling Frequencies
Reply #54
Neither of them are generally effective at actually producing better sound quality, but as the thinking goes - since: "They cost me nothing and give me the perception of reduced risk..."


Precisely.

I look forward to the day when both higher sample rates and greater bit-depths are widely adopted, not because I feel they offer an improvement in SQ, but because I think (admittedly perhaps mistakenly) that they will offer less opportunity for the sowing of FUD in the consumer.

w
wakibaki.com

  • saratoga
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High Playback Sampling Frequencies
Reply #55
I look forward to the day when both higher sample rates and greater bit-depths are widely adopted, not because I feel they offer an improvement in SQ, but because I think (admittedly perhaps mistakenly) that they will offer less opportunity for the sowing of FUD in the consumer.


Ha, I wish.  The day everyone has 96k/24 bit audio is the day they start selling 192k remasters

No matter how big of a number you have people will eventually find a way to bullshit about a bigger one.

  • wakibaki
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High Playback Sampling Frequencies
Reply #56
No matter how big of a number you have people will eventually find a way to bullshit about a bigger one.


I understand how you feel, but IMO it is only a feeling. The less people act out of their hopelessness the greater the likelihood things will change. Once we get to 192k it'll be really hard to argue the necessity for anything more.

w
wakibaki.com

  • knutinh
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High Playback Sampling Frequencies
Reply #57
I understand how you feel, but IMO it is only a feeling. The less people act out of their hopelessness the greater the likelihood things will change. Once we get to 192k it'll be really hard to argue the necessity for anything more.

It is hard to argue the necessity of anything more than 44.1k.

This does in no way inhibit glossy audio magazine writers from claiming audible limitations of 44.1 to be a fact, and anyone questioning it to be evil.

192kHz, 384kHz,... they will never stop.

Imagine the consequences if they actually talked about the stuff that matters? Such as mastering practices, loudspeaker/room, multichannel? If they did that and limited the use of meaningless artsy words, I might buy their magazines.

-k
  • Last Edit: 22 February, 2012, 02:01:22 AM by knutinh

  • icstm
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High Playback Sampling Frequencies
Reply #58
In fact, before I sample to 44.1, I could process my signal at the higher sampling rate to not include frequencies above 22k.

Which is called a low pass filter that acts as an anti-aliasing filter.

My understanding is that an anti-aliasing filter is applied prior to digitisation, to remove the ambiguity that arises from sampling.
What I am suggesting within the digital domain. In the digital (sampled) domain, the probablems that others have pointed to around anologue low pass filters do not apply.

Right, I see that we were talking about removal of greater than Nyquist in the digital domain prior to reconstruction.  Still lots of concern about anti-aliasing/anti-imaging, but not a lot of objective data demonstrating that it's been a problem over the last decade if not longer?
I agree, which was the reason for my OP. I agree that DAC use oversampling (as the post below yours points to) but that does not take away from the fact that 16bits per channel of information sampled at 44.1kHz is a suitable way to store music and is not improved upon by higher formats. Nothing posted here has changed my beleive and some posts have provided some evidence to support this position.

  • xnor
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High Playback Sampling Frequencies
Reply #59
My understanding is that an anti-aliasing filter is applied prior to digitisation, to remove the ambiguity that arises from sampling.
What I am suggesting within the digital domain. In the digital (sampled) domain, the probablems that others have pointed to around anologue low pass filters do not apply.

It's also applied in the process of up- or downsampling to ensure that the sampling theorem is satisfied. Lets say you record at 88.2 kHz, now if you want to throw away every second sample you have to filter the signal with a lowpass first (usually done using a steep linear phase FIR), else the ambiguity you mentioned (aka aliasing) kicks in. Sure, compared to analogue filters there is no phase shift, etc.
"I hear it when I see it."

  • wakibaki
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High Playback Sampling Frequencies
Reply #60
...the fact that 16bits per channel of information sampled at 44.1kHz is a suitable way to store music and is not improved upon by higher formats.


QED. Despite the enormous hooraw raised in some quarters this can be taken as a fact. No manufacturer or researcher has succeeded in demonstrating the contrary in double blind testing, the most recent authoritative study being that presented in the 2007 issue of the Journal of the Audio Engineering Society (Volume 55, Number 9) by E. Brad Meyer and David R. Moran.  Differences in noise floor become perceptible only when the volume is turned up to unrealistic levels.

w
wakibaki.com

High Playback Sampling Frequencies
Reply #61
No matter how big of a number you have people will eventually find a way to bullshit about a bigger one.

Exactly. Some people prefer to believe in magic. They may even be wired that way. They wanted to believe when watching the X Files years ago, and they want to believe in magic today too. Education is our only hope. I've always thought that school kids should be taught logic and consumerism starting in in the first grade. Seriously.

--Ethan
I believe in Truth, Justice, and the Scientific Method

  • db1989
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High Playback Sampling Frequencies
Reply #62
I've always thought that school kids should be taught logic
To which I would add ‘the’ scientific method, and skepticism/critical thinking, and the appropriate amount of geography necessary to appreciate the environment and its other inhabitants, and probably many more. English, maths, and French (in my case) are fine, I guess, but this is nowhere near enough.

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and consumerism
This might be where we diverge in opinion! If you mean ‘not buying total crap’, I agree; but I in no way support any teaching of consumerism as a lifestyle, vehicle of progress, bastion of civilisation, or whatever they’ve been trying to portray it as since the first third of the 19th century. What I think we need is to buy less crap, ideally to buy no crap (read: just useful/necessary things), and perhaps to try to think about something to put in place of buying altogether. But I digress!

  • Woodinville
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High Playback Sampling Frequencies
Reply #63
My personal belief (and I make no apologies in presenting it and would be honored to be credited in its fulfillment) is that the audiophile rags and their faith-based minions aren't going to stop pushing for more once they've reached some arbitrary threshold.


I think it goes well beyond the magazines. The manufacturers of equipment like http://www.lessloss.com/firewall-p-196.html and http://www.bybeetech.com/ourtech.asp are not going to "stop that" regardless.

A couple of interesting quotes from those sites, first Bybeetech:
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During transit through the Quantum Purifier, quantum noise energy is stripped off the electrons, streamlining their flow through ensuing conductors.

and Less Loss:
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In traditional filtering networks, very high frequency noise circumvents capacitors and coils. Without using such traditional filtering elements, the Firewall is a direct enhancement to the unique filtering technology employed in the LessLoss DFPC Signature power cord.


:facepalm:
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J. D. (jj) Johnston

High Playback Sampling Frequencies
Reply #64
What I meant originally was that by converting to a new sample rate, some of the new samples will be have a position in time in between old samples, and as such require some computational decision to be made on their value (interpolation or rounding or prediction or whatever system is in place). Whatever the process involved, the new values will have a lesser accuracy and the signal will have been degraded.


The process is called interpolation, and no, thats not generally a problem.  Interpolation can be done with essentially unlimited accuracy, such that it is widely regarded (assuming proper implementation of course) as having no impact on quality.  Do a search, this has been discussed to death and in far more detail then I have time for.


I'm very surprised to hear that resampling can be achieved with limitless accuracy, however if it's been done to death on here then I can accept that there must truth in what your saying. With the kind of real world examples that I'm talking about, samplers etc, there is not limitless accuracy. I know this is a sweeping statement with no ABX tests, but with that caveat I continue to assert it because there is truth in it. My main concern about sampling is preserving the frequency content when pitching down.

Ill try to elaborate on the suggestion that granular time stretching can benefit from a higher sample rate. When time stretching, the sound is split up in to little grains of the ms magnitude. The larger the grain, the more noticeable the granulation when the tempo is lowered


Since any time stretch algorithm can set the sampling rate as high as it likes for processing purposes, it doesn't really matter what the input sampling rate is.


Yes any algorithm could have good grain size control and up sampling, but I'm talking about the real world context of ableton live and samplers, which do not have these controls, and which do sound significantly different at higher sample rates (I understand ABX or somesuch is required for such sweeping statements - ill endeavour to supply some).

Similarly, when sampling a sound and then playing it back at a different pitch there is benefit to processing at a higher sample rate. Samplers re-pitch sound, and this is almost always done by resampling. If the sample contains audio up until half the sample frequency then it follows that a 48kHz sample played back at the original pitch has an upper limit of 24khz. If this is played back two octaves lower then the upper limit of the sound spectrum is 6khz.


Well yes, for recording ultrasounic information, higher sampling rates are quite obviously useful.  But we're talking about music.  Not, bat calls.  Music is generally assumed to occupy the range of frequencies humans can here, and for those 48k is quite sufficient.  If you wish to record things that humans cannot hear, then by all means go buy a 1MHz A/D.


Glad you agree on this one, it's my main point. Also, writin this on the iPhone I'm not sure I could contend with typing any more! It's a bit fiddly. The arguments you've presented definately give me some food for thought, ill continue to read on.



Sorry original poster, I've taken this off topic. Half the time I'm listening to spotify, so that shows you my stance. Also I'm still buying vinyl, so judging my what I perceive to be the prevailing thoughts on this forum I can be disregarded as a Luddite anyway.

  • saratoga
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High Playback Sampling Frequencies
Reply #65
What I meant originally was that by converting to a new sample rate, some of the new samples will be have a position in time in between old samples, and as such require some computational decision to be made on their value (interpolation or rounding or prediction or whatever system is in place). Whatever the process involved, the new values will have a lesser accuracy and the signal will have been degraded.


The process is called interpolation, and no, thats not generally a problem.  Interpolation can be done with essentially unlimited accuracy, such that it is widely regarded (assuming proper implementation of course) as having no impact on quality.  Do a search, this has been discussed to death and in far more detail then I have time for.


I'm very surprised to hear that resampling can be achieved with limitless accuracy, however if it's been done to death on here then I can accept that there must truth in what your saying. With the kind of real world examples that I'm talking about, samplers etc, there is not limitless accuracy. I know this is a sweeping statement with no ABX tests, but with that caveat I continue to assert it because there is truth in it. My main concern about sampling is preserving the frequency content when pitching down.


If you're getting some loss of quality resampling, then your software is badly broken.  Take a look on this forum.  There are literally more then a dozen pieces of software you can choose from that will give you accuracy far beyond what any DAC can reproduce.  Digital resampling is not a particularly difficult problem.  There is no excuse for using bad software to do it this day in age.

  • icstm
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High Playback Sampling Frequencies
Reply #66
[In response to the above post:] That is what I was (badly) trying to say earlier. I see no problem resampling in the digital domain and thus no problem going from higher sampling rates to 44.1k for final storage and playback.

Sorry original poster, I've taken this off topic. Half the time I'm listening to spotify, so that shows you my stance. Also I'm still buying vinyl, so judging my what I perceive to be the prevailing thoughts on this forum I can be disregarded as a Luddite anyway.
no problem, but i like the fact you use Vinyl AND spotify... 
  • Last Edit: 23 February, 2012, 05:02:47 AM by db1989

High Playback Sampling Frequencies
Reply #67
I think it goes well beyond the magazines. The manufacturers of equipment like http://www.lessloss.com/firewall-p-196.html and http://www.bybeetech.com/ourtech.asp are not going to "stop that" regardless.


Yes, but they'd stop making nonsense if people stopped buying it. That's why I mentioned logic, education, and consumerism.

--Ethan
I believe in Truth, Justice, and the Scientific Method

High Playback Sampling Frequencies
Reply #68
Define "magical thinking".

knutinh already gave one answer, but this is too important to let pass so quickly. To my mind, magical thinking is behind most of the world's problems. A simple example is a friend of mine, a young woman who truly believes that food tastes better when the chef has love in his heart. Forget that love is a brain function, showing her lack of knowledge about basic physiology. I asked her by what chemical process could "love" affect the taste of food. She had no answer, but continues to believe anyway. This points up another problem with believers: They will not be convinced no matter how compelling the counter arguments. Another person I know barely earns enough to get by, yet spends a fortune on "holistic" products for her two cats.

But magical thinking goes way beyond harmless human foibles like this. If the government spends $10 Million to study whether pornography is harmful, and the study says No, that should be the end of it. Instead, they spend $10 Million more, several times, trying to get the answer they're sure is right. But that still pales compared to all the wars based on "My god is better than your god," which to me is the ultimate example of the harm of magical thinking.

Sorry for the OT rant, but I feel very strongly about this subject.

--Ethan
I believe in Truth, Justice, and the Scientific Method

High Playback Sampling Frequencies
Reply #69
Loved food does generally taste better. Now define love

  • greynol
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High Playback Sampling Frequencies
Reply #70
Let's keep this on-topic, please.
13 February 2016: The world was blessed with the passing of a truly vile and wretched person.

Your eyes cannot hear.

High Playback Sampling Frequencies
Reply #71
Sorry for the OT rant, but I feel very strongly about this subject.

Being among fellow skeptics is one of the reasons I am on HA

High Playback Sampling Frequencies
Reply #72
Magical thinking at its best...

http://www.musicalsounds.us/PDF/AADACI.pdf

Is that even possible?

  • 2Bdecided
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High Playback Sampling Frequencies
Reply #73
Magical thinking at its best...

http://www.musicalsounds.us/PDF/AADACI.pdf

Is that even possible?
That's BS - but more frightening is that people are asking for (and "getting") 32-bit DACs...
http://www.diyaudio.com/forums/digital-sou...-bit-dac-4.html

Cheers,
David.

High Playback Sampling Frequencies
Reply #74
^^^ LOL at this in particular:

"a new 66 bit/1536 kHz concept"

Yeah, what a concept. I'm surprised they stopped there. If only they designed their box to use 68 bits at 1592 KHz I'd buy one in a heartbeat.

--Ethan
I believe in Truth, Justice, and the Scientific Method