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24/192 music downloads make no sense

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Re: 24/192 music downloads make no sense

#141

Post by derefr »

alkonaut wrote: post #132
ska wrote: post #55

Earlier quoted context omitted.

The article is pretty clear about this too - higher bitdepths and sampling rates can be quite useful in mixing and recording situations. They're pointless for playback.

Doesn't that depend on what type of playback you are doing? More and more playback these days is done via digital transfer with the volume set in software at the sending end, to amplifiers at fixed volume, such as many multi-room systems. If I airplay a song from my iPhone and have the volume at 50% set in software, then a few extra bits can help. Not sure if it makes a noticable difference, but it's a digital mixing…

An aside: I've never understood why the logic around digital signal-path volume adjustment isn't "keep the volume number around all the way to the end; throw the signal through the DAC at 100% gain, and then attenuate the signal on the analogue path using the digital volume setting." Uses more power, I suppose.

Re: 24/192 music downloads make no sense

#142

Post by jacobolus »

Sharlin wrote: post #107
msandford wrote: post #80

Earlier quoted context omitted.

> That is really the central issue. It's much like imaging since the time of Ansel Adams: the sensor can capture more dynamic range than the human eye can experience. That's not really true. Dynamic range refers to the difference between the biggest value that isn't clipped and the smallest value that isn't rounded to zero. The human eye is a logarithmic detector, cameras are linear. The only reason HDR is a thing is…

The instantaneous dynamic range of the human eye is estimated to be less than eight stops. Both film and modern camera sensors can capture much more than that. The reason we're able to adequately perceive scenes with 12+ stops of dynamic range is that our visual system does continuous integration and reconstructs an HDR "mosaic" in real time. HDR photography is required in situations where even the 12-14 stops that a…

Nice photo prints can typically show something like 100:1 to 200:1 contrast (~6.5–7.5 stops) between white and black, or at the top end, some dye transfer prints under carefully controlled lighting can get up to about 500:1 (9 stops).

Nice computer displays (and mobile device displays) without glare and with the brightness cranked all the way up can get up to something like 9.5–10.5 stops.

Of course, that range still pales in comparison to the contrast between shadows and highlights on a sunny day, which can be more like 16+ stops.

Re: 24/192 music downloads make no sense

#144

Post by Zitrax »

cthalupa wrote: post #126
lawnchair_larry wrote: post #30

Earlier quoted context omitted.

Vinyl actually has far less fidelity. You also physically change the recording every time you play it back. Even on the same equipment, no two plays of a vinyl LP sound exactly the same, unlike digital. This fact alone should cause you to question your subjective experience. You have no idea what part of that system was contributing to what you found pleasant. Someone who knew what they were doing could probably buil…

>Vinyl actually has far less fidelity. Vinyl mastering is sometimes better than CD mastering though, due to the loudness war. I would love to sell my turntable and vinyl collection and rely purely on digital formats. Takes up less space, technically superior format, etc. But one thing keeps me buying vinyl: AWFUL mastering on CDs. A significant portion of LPs are released with more normal mastering on the vinyl, whil…

How do the versions on streaming services compare, are they usually copies of the CD masterings ?

Re: 24/192 music downloads make no sense

#145

Post by squeaky-clean »

weinzierl wrote: post #104

Because digital filters have few of the practical limitations of an analog filter, we can complete the anti-aliasing process with greater efficiency and precision digitally. The very high rate raw digital signal passes through a digital anti-aliasing filter, which has no trouble fitting a transition band into a tight space. I always thought digital anti-aliasing filters were creatures from a fairy-tale world. Much ta…

The digital anti-aliasing filter can only ever work on a digital -> digital signal, but they're still useful in the analog->digital process.

> My understanding: If you have a an analog filter of a given steepness the only way to further reduce aliasing effects digitally is oversampling. Or less steep (cheaper) analog filter plus oversampling is the same as steeper (more) expensive analog filter. People tend to say digital anti-aliasing filters when they really mean oversampling

You're right, and it's actually both. The ADC can run at a much higher sample rate with a cheaper analog filter, and then that digital signal is again passed through a digital filter and downsampled.

Re: 24/192 music downloads make no sense

#146

Post by alkonaut »

derefr wrote: post #141
alkonaut wrote: post #132

Earlier quoted context omitted.

Doesn't that depend on what type of playback you are doing? More and more playback these days is done via digital transfer with the volume set in software at the sending end, to amplifiers at fixed volume, such as many multi-room systems. If I airplay a song from my iPhone and have the volume at 50% set in software, then a few extra bits can help. Not sure if it makes a noticable difference, but it's a digital mixing…

An aside: I've never understood why the logic around digital signal-path volume adjustment isn't "keep the volume number around all the way to the end; throw the signal through the DAC at 100% gain, and then attenuate the signal on the analogue path using the digital volume setting." Uses more power, I suppose.

That's how it should work. Not sure why it doesn't. Needs some updated standard for digital transfer I suppose. Updates to AirPlay, Toslink etc.

Re: 24/192 music downloads make no sense

#147

Post by detaro »

alkonaut wrote: post #132
ska wrote: post #55

Earlier quoted context omitted.

The article is pretty clear about this too - higher bitdepths and sampling rates can be quite useful in mixing and recording situations. They're pointless for playback.

Doesn't that depend on what type of playback you are doing? More and more playback these days is done via digital transfer with the volume set in software at the sending end, to amplifiers at fixed volume, such as many multi-room systems. If I airplay a song from my iPhone and have the volume at 50% set in software, then a few extra bits can help. Not sure if it makes a noticable difference, but it's a digital mixing…

Why woulda few extra bit in the source data help there? A DAC with more bits would, but that can easily be scaled from the existing data.

Re: 24/192 music downloads make no sense

#148

Post by multinglets »

This is clearly overkill, if you ask me, but let's not get too carried away with "44kHz 320kbps mp3 are always good enough and if you say otherwise you're a snakeoil-buying fool." For starters, there are people who can hear well into the 22kHz range. Mp3 is also based on a psychoacoustic model, and that model can be (and absolutely is) more accurate for some people than it is for others, and it is also subject to fundamental flaws (there are sounds that will always produce a compression artifact for even the latest encoders).

It drives me absolutely crazy when people start circlejerking over "those dumb ol' flac people." I don't care how much theory you think you have; you don't know what you're talking about.

Re: 24/192 music downloads make no sense

#149

Post by rubberbandage »

z3t4 wrote: post #136

I can hear insects and buzzing electronic devices, and my partner thinks I'm crazy some times. Thinking I might have golden ears I tested * my range and I could hear up to 18kHz. * http://onlinetonegenerator.com/hearingtest.html

Honestly, depending on your age, that still could be “golden” — I’m 31, I’ve taken very good care of my hearing, I’m very acutely aware of audio subtleties, and my hearing range tops out around 16.5KHz. The so-called standard upper limit of 20KHz really only applies to young children, which is why CD audio being able to reproduce frequencies of 22.05KHz is already beyond ideal, and calls for 48! no, 96!, no, 192! (or higher) is literally insane for playback.

Re: 24/192 music downloads make no sense

#150

Post by ubercow13 »

TheOtherHobbes wrote: post #134
ska wrote: post #55

Earlier quoted context omitted.

The article is pretty clear about this too - higher bitdepths and sampling rates can be quite useful in mixing and recording situations. They're pointless for playback.

No they're not. And no matter how many times this gets linked to on the Internet, it's still wrong. The basic problem: the quieter a sound or detail gets, the fewer bits of resolution are used to represent it. In 16-bit recording, there simply aren't enough bits to represent very low level details without distorting them with a subtle but audible crunchy digital halo of quantisation noise. In a 24-bit recording, ther…

For a properly dithered recording, bit depth is exactly equivalent to noise floor. If low-volume details are lost in 16 bit recordings it is because their volume falls near or below the noise floor imposed by the 16 bit recording. 16 bits is good enough because the noise floor is low enough to be imperceptible to a human, if the gain of the recording is such that the full dynamic range available is used
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