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24/192 music downloads are silly

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Re: 24/192 music downloads are silly

#311

Post by aidenn0 »

nkurz wrote: post #148
aidenn0 wrote: post #135

Earlier quoted context omitted.

> I'd probably make the bet that there exist certain 24-bit sound files that certain listeners can discern from the same sound file that has been downsampled to 16-bit. I would take you up on that bet. This has been tried before, and no difference was found, even when dithering wasn't used! The noise floor on 16 bit audio is around -96dB. There are very few HiFi systems that can manage that. Even in the highly unlike…

I probably should have written 16/44.1 vs 24/192, since I was thinking mostly of the waveform 'beat' interactions as shown in the linked video. Do you feel those are also indistinguishable? I can't afford an actual bet on it, but I'm interested enough to explore a bit and see what I can find.

1) I don't believe ultrasonic beat frequencies are by themselves audible (though I could be wrong about this).

2) It is possible to exploit nonlinearities in air to make audible sounds from ultrasound, but IIRC levels above 100 dBSPL are required. I think Disneyworld has an attraction that uses this.

3) It is highly likely that an arbitrary sound sample will sound different on playback if you add e.g. an 80kHz tone, as harmonic distortion of amplifiers and speakers tends to increase with frequency. This is generally considered a bad thing though, as it is a difference that would not be heard by a live listener.

[edit] Wikipedia link for #2: http://en.wikipedia.org/wiki/Sound_from_ultrasound

To understand how this works, consider that the speed of sound in air varies with air pressure. Furthermore sound is a pressure wave. Hand-wavingly this means that a sufficiently intense sound wave will alter its own propagation speed, which will in turn cause all sorts of interesting effects.

An analogous effect for light is used in many green lasers: some piezoelectric crystals will vary their index-of-refraction when an electric field is applied; a sufficiently powerful laser will generate a strong enough electric field. This can be used to frequency double infrared lasers into visible light.

Re: 24/192 music downloads are silly

#313

Post by alkonaut »

astrange wrote: post #108
alkonaut wrote: post #89

24bit absolutely makes sense in the age of streaming devices pushing sound to digital inputs on powered speakers. Simply for convenience reasons I want to adjust the playback volume already at my phone. I have no analog volume control (or rather, it's a configuration knob you set up once) If you play back a sample at 1/8 the volume, you still have 21bits of range from a 24bit sample. Playing a 16bit sample at 1/8 vol…

You might want a high bit depth audio stream if you were seriously boosting the volume, but not if you were lowering it. At most you might want a 24bit DAC. And if you can't pass an ABX test, then you don't really want it. Can you?

Why would s higher range not be good for lowering the amplitude? If you divide the samples in a 16bit stream by e.g 16 that means losing several bits of range. Surely if a 12bit dynamic range was perceived as being just as good as 16bits then we'd have that to begin with?

To be clear, when I say "lower the volume" I mean lowering the amplitude of the digital samples, passing them through a high quality dac and amplifying. I.e sliding the volume slider down on a iPhone using AirPlay to a Toslink->amp.

Re: 24/192 music downloads are silly

#314

Post by alkonaut »

ferongr wrote: post #161
alkonaut wrote: post #89

24bit absolutely makes sense in the age of streaming devices pushing sound to digital inputs on powered speakers. Simply for convenience reasons I want to adjust the playback volume already at my phone. I have no analog volume control (or rather, it's a configuration knob you set up once) If you play back a sample at 1/8 the volume, you still have 21bits of range from a 24bit sample. Playing a 16bit sample at 1/8 vol…

A 24bit digital format doesn't mean the DAC actually has 24bit of SNR. Hell, most DACs in computers, phones and the like struggle with producing 16 bits. Not to mention that even if you had that headroom, when approaching the threshold of hearing would mean that you wouldn't be able to tell a difference at lower volumes.

assuming a signal is played at "normal" listening volume after first being attenuated by 1/8 digitally (samples shifted 3bits down) and then passed through a high quality dac and amplified, are you saying the difference between 16 and 24 bit streams would be inaudible or nearly so? That to me sounds surprising. That seems to imply that the difference to playing the 16 bit stream unscaled (No digital attenuation and 8x on the analog side) would also not be hearable?

Re: 24/192 music downloads are silly

#315

Post by JetSpiegel »

copperx wrote: post #90
IvyMike wrote: post #44

Earlier quoted context omitted.

Let's do the math. If I didn't screw it up (and I probably did), an 8k iphone 6 would be around 1600 dpi.

Imagine being able to use a physical magnifier to see more information on the screen. Wouldn't that be great? at least for a curious child?

It's not like a smarthphone has that much extra processor and battery to waste.

Re: 24/192 music downloads are silly

#316

Post by black2night »

Stratoscope wrote: post #253
Lazlo_Nibble wrote: post #228

Earlier quoted context omitted.

Uh, no. Bit-perfect ripping is trivial and routine, and tools like the AccurateRip DB (which has checksums for around three million different titles you can use to verify the checksums on your own rips) and the CUEtools database (which has recovery records you can use to correct bit errors on your own rips) prove it. I routinely get bit-accurate single-pass high-speed rips--no "paranoid" settings or re-reads--of disc…

Oh sure, your rips may be perfect at the bit level, but how do you know that they're free of sub-bit quantization that isn't detectable by electronic circuits but can be heard by the human ear? This sub-bit jitter and interference can travel along with a digital file and sneak right past your ordinary bit-level error detection and correction, no matter how lossless you make it. That's because these errors aren't visi…

Thank you so muuuuuuuch for the uncontrollably laugh i'm having now

Re: 24/192 music downloads are silly

#317

Post by hueving »

psychometry wrote: post #303
Stratoscope wrote: post #253

Earlier quoted context omitted.

Oh sure, your rips may be perfect at the bit level, but how do you know that they're free of sub-bit quantization that isn't detectable by electronic circuits but can be heard by the human ear? This sub-bit jitter and interference can travel along with a digital file and sneak right past your ordinary bit-level error detection and correction, no matter how lossless you make it. That's because these errors aren't visi…

Flawless satire.

Something about it being on HN also makes you assume a post isn't a joke starting out so I read for a lot longer before I realized what was happening.

Re: 24/192 music downloads are silly

#318

Post by Htsthbjig »

I have worked a lot with audio programming and while most of the article is right in what is known, it could be wrong at what we don't know. Technical myopia(you see too much of what you know but you don't see the big picture).

We are using HDR in pictures even when the eye could not differentiate between HDR colors because it adapts to the general luminosity of the image but CAUTION the general luminosity level affects lots of biological cycles like the circadian rhythm.

In normal pictures we discard this info, but this info is enough for a person to differentiate a picture from a real image in the real world.

Also natural sensors work different than our eyes and ears.

This difference makes HDR a necessary because we can see a huge shadow along with an illuminated area at the same time because our cones in the retina adapt locally, but if you make a single picture we can only choose to picture the bright areas, making shadows too dark, or choose the shadows making the bright areas appear too white.

Artificial sensors linearize over a fixed level. Nature sensors are really continuous exponential, even touch.

The same happens with our ears. So you are doing an spectral analysis using an arithmetic frequency decomposer called the FFT?

Well, sorry to burst your bubble but the cloclea frequency analysis runs circles around anything we have. It does a geometric analysis, and also does it locally. Using just a single tone as an example is a fallacy. Most real sounds are not a single tone but changes in lots of frequencies at the same time.

The law of diminishing returns applies to sound and video, we have a good enough experience for what we want to do, but by no means it is perfect.

Ask John Carmack that is trying to create an immersive experience. Sound is one of the big problems. Yes, you can understand the sound, but you know that it is not the real sound you hear in the real world.

Re: 24/192 music downloads are silly

#319

Post by hueving »

storrgie wrote: post #250
dcohenp wrote: post #223

Earlier quoted context omitted.

It's one thing when you plop down a ton of cash for something where you embrace the "silliness" or whatever makes it special (e.g. buying exotic cars with monstruous engines to drive them into traffic). It's another, however, believing something is objectively "better" because it cost more; e.g. spending money on Monster Cables thinking you can hear a difference. In audio, you have people who love vinyl because they…

I completely get that as I personally prefer to collect Old Stock vacuum tubes for my listening purposes ( http://imgur.com/a/INXVX ). I just think folks should be left to their own devices to enjoy an avocation as they please. Trying to defend something through completely subjective argument is silly, I've a hard time discussing 'objectively better' technology with audiophole folks, but if someone said 'I like this…

>I just think folks should be left to their own devices to enjoy an avocation as they please.

Only if they shut up and never tell other people that should be listening at 24/192. However, the people being complained about here spout nonsense like that all of the time.

Re: 24/192 music downloads are silly

#320

Post by Confusion »

btown wrote: post #57
yclept wrote: post #52

Earlier quoted context omitted.

If there's psychological phenomena that make them enjoy it more, what's the issue?

And there are jobs created for engineers who design that equipment - simultaneously recycling more money in the economy and contributing to the statistics of STEM job prospects! Everybody wins!

Broken window fallacy.
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