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24/192 music downloads are silly

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Re: 24/192 music downloads are silly

#171

Post by leoc »

badsock wrote: post #118
nnnnni wrote: post #54

Earlier quoted context omitted.

There's also the fact that you can FEEL some sounds that you can't hear. Chris Randall of Sister Machine Gun (at least used to?) use a low-frequency generator at live shows to produce a sound that the audience could feel but not hear in order to make the music more intense. I suspect that you'd gain some of that effect with a larger bit size. ...or I could be completely wrong. Whatever.

The increase in sample rate to 192kHz only allows frequencies above 22KHz to be represented (i.e. no effect whatsoever on the low frequencies that you mention). Pushing the bits to 24 only lowers the noise levels (which at 16 are already demonstrably imperceptible). What you mention, though, points directly to what /will/ improve the quality of sound reproduction: speakers. It gets harder and harder to move that much…

According to this interesting-looking article here http://www.theregister.co.uk/2014/07/02/feature_the_future_l... the problem isn't frequency response but things like time delay, and it's not due simply to the very end but also to systems leading up to and around it like inaccurate crossovers and speaker cabinets that introduce time delay.

Re: 24/192 music downloads are silly

#172

Post by dietrichepp »

lmm wrote: post #132

You can't simultaneously say that you're dithering to represent low amplitudes while also saying you're keeping enough samples to capture all audible frequencies. Dithering doesn't create resolution out of nowhere, it sacrifices temporal resolution for amplitude resolution. It's also bad for compression (hence why modern video encodes are done at 10-bit even for output to 8-bit devices), and worse if you want to use…

> Dithering doesn't create resolution out of nowhere, it sacrifices temporal resolution for amplitude resolution.

Could you elaborate on that? As I understand it, dithering trades distortion for uncorrelated noise, under the assumption that the distortion is more objectionable than the noise. Where did you come to the conclusion that temporal resolution is affected? The temporal resolution is instead related to the frequency resolution.

I agree that 48kHz/24-bit is the most sensible for production, especially since (as you said) you don't have to worry about the levels too much. But when you master a track, you pay very close attention to the levels anyway, so those 8 extra bits don't do you any good. I think most people can't hear past 12 or 14 bits anyway, unless the audio has a particularly wide dynamic range.

Re: 24/192 music downloads are silly

#173

Post by astrange »

dTal wrote: post #165
astrange wrote: post #110

Earlier quoted context omitted.

MP3 has specific algorithmic weaknesses above 16khz[0] which even the highest legal bitrate can't cover up… sometimes. It's actually easiest to hear it with cymbals, or the old LAME sample "fatboy". You can just not use MP3 though. It's 2014! Use AAC! [0] http://wiki.hydrogenaud.io/index.php?title=LAME_Y_switch

I don't understand why everyone doesn't use Opus for anything. Damn thing is free, beats AAC for psychoacoustics, beats Speex for latency...

The early encoder releases were tuned for voice chat, not music, so the best rate control mode is CBR and it hasn't seriously been tested otherwise. It is pretty amazing considering it's only so good by accident!

Also, everyone is satisfied with AAC already, so there's no good reason to throw out your music collection or your HW accelerated decoding platform.

Re: 24/192 music downloads are silly

#174

Post by neonkiwi »

cozzyd wrote: post #141
nnnnni wrote: post #54

Earlier quoted context omitted.

There's also the fact that you can FEEL some sounds that you can't hear. Chris Randall of Sister Machine Gun (at least used to?) use a low-frequency generator at live shows to produce a sound that the audience could feel but not hear in order to make the music more intense. I suspect that you'd gain some of that effect with a larger bit size. ...or I could be completely wrong. Whatever.

Well, first of all there is no problem with encoding low frequencies here (we do all the time! like the fact that the notes are not all played at the same time...). What you feel is parts of your body resonating (because the low frequency sound is exciting modes of your body). This is unlikely to happen at high frequencies, partially because it would necessarily be much smaller parts of your body (see [0] for a diagr…

You hypothesized about tissue damage from ultrasonic excitation, so this tangential post may be of interest. Tissue damage from ultrasound is an intentionally-caused phenomenon being used (and experimented with) in some non-invasive medical procedures, where focused energy can locally ablate a tumor for instance. HIFU, high-intensity focused ultrasound, is the technique: http://en.wikipedia.org/wiki/High-intensity_focused_ultrasou...

Re: 24/192 music downloads are silly

#175

Post by tempestn »

anigbrowl wrote: post #124
threeseed wrote: post #78

Earlier quoted context omitted.

> Self-styled audiophiles are, by and large, idiots with way too much money plagued by magical thinking. Not just that. But the arrogance and fanboyism is rampant. God forbid you ever consider buying a Bose or Beats product.

Those are low-budget audiophile products, ie they are still marketed mainly to boost the ego of purchasers. There are three brands of headphones that pros use: Beyerdynamic (typically DT-100 or DT-770), Sennheiser (typically HD-5/650) and Sony (typically MDR-7506/9). Beyerdynamics have somewhat better isolation so they're more popular in music studios, Sonys are more comfortable when you have to wear them all day so…

From all the reviews I've seen, Bose noise-cancelling headphones are pretty much the best you can buy. Especially if you want earbuds (the QC20s). They're extremely expensive though. Do you (or anyone) have suggestions for alternatives?

Re: 24/192 music downloads are silly

#176

Post by bjornsing »

TL;DR, but skimming through an interesting problem comes to mind: The OP "orthogonalizes" the question of the sample accuracy's (24 vs 16 bit) and sample rate's (48 vs 192 kHz) impact on quality, answering one independent of the other. But even with my limited background in mathematics it's quite obvious that that approach is not entirely correct: the Nyqvist theorem only really applies when you have infinite sample accuracy. It would be interesting to see an analysis of how the two interact; i.e. how the discretization error impacts the highest representable frequency.

Re: 24/192 music downloads are silly

#177

Post by kevin_thibedeau »

errantspark wrote: post #18

I once spent ~2 hours explaining all of this (well maybe not all of it) to a friend of mine who was studying sound design at the time. He didn't believe me. I even transcoded some 24/192 FLAC Pink Floyd I had lying around and made him do a double blind test to show him that he'd prefer the slightly louder song every time, even if the louder song was 192kbps vs the FLAC. He did. He still doesn't believe me. He still t…

The DECT phone standard had to be marketed as "6.0" for the US market because non-technical people were trained to believe that 5.8GHz was better than 2.4GHz and a phone that ran at 1.9GHz would never sell in the US. This is the same thought process driving the audiophools' desire for bigger numbers regardless of reason. It doesn't help that the fundamentals of sampling theory aren't particularly intuitive.

Re: 24/192 music downloads are silly

#178

Post by bryans »

kstenerud wrote: post #127
janussi wrote: post #106

Earlier quoted context omitted.

You can't hear the difference between MP3 and FLAC? I'm sorry but either you're deaf or your equipment is very poor. Bad example.

I keep FLAC copies just so that I have lossless versions that I can convert into the lossy format du jour, but for actually listening, I mass-convert to lossy. I've listened to FLAC and properly encoded MP3 files (@192 and 160) on $50,000 audio equipment, and I can't tell the difference.

To put it simply and honestly, you are not paying enough attention. There is no human-discernible difference between FLAC and V0/320kbps. But implying that 192kbps and 160kbps are sufficiently perfect is somewhat ludicrous. You can still hear noticeable artifacts on cymbals at 192kbps. They will sound like an absolute mess of warbling, and all of the audio will be imbued with a slight tinge of white noise.

There is a reason the mp3 scene moved away from 192kbps, and it doesn't have anything to do with bandwidth availability. It's because 192kbps sounds terrible.

Re: 24/192 music downloads are silly

#179

Post by leoc »

The most interesting development in terms of surround audio may be the Oculus Rift. A number of people were working on combining high-quality VR HMD head-tracking with headphones and a spatial audio system http://www.mee.tcd.ie/thrive/ http://www.technologyreview.com/news/527826/microsofts-3-d-a... . Then Oculus licensed a spatial audio system itself http://www.roadtovr.com/oculus-rift-dk2-realsense-3d-audio-p... and announced that the first consumer version of the Rift would have integrated headphones.
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