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24-bit/192kHz music downloads and why they make no sense (2012)

people.xiph.org

171–180 of 274 posts

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#171

Earlier quoted context omitted.

And that's fine! I've got a flatmate who loves 320kpbs MP3s on studio monitors, I've got musician friends who swear by CD-audio and Sennheiser HD200s, and others who love how vinyl uniquely degrades over time on big speakers. The takeaway from these sorts of posts, at least in my opinion, should be two-fold: * Understand the physical limits of human senses and perceptions to help inoculate yourself against outright s…

> Understand the physical limits of human senses and perceptions to help inoculate yourself against outright scams and grifts Also understand that while there is an upper limit, we are all different within that. I can hear the difference between 128Kbps and FLAC, at least for some content, but not 256Kbps, maybe not 192. For some content (spoken word etc.), 64Kbps, sometimes less, is perfectly acceptable (to me). The…

I’ve not tried encoding my own MP3s in at least a decade, but when I was doing so, 128 kbps was instantly distinguishable to me on anything with cymbals, especially hi-hat: it loses that shimmery sound. At 192 kbps I could tell if I really, really tried, but it was so minute I didn’t really care. I was never able to reliably tell the difference between 256 and 320 kbps rips.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#172

Earlier quoted context omitted.

Mixing process often involves hundreds of tracks, and if each introduces aliasing, this can become a problem. Some engineers do swear by "the final mix is 16/44.1 so why mix at a different resolution?" mantra - that's fine too.

This is false. Aliasing is not additive in any meaningful way.

Ok dude, you obviously never recorded anything. Twelve mics on a drum kit, 60 tracks of rhythm guitars, several bass guitar layers, vocals, backing vocals, electric organ, percussions, saxophone solo. Do you think recording them at 44.1 somehow creates a shared "cloud-based" aliasing artifact that I store in S3?

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#173
post #164

Earlier quoted context omitted.

There are precisely zero 32 bit ADCs in existence. There are ADCs that will provide 32 bits per sample but that's entirely different. Current technology limits the bit depth to 18-22 bits and going beyond that you'd be very quickly recording brownian (atomic) noise anyway. The point about 32 bit float is that it is a useful format for mixing, editing and general processing, so it is widely used in digital audio tools…

I didn't say anything about DACs! I'm correcting a specific claim you made > Nobody uses 32 bit float for recording (to do so is just to capture at least 10 bits of noise, most of that being brownian); This is not true and not true for a good and important reason! One which has no bearing on the kind of DACs that exist. Modern field recorders allow gains set a 'reasonable' level that maximizes SNR for recordings but…

When I said "nobody uses 32 bit float for recording", I am referring to the result of the DA process that generates samples values used by a recorder.

Obviously, everyone and their mother uses 32 bit float as an internal sample format because of its fitness for purpose (except the folks who think they need 64 or 80 bit floating point, of course). But they are not using "32 bit floating point samples" - the samples come from an (at best) 18-22 bit integer conversion.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#174

@xiphmont also made an amazing video response to the many responses he received to this article. Using analog equipment he busts a bunch of myths and demonstrates what really happens with digital audio. https://video.xiph.org/vid2.shtml or on YT if you can't play it https://www.youtube.com/watch?v=cIQ9IXSUzuM

Thank you for posting this. I thought I knew a bit about what was going on with audio sampling and reproduction, but I learned a surprising amount from this well presented introduction

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#175

Earlier quoted context omitted.

There are precisely zero 32 bit ADCs in existence. There are ADCs that will provide 32 bits per sample but that's entirely different. Current technology limits the bit depth to 18-22 bits and going beyond that you'd be very quickly recording brownian (atomic) noise anyway. The point about 32 bit float is that it is a useful format for mixing, editing and general processing, so it is widely used in digital audio tools…

Why are you obsessed with DAC? Its the ADC that is WHY we capture 32/192.

If I said DAC, it was a mistyping. I am (in this context) always talking about the ADC.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#176
24-bit was created because microphone want to record large dynamic range without gain switching circuit.

96kHz was created to better reproduce 20kHz high frequency, so the digital noise shaping filter does not need to be super sharp right at the Nyquist frequency.

Both were introduced for a sound technical reason. beyond that, most are marketing non-sense to cheat consumers.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#177

Earlier quoted context omitted.

Decades ago, I was treated to an ABX test in my brother's recording studio. I easily recognized and preferred a 24/192 master he played versus the 16/44.1 down-mix. I honestly don't know whether there was something wrong with the down-mix, but qualitatively it did feel like it was "muffled" and coming from speakers, while the master really felt like live performance. He was surprised that I could tell them apart. I a…

Even for PC, I recommend some cheap studio monitors.

https://www.bhphotovideo.com/c/product/964752-REG/yamaha_hs8...

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#178

Earlier quoted context omitted.

This is false. Aliasing is not additive in any meaningful way.

Ok dude, you obviously never recorded anything. Twelve mics on a drum kit, 60 tracks of rhythm guitars, several bass guitar layers, vocals, backing vocals, electric organ, percussions, saxophone solo. Do you think recording them at 44.1 somehow creates a shared "cloud-based" aliasing artifact that I store in S3?

> Ok dude, you obviously never recorded anything.

https://ardour.org/ is my website.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#179

Earlier quoted context omitted.

Rode NT1-A 5th gen microphone claims 32-bit float output, insisting it will not clip peaks so maybe they do sample at 24 bit at a well chosen gain level and then convert to 32 bit float, with the max 24 bit value being above 1.0 float or as GP said, use two separate ADCs at two different gains and combine their output

> Rode NT1-A 5th gen microphone claims 32-bit float output, insisting it will not clip peaks Of course it does! And that's what it does, of course. But that has absolutely nothing to do with the AD process itself, which is chip-limited to 24 bits and likely physics-limited to somewhat less than that. You can't beat the physical limit of a DA circuit by doubling them up at different gains. And .. you don't want to. Go…

you have 22 bits for the typical audio voltage level, which you call 1.0 float

but what if you "allow" double that voltage and call it 2.0 float? a strong pressure into the microphone generates a stronger voltage

thermal noise limits you on the quiet signals, but not on the powerfull ones

so 22 bit for typical -1.0 -> 1.0 range and you can add a few more bits on top of that for stronger audio pressures (voltages) which you would traditionally clip

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#180

Earlier quoted context omitted.

Dude I've been doing sound design on films using these techniques for years. There is zero 'woo' involved, it is ALL practical evidence based use. I've been using 32bit float multitrack field recorder by Sound Devices MixPre10-II professionally for many years now. The recorder has three preamps per mic input, each gain staged to provide optimum signal to the 32bit float AD. Read this to clarify your thinking: https:/…

> I am talking about an industruy you have no knowledge or lived experience with I'm the original/lead developer of Ardour, a cross-platform DAW, and have been working with digital audio for more than 25 years. There are no 32 bit ADCs - your SD MixPre's are giving you (at best) 22 bits packaged as a 32 bit float value. The preamps make absolutely zero difference to the AD conversion (though they might sound real nic…

I do not use the DACs in the MixPre. Its a recording device. The field recordings & studio recordings are transferred as data and used in a 32bit float 192kHz Protools session. So the recorders DAC is completely irrelevant. The sounds are then used as source material, for processing and manipulation at 192k, 96k and 48k. There is no debate to be had. This is how film sound designers work & have worked for years now.

The half speed you call naive is again just showing your ignorance. Sound editors have been using this technique since the days of recording on a Nagra at 15ips and literally replaying at 7.5ips half speed, and at 3.75ips for quarter speed. There is nothing naive about it, it is a very well know technique. To be able to achieve the same result digitally with full spectrum has impacted every feature film you have experienced in recent years. Again I speak from decades of lived experience.

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