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24/192 Music Downloads and why they make no sense (2012)

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Re: 24/192 Music Downloads and why they make no sense (2012)

#121

Post by mixmastamyk »

PascLeRasc wrote: post #9

I have a degree in electrical engineering, and I'm currently in a graduate course on computer music systems, so I hope that qualifies me enough to avoid the author's ad hominem attacks he seasons this stinkpiece with. I can't stand seeing frequency response charts and scientific measurements in articles about audio. Like my favorite audio reviewer says [1], I listen to music for enjoyment and I talk about audio in su…

There is the law of diminishing returns on audio quality, as in everything. Empirical data collection is not a thing to be avoided however.

Given that, your rant seems misplaced, and I can't help but think engineering is not the field for you.

Re: 24/192 Music Downloads and why they make no sense (2012)

#122

Post by IWeldMelons »

matwood wrote: post #111
IWeldMelons wrote: post #49

Earlier quoted context omitted.

If it was true, the entirety of hi-fi industry would not exist. I myself built a number of amplifiers and, after a certain threshold, roughly .02% THD (total harmonic distortion) at 20khz, there is a very little correlation between the THD (what is usually measured)numbers and perceived quality of the sound. Which means, while it is true that is everything could be measured, no one measures the right thing (perhaps s…

> the entirety of hi-fi industry would not exist. An industry which is known to sell an enormous amount of snake oil...

You are talking about hi end. Not hi-fi. Now do you have anything of substance to say?

Re: 24/192 Music Downloads and why they make no sense (2012)

#123

Post by blattimwind »

gugagore wrote: post #114
blattimwind wrote: post #87

Earlier quoted context omitted.

Except that audio DACs are generally oversampling; for example, an output filter for the AD1955 DAC is only needed to reach -3 dB at 100 kHz, even if you are feeding it a 48 kHz PCM signal. This allows these DACs to produce essentially zero energy in the frequency band from Nyquist cutoff of the input signal to filter cutoff.

This resampling adds some latency, right? Ideal resampling adds infinite latency---the sinc function has infinite support.

Yes, but it's not much. To stay with the example given above, group delay is less than 1 ms at 48 kHz fs, largely indepedent of oversampling factor (2-8).

Re: 24/192 Music Downloads and why they make no sense (2012)

#124

Post by vortico »

gugagore wrote: post #110
vortico wrote: post #93

Earlier quoted context omitted.

Resamplers these days take advance of our faster computers to use near-brickwall filters, like a 1024-point windowed sinc. With this, you can create a steep filter from 20-22 kHz with better than -100 dBr attenuation beyond the Nyquist frequency. This is enough to stop worrying about the aliasing caused by the bandpass filter. I've never heard of what newaccoutnas is talking about, but I guess if a high-frequency sou…

Do you know what frequency is typically for the resampling? Anything like 192kHz?

Do you mean what sample rates mixing/mastering engineers work in? They're usually 44.1 or 48 times 1, 2, or 4. Software/hardware DSP effects sometimes oversample interally up to 16x. If you're asking what the ADCs use, they usually have an analog filter circuit for each input, sample at 4 or 8x to digital, and then digitally decimate to 1x, all in one $5 ADC chip.

Re: 24/192 Music Downloads and why they make no sense (2012)

#125

Post by teilo »

PascLeRasc wrote: post #9

I have a degree in electrical engineering, and I'm currently in a graduate course on computer music systems, so I hope that qualifies me enough to avoid the author's ad hominem attacks he seasons this stinkpiece with. I can't stand seeing frequency response charts and scientific measurements in articles about audio. Like my favorite audio reviewer says [1], I listen to music for enjoyment and I talk about audio in su…

I'll just respond by quoting the article:

Why push back against 24/192? Because it's a solution to a problem that doesn't exist, a business model based on willful ignorance and scamming people. The more that pseudoscience goes unchecked in the world at large, the harder it is for truth to overcome truthiness... even if this is a small and relatively insignificant example.

Re: 24/192 Music Downloads and why they make no sense (2012)

#126

Post by IWeldMelons »

mrguyorama wrote: post #56
IWeldMelons wrote: post #49

Earlier quoted context omitted.

If it was true, the entirety of hi-fi industry would not exist. I myself built a number of amplifiers and, after a certain threshold, roughly .02% THD (total harmonic distortion) at 20khz, there is a very little correlation between the THD (what is usually measured)numbers and perceived quality of the sound. Which means, while it is true that is everything could be measured, no one measures the right thing (perhaps s…

Are you suggesting that things like healing crystals work, because the market for them exists?

You are putting words in my mouth. I am telling what I actually verified. Amplifiers with lower THD and IMD often sound worse than those with less impressive meausured parameters. Ergo, the measured parameters are not relevant. We need to find the actually important paramters and measure them.

Re: 24/192 Music Downloads and why they make no sense (2012)

#127

Post by IWeldMelons »

vortico wrote: post #93
IWeldMelons wrote: post #53

Earlier quoted context omitted.

Bingo! Exactly, Nyquist theory. But no one can make a truly good, brickwall filter at this frequency. It is much easier to make a lot less steep frequency response, whilch would start at 22 khz and would slowly go down all the way to 96 kHz. By the way, how would it damage the ears if it was thoroughly filtered?

Resamplers these days take advance of our faster computers to use near-brickwall filters, like a 1024-point windowed sinc. With this, you can create a steep filter from 20-22 kHz with better than -100 dBr attenuation beyond the Nyquist frequency. This is enough to stop worrying about the aliasing caused by the bandpass filter. I've never heard of what newaccoutnas is talking about, but I guess if a high-frequency sou…

Well, there are several things to keep in mind. 1. The sharper the frequency response the worse ringing in the phase response. 2. Human hearing is a mystery and the near ultrasonic freq may actually have some influence on the perception of the music. 3. You need to use analog filters before the ADC and after the DAC anyway, and it is so much easier to implement with a much less steep freq response, if used with higher sample rate. I mean, you sample it at 192 and the filter it down to remove anything above 96. There is no point to resample all the time up and down.

Re: 24/192 Music Downloads and why they make no sense (2012)

#128

Post by rixrax »

mruts wrote: post #4

Problem with music sounding bad doesn’t really have much to do with the distributed format: V0, V1, or 320 mp3s should sound pretty much the same compared to 16-bit flac. You can only the difference between mp3 and flac at shitty bitrates no one uses anymore (like 120). The reason why a lot of recent digital music sounds bad is because of the intentionally terrible mastering. Since everyone is listening of crappy ear…

Here is a link[0] to CD dynamic range database from where you can check how a particular mastering fares.

[0] http://dr.loudness-war.info

There are of course multitude of other factors impacting mastering quality, but as far as DR goes, this DB is a pretty good source.

Re: 24/192 Music Downloads and why they make no sense (2012)

#129

Post by jwagenet »

jlarcombe wrote: post #61
martin_a wrote: post #8

Earlier quoted context omitted.

But who is using MP3 players these days any more? I found myself to buy an iPod in... like... 2011 or so. Converted all the CDs I had to FLAC because losless was the way to go. Two or three years (let it be 5, doesn't matter) pass by, I got a better Smartphone, Spotify Premium and don't touch my 1xx GB of FLAC music anymore, because I don't want to carry around another device etc. I'm not sure but I think "owning" mu…

But aren't you worried you'll lose access to your music? I have to own it! I can't have it at the whim of multiple third parties to take down as they see fit. It's too important.

Nothing in my Spotify is rare, I can hunt it all down again. If Spotify pulls the plug then the biggest hassle will be recovering the track names of all the music in my sprawling playlists (which I should probably start backing up now). The benefit of Spotify to me is spending $10/mo on the >$10 of new music I listen to each month.

Re: 24/192 Music Downloads and why they make no sense (2012)

#130

Post by aw3c2 »

matwood wrote: post #108
jlarcombe wrote: post #61

Earlier quoted context omitted.

But aren't you worried you'll lose access to your music? I have to own it! I can't have it at the whim of multiple third parties to take down as they see fit. It's too important.

So where do you store these files that you'll never lose access? CDs? People with a room full of 8 tracks or cassettes would like to have a word. HDDs? Those fail all the time, plus any sort of natural disaster could wipe out your collection. Online backup? This seems like the only real option, but for me the risk/reward just doesn't fit. At least for now, the record companies and the service providers are both incen…

> Online backup? This seems like the only real option, but for me the risk/reward just doesn't fit.

What risk? You can privately store your music anywhere, it's completely legal to do so.

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