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24/192 music downloads make no sense

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Re: 24/192 music downloads make no sense

#101

Post by splitdisk »

klodolph wrote: post #38
splitdisk wrote: post #19

Earlier quoted context omitted.

I'm very jealous of your healthy hearing range... I now wear hearing protection, but the damage has been done. When it comes to file storage, I will take a 44.1/48K 24 bit FLAC happily, since it usually comes out to the same size as a CD-Q WAV file anyways. I see no reason why everything shouldn't be in this format, but CD's have made a serious dent in formatting standards/habits.

24bit has been shown to be excessive in actual tests, and it doesn't really pass the "bullshit test". 24 bit allows you to switch between a whisper in a library and a jet engine or shotgun blast in a single recording—yes, it would instantly damage your hearing. By comparison, 16 bit audio can "only" record a whisper in a library and a motorcycle or jackhammer. Double blind tests show that 8 bits are not enough, but 1…

It's my understanding that 24 bit audio can capture the quieter sounds in greater detail than 16 bit. So say if you EQ out a frequency range in order to "zoom in" on a much quieter range, like the motorcycle vs. whisper, you can hear the whisper in as much detail as a full CD quality recording.

For playback though, I agree that 14 bits are probably enough. Even high quality mastering tape has the equivalent of about 12 bits of dynamic range, which is fine. Many fabled analog pieces of equipment have terrible signal-noise characteristics, but are still valued for other reasons (coloration, distortion etc...)-which is all fine by me.

Re: 24/192 music downloads make no sense

#102

Post by copperx »

bitwize wrote: post #23
muraiki wrote: post #12

Earlier quoted context omitted.

Reading "compression" as both a programmer and audio-minded person made that first sentence difficult to parse at first. :) But yeah, it's obvious when I have my car stereo nearly on max to listen to classical or jazz, and then if I turn the radio and get a pop music station my ears are about to explode.

It's not just the acoustic properties of dynamic-compressed music. The compression forces music to be more simplistic, because there's less "room" for complexity. Michael Jackson's "Thriller" is a standard pop hit, engineered for chart performance and not artistic virtuosity, but it is still a rich, deep, satisfying piece of music to listen to in part because there's a whole lot of stuff going on. If you tried to cra…

No, compression doesn't force the music to be more simplistic. It enables simplistic music to sound fuller.

Anyone that has mixed 120+ tracks for a single "modern rock" song with a compressor at the end would tell you so.

Re: 24/192 music downloads make no sense

#103

Post by LeoPanthera »

pgrote wrote: post #70

So, what are the better settings for ripping songs?

I rip to FLAC, not because I think it sounds better, but simply because if some newer better codec comes along in the future that will let me compress my songs on my smartphone even smaller (Opus?) I don't want to have to get my CDs out again. I can just transcode from the FLAC files.

Re: 24/192 music downloads make no sense

#104

Post by weinzierl » 

  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 talked about but no one has ever seen one.

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.

"24/192 music downloads make no sense" seems to be a thoroughly researched and carefully written article. It explains oversampling very well, possible confusion with digital filtering (anti-aliasing or not) is out of question. But then it goes on to talk about digital anti-aliasing filters, which makes me afraid I could be wrong.

Do digital anti-aliasing filters exist?

Re: 24/192 music downloads make no sense

#105

Post by darkmighty »

tonecluster wrote: post #86
cynicalkane wrote: post #84

Earlier quoted context omitted.

Nope. Intermodulation distortion for out-of-range frequencies is inaudible. The 1hz beat you are hearing is not a 1hz sound wave, it's a 1000.5hz sound wave becoming louder and softer once per second. The comparison of a 1hz beat to a 1hz sound should be absurd on its face: you need about 20-30hz to become audible, and it's a low rumble more felt than heard. Very low frequencies sound absolutely nothing like intermod…

"...and cause inter-modulation products in the audible range." AFAIK, this is true in acoustic environments under conditions as described in the original post.

There are no inter-modulation products in the sense rplst8 expects. The interaction of waves of 1000Hz and 1001Hz doesn't produce 1Hz waves in linear media.

Even if it did produce some new frequencies through some non-linearity (which is negligible in most environments afaik), the recording equipment would capture the low frequency waves produced by those interactions. So the only question is whether there are significant non-linearities in our hearing system, and the overwhelming evidence is no again afaik.

Re: 24/192 music downloads make no sense

#106

Post by jamesfmilne »

msandford wrote: post #80
niels_olson wrote: post #61

Earlier quoted context omitted.

> higher bitdepths and sampling rates can be quite useful in mixing 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. The producer may have use for that range when editing, but the audience will never know what was -- may have been -- missed. And we're not talking about limits of reproduction. We're talk…

> 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…

Define HDR. Almost all displays people have these days are not capable of reproducing the dynamic range that most cameras can capture. Hence why we have colour grading, which is the image equivalent of audio mastering.

Re: 24/192 music downloads make no sense

#107

Post by Sharlin »

msandford wrote: post #80
niels_olson wrote: post #61

Earlier quoted context omitted.

> higher bitdepths and sampling rates can be quite useful in mixing 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. The producer may have use for that range when editing, but the audience will never know what was -- may have been -- missed. And we're not talking about limits of reproduction. We're talk…

> 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 modern sensor is capable of is not enough.

However, that's neither here nor there because the human eye is not the real bottleneck here. The media we use to display photos are. Printed photographs have approximately six stops of DR; typical monitors have eight. Modern cameras capture much more information than can be displayed, and the raw sensor data must be tone-mapped either by the camera software or in post-processing to produce a viewable image. There is a lot of latitude in deciding how to map 2^14 discrete values of input to a mere 2^8 values of output.

Re: 24/192 music downloads make no sense

#108

Post by yzhou »

fancyketchup wrote: post #97
yzhou wrote: post #58

There's a big difference in impulse response with different sample rates, any one can see it on a oscilloscope, I bet some one can hear the difference. Those who don't have a oscilloscope can see the picture here: http://i.imgur.com/wY0wzcW.png

The two pictures don't have the same vertical scaling, and it's clear that the probe is ahead of the LPF in the signal chain.

the probe is placed on the headphone jack. The difference in the vertical scaling is that 0dB DSD signal is 6dB below a 0dB PCM.

Re: 24/192 music downloads make no sense

#109

Post by PaulHoule »

It is not just headphones that are the problem, it is the speakers.

People today are often amazed when they listen to CD or turntable content through 70's era crossover speakers. Back in the 70's you'd have a stereo with 2 "speakers" that each had 3 subspeakers for a total of six speakers. The fad today is to have 5.1 sound with a single driver in each satellite, also a total of six speakers. The spatial resolution increase is good for movies, games and TV but surround sound in music is marginal. An amazing number of old "classic rock" recordings were done in quad and anything by Donald Fagan will sound pretty good w/ Dolby Pro Logic, there are some more recent Bjork recordings, but almost everything is mixed for stereo and what you loose in frequency response is not compensated by anything, except perhaps the ability to produce more volume with more speakers.

Re: 24/192 music downloads make no sense

#110

Post by donatj »

darkmighty wrote: post #100
hatsunearu wrote: post #10

The single worst thing that harms audio quality is excessive compression. It's ruining everything, I'd say. Heck, I'm sure everyone who knows their worth would agree that compression harms audio quality. Recommended reading: https://en.wikipedia.org/wiki/Loudness_war edit: compression as in dynamic range compression, not data compression like mp3 in audio

I have mixed feelings about it. But I fully agree all music should be uncompressed by default. The good thing about compression is that it allows you to save your hearing quite a bit. Some music have dramatic parts that get super loud, which can have awesome emotional response; but it does take a toll on your hearing, unless you are in a very silent environment or have fantastic headphone insulation (I have none) --…

I'm truly curious how having good isolation would help your hearing? Is the room noise a large additive?
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