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There is no point to distributing music in 24-bit/192kHz format.

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Re: There is no point to distributing music in 24-bit/192kHz format.

#141

Post by bigiain »

cmer wrote: post #49
Anechoic wrote: post #43

Earlier quoted context omitted.

For example, the human hear will hear a 30kHz frequency if it's fundamental is 10kHz You are going to have to provide me with a citation to back that up because that goes against everything I've learned and experience in 17 years of working in acoustics.

Humans will hear the impact > 20kHz frequency has on the lower frequencies, not the 30kHz frequency itself. That's been proven a million times.

If that is true, surely in your up thread example of recording a triangle, the "impact on lower then 20kHz frequencies" would already have happened during the recording process in between the triangle and the microphone, and would have been captured perfectly on recording equipment that's proven capable of capturing everything below 20kHz? So we'd "hear" the effect as part of the recording instead of requiring it to happen in our listening room…

Re: There is no point to distributing music in 24-bit/192kHz format.

#142

Post by DanBC »

Anechoic wrote: post #43
cmer wrote: post #12

Earlier quoted context omitted.

Stripping frequencies above 20kHz negates the effect on the lower frequencies since those lower frequencies are not "modified" by the higher ones. The human hear can actually hear the very high harmonics when they're combined with a lower fundamental frequency. For example, the human hear will hear a 30kHz frequency if it's fundamental is 10kHz. If it's played at 44.1kHz, the 30kHz frequency is gone and all you'll he…

For example, the human hear will hear a 30kHz frequency if it's fundamental is 10kHz You are going to have to provide me with a citation to back that up because that goes against everything I've learned and experience in 17 years of working in acoustics.

Are they talking about "beat frequency" type effects?

Re: There is no point to distributing music in 24-bit/192kHz format.

#143

Post by nullc »

yzhou wrote: post #34

A person can not hear a 22kHz tone doesn't mean he can not hear a sound that contains 22kHz components. For example, a square wave contains lots of high frequency harmonics, the more higher frequency harmonics it have, the "squarer" the square wave gets. An ideal square wave forms ideal "0" "1" states. A person's ear might not be able to hear a 22Khz sine wave tone, but he might be able to sense the steepness of "0"…

First, if you can "hear the steepness" you really can hear higher frequencies, but I assume you meant "maybe you can hear higher frequencies but not higher frequency _tones_"...

People have suggested this. It's been tested in rigorous double blind tests— involving both real music signals as well as special test tones (Linked from the article). The tests were unable to show that people could hear the ultrasonics. Moreover, there isn't any physiological basis to expect people to be able to. You can't expect a stronger result than that.

Common 48KHz audio already goes a bit beyond what adults are known to be able to hear, so you've already got some headroom for "but what if a few people hear better than anyone the researchers have been able to find!".

Re: There is no point to distributing music in 24-bit/192kHz format.

#144

Post by sjwright »

polshaw wrote: post #131
Anechoic wrote: post #121

Earlier quoted context omitted.

No, even in that case, the room can still overpower the speaker. A $200 HTIB system in a properly treated room will sound a lot better than $28,000 Wilson Watt Puppies in a bathroom for example.

Sure, but that's a rather contrived example-- most people have a fairly normal room, and the average joe would be best served by getting a good pair of speakers, and a reasonable amplifier and DAC, before worrying seriously about room acoustics.

A fairly normal room is pretty awful these days, particularly with the trend towards timber flooring and sparse furnishing.

Re: There is no point to distributing music in 24-bit/192kHz format.

#145

Post by eatmyshorts »

cmer wrote: post #4

There's a lot of scientific-sounded content in this, but unfortunately most of it couldn't be further from the truth. I'm an ex-audio engineer and studied digital and analog audio engineering; this has been debated to death over the last 15 years. Digitally recording a triangle is the best example of why 48kHz is very limiting. The distinct sound of the triangle constitutes of a high fundamental frequency, ballpark 5…

Yes, but our ears only hear 20Hz-20KHz. So, according to Nyquist theory, you can recreate the entire signal that the human ear hears by recording those sonic artifacts that result from interference between supersonic harmonics.

So while it's true that the human ear can't hear well above ~18KHz, and the interference between high order harmonics are audible, it's also true that a properly recorded signal, sampled at 44.1KHz, oversampled, and filtered, can reproduce the exact signal the human ear is capable of hearing. At least according to theory.

The human ear is capable of detecting sound pressure as well as sound intensity, and while playback of the interference between harmonics can be reproduced faithfully in the sound intensity realm, the sound pressure levels will differ, and it is theorized that people may be able to tell the difference between the two. However, as far as I am aware, nobody has been able to demonstrate this reliably in practice.

Re: There is no point to distributing music in 24-bit/192kHz format.

#146

Post by femto »

sjwright wrote: post #122
femto wrote: post #41

Earlier quoted context omitted.

Playing Devil's Advocate... The statement that frequencies above 20kHz don't matter rests upon the assumption that the ear is linear. If the ear is not linear (I don't know whether it is not not) then frequencies above 20kHz will matter, as the ear will be able to mix higher frequencies down to less than 20kHz. For example, if we have frequencies of 56kHz and 59kHz, the ear MIGHT be able to discern a difference frequ…

> the speakers will be the limiting factor > in most sound systems I disagree -- in most sound systems, the room is generally the most limiting factor. Pardon the reductio ad absurdum, but would you prefer to listen to $1,000 speakers in a dry, padded listening room, or to $100,000 speakers in a tile bathroom? Obviously the room matters; I think most people underestimate by how much.

Probably. I should have left it at "it's not the recording format" and not nominated a limiting factor.

I'd take the bathroom, given that my singing voice sounds less worse there! :-)

Re: There is no point to distributing music in 24-bit/192kHz format.

#147

Post by shard »

davesims wrote: post #95
hackermom wrote: post #39

Earlier quoted context omitted.

Same goes for 16/24 bit, however, the difference between 16 and 24 bit is actually audible No, the difference is not audible at all. At 16 bits of depth on a normal low-level audio signal (~0.3 volts), we're talking about less than 0.000005 volts per amplitude step. This difference gets lost in the THD already at the DAC in your audio output stage. Then it gets lost again in the amplifier. And again in the cable to y…

Heh, it's funny to see this late-nineties debate get re-hashed here. Also kind of fun. If it were true that there's no audible difference between 16 and 24 bit, companies like Alesis, Otari, ProTools, etc. wouldn't have spent the last 15 years ditching 16 bit like an old pair of smelly sneakers. (better metaphors welcome). Seriously, anyone who has sat down in a real listening environment for 5 minutes A/Bing 16 vs 2…

Sure, moving up from 16bit recording was an improvement, but having done engineering for a company listed above for over a decade, I can tell you that we went 24bit/192kHz because of market demand, not for any real technical reasons. We thought it was fairly unnecessary ourselves. It was also kind of an arms race with other companies, much like the megapixel arms race for digital cameras.

Re: There is no point to distributing music in 24-bit/192kHz format.

#148

Post by nullc »

sjwright wrote: post #78

I must say I get rather irritated when people spend time worrying about dubious 'tweaker' methods to improve their audio, when the most under-performing component of most people's sound equipment also has the lowest-hanging fruit: The room itself. When people ask me where they should spend money to improve the quality of their hi-fi or home theater system, in nearly every case my response will be something like "get…

Audio tweaker with hacker leanings but without carpentry skills? Start your engines: http://drc-fir.sourceforge.net/

Re: There is no point to distributing music in 24-bit/192kHz format.

#150

Post by mistercow »

> Can you see the LED flash when you press a button? No? Not even the tiniest amount?

I used to be able to see it when I was a kid (it looked very faintly red), but I just tried it and couldn't see it at all. That's actually a little bit disturbing.

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