quote:

"As for sample rate, there has been much research that proves that there is a major difference between the human ear ability to hear test tones and upper order harmonics. Music reproduced with a minimum bandwidth out to 70kHz is capable of flooding the brain with endorphins, whereas the brain releases NONE when maximum bandwidth only goes out to 20kHz. When I was a kid listening to music really was better, emotionally that is.

This was a study done in Japan by some major audio manufacturer (like Sony or somebody) where an MRI was used to determine whether or not people could actually hear ultrasonic frequencies. Subjects were asked to A/B music with and without ultrasonics and to subjectively rate them. Subjects could NOT tell the difference, and there was no statistical correlation between their subjective ratings and ultrasonic content. However, the presence of ultrasonic components did cause a measurable effect in the MRI. Their conclusion was that we may be able to subliminally detect them, but that detection does not permeate our consciousness at all.

Of course, just as tobacco companies sponsor totally objective research, so do audio equipment manufacturers . . .

70kHz is, I think, way above what even children can hear. So nothing here would be making music sound better emotionally to children. Also, we seem to be jumping fast from MRI activity to endorphin release. If ultrasonic frequencies really do cause release of endoprhins, one would expect to see devices emitting bunches of them sold as pleasure-devices. Instead, as many schoolteachers now know, a good way to quiet down a classroom is to play high-pitched noise at the kiddies -- it annoys them, while the adult teachers can't hear it.

Since frequencies are vibrations , is it possible the MRI is simply detecting the physical effects on brain tissue of the ultrafrequency vibrations as they pass through the skull? (I have only a vague understanding of MRI's).

All:

I concur with much of what is being said, but I would add however.... The difference between 44.1k and 48k in capture frequency (thanks to the Nyquist theorum) correct me if I did the math wrong but about 1/5 of an octave. That really isn't that much relative to the position it appears in in the human listening range and the overall bandwidth of octaves we hear. Mathematically correct - I don't dispute that but I would add the following. The place where sample rate really matters (IMHO) is in stereo image. Keep in mind the human ear(s) can differentiate very minute shifts in localization at a broad range of frequencies. High sample rates reduce the effect of jitter and the introduction of 'blur' into the stereo image. Most of you know I do a lot of stereo baroque orchestra stuff (search on the Brockes Passion audio samples from last spring) and the improvements in stable image during capture and mix at high sample rates really matters. This is arguably why DSD and DXD are so popular among the classical elite in Europe right now. Neve, and others have agreed that PCM sample rates can reveal detail that is 'super aural' (Geoff Emorick is quoted as hearing a 3db bump at 54khz on a 'faulty' SSL console once) but while that might appear the benefits of super sample rates - that hardly translates to the average consumer and most folks playback gear. But to my point Stereo Image blurring can be heard with modest gear - and especially in earphones ala the iPod army that's out there.

Just my two cents about the importance of SR and the implied benefits of DSD and DXD.

-D

Found this beauty:

http://www.ocf.berkeley.edu/~ashon/audio/Ultrasonics.htm

That link really was a good find. I knew that ultrasonic components in a cymbal were significant, but I never would have guessed they would account for 40%!

You learn something new every day. I thought Gamelon was Godzilla's nemesis. Now I know better.


Edit: just finished reading the whole thing. The author seems to just accept the claim that you can greatly improve the playback of 16/44.1 Redbook CDs by resampling at 24/192. I'd have to be convinced.

Keep in mind the human ear(s) can differentiate very minute shifts in localization at a broad range of frequencies.

Indeed, I think that's closely involved. From the link in my previous post:

"A second explanation that may not necessarily have to refute the 20 kHz hearing limit entails engineering details slightly beyond the scope of this class. A well-respected high fidelity digital audio company, dCS, has published a white paper describing the engineering issues involved with reproducing high-sample rate material and standard sample rate material. Due to what is called the Gibbs phenomenon, typical sharp anti-aliasing filtering for standard 22 kHz sample rate material as is necessitated by the Nyquist theorem results in a ringing transient response. The energy contained in this transient ringing "smears" or "defocuses" the sound, impairing the ability to localise sounds.

Higher sample rates mitigate this problem. dCS produces an ultra high-end upsampler and DAC that converts standard 16 bit/44 kHz CD material to interpolated 24 bits at 192 kHz, improving the sound by all subjective audiophile criteria - air, soundstage, imaging, ease - to no end. Given that there is no real information being added to the signal, the engineering explanation dCS offers gains credibility."

[edit:] @bitflipper
Yeah, I got lucky - has a few interesting links down below as well - my weekend's GONE already

[edit2]

Hey bitflipper,

I did not know as much on the subject as you do so I wanna thank you for explaining. Also, DonM thanks for contributing on the subject as well. I wish you get well and to take care of yourself...we don't want you to leave us just yet . Thanks and take care dude!

I am recuperating from a heart attack

Please get well soon and take very good care of yourself.

We need you on this forum.

Best
John

ORIGINAL: John

I am recuperating from a heart attack

Please get well soon and take very good care of yourself.

We need you on this forum.

Best
John

What he said.

24/96, at the smell of hope of ones fingers that lies my passion I hide under a blanket. But I heep that hidden.

I am recuperating from a heart attack

Please stay strong. My father has had 3 heart attacks... Cancer, and kemo... Tripple bypass.... And we play 18 holes of golf every Tuesday morning.. Stay strong, and nothing can stop you

ORIGINAL: Jose7822

Here's another one by Shawn Micheal:

"As for sample rate, there has been much research that proves that there is a major difference between the human ear ability to hear test tones and upper order harmonics. Music reproduced with a minimum bandwidth out to 70kHz is capable of flooding the brain with endorphins, whereas the brain releases NONE when maximum bandwidth only goes out to 20kHz.

When I was a kid listening to music really was better, emotionally that is.

And what was he listening to? Vinyl with a frequency response of 16-18Khz maybe? Or maybe AM/FM Radio with a bandwidth of 15 Khz? Makes you wonder about the claims eh...


UnderTow

ORIGINAL: bitflipper

Geez, I hope this is making any sense at all. I am on medication this week, as I am recuperating from a heart attack that whacked me this past Monday night. I'm supposed to kick back and do nothing, but blathering on about digital audio is as close to doing nothing as I can manage.

Ouch! Take care man. I hope you recuperate fully!

UnderTow