Only true for pure analog recordings.. Unless it's a high sample rate digital recording there is a brickwall at 20KHz.. Though Vinyl supports up to 50KHz for the first few plays (After that things get worn pretty quickly).

quote:

Originally posted by jahnlay The high inaudible frequencies relax the brain by creating alpha waves. That's the reason that vinyl always feels so much better than cd, vinyl can get up to 40kHz.

You bring up some good points that are very interesting; please don't think I'm picking on you or discouraging discussion, because I was actually thinking about alpha and theta waves and music's effect on them just a few days ago, and I was thinking about setting up an experiment with all of you guys here in the production forum. Unfortunately, it isn't feasible, since most hardware and most speakers range only from 20Hz - 20,000Hz, even if the vinyl or digital somehow contains sound over 25k.

But honestly, it is just conjecture at this point, and we're pretty much unsure of how these waves function and the variables that influence them. There are a lot of external factors going on in the environment and greater space-time continuum that probably play constant roles on these waves, not to mention our current psychological mindset.

Also, alpha waves are very, very low (or rather high?) energy spectrums, existing at below 20 Hz, so I'm not quite sure why sound at 40Hz would influence them?

You say that those higher frequencies would relax listeners, but honestly, it seems logical that sounds over 20Hz would very much annoy listeners subconsciously, as it all becomes a screeching dog whistle after a certain point. And how would the producer make proper melodies and such at these frequencies? It would be random garble, which would also add to the annoying-and-not-relaxing factor.

Anyway, not attacking you or saying you're dead wrong or anything like that - I'm just saying that we don't really know, and if we're using a scientific principle to promote vinyl or high frequency use, we can't use just the bits that are useful to our opinion; we have to see the facts that do exist, and understand that the entire principle is basically hearsay, though it is interesting hearsay.

We know these waves exist, and we've done experiments that assume (without eliminating outside variables, tsktsk) what they generally "might" do or how they "might" make you feel, but it's really subjective and just recording someone's brain in a machine is enough to alter the results of any such experiment.

If anything, I'd say vinyl's volatile nature and propensity for *POP* *CLICK* in the audible ranges make it a bit more obnoxious (but this isn't a vinyl vs digital debate at all, we all know each other's opinions on that one!)

Discuss.

quote:

Originally posted by jahnlay The high inaudible frequencies relax the brain by creating alpha waves. That's the reason that vinyl always feels so much better than cd, vinyl can get up to 40kHz.

Sorry but that's complete bollocks.

Google it and do some research before you so quickly write it off. All sounds create harmonics, and most natural sounds create harmonics of up to 50 or 60 kHz (Not 40Hz as you so wrongly put it). These frequencies stimulate the creation of alpha waves in the brain, which tend to help people relax, hence the reason that audiophiles use high quality turntables with speakers that can reproduce frequencies of up to 45 kHz. Maybe if you checked it out before saying it was bollocks you'd learn something!

quote:

You say that those higher frequencies would relax listeners, but honestly, it seems logical that sounds over 20Hz would very much annoy listeners subconsciously, as it all becomes a screeching dog whistle after a certain point. And how would the producer make proper melodies and such at these frequencies? It would be random garble, which would also add to the annoying-and-not-relaxing factor.

And you're basing your scientific approach on what you feel is subjectively logical? The producer doesn't need to create melodies at those higher frequencies, dumbass, the music creates it's own harmonics at these frequencies by itself (and it's above 20kHz or 20 000Hz by the way, not 20Hz). Go and listen to an orchestra some time and you might just start to hear what I'm talking about.

___________________
Layered Sounds Radio Show
Myspace
The DJ List

Last edited by jahnlay on Jun-13-2006 at 23:21

This is heading off the deepend.

quote:

Sound waves cause the tympanic membrane (eardrum) to vibrate. Humans can hear sounds waves with frequencies between 20 and 20,000 Hz. The three bones in the ear (malleus, incus, stapes) pass these vibrations on to the cochlea. The cochlea is a snail-shaped, fluid-filled structure in the inner ear. Inside the cochlea is another structure called the organ of Corti. Hair cells are located on the basilar membrane of the cochlea. The cilia (the hair) of the hair cells make contact with another membrane called the tectorial membrane. When the hair cells are excited by vibration, a nerve impulse is generated in the auditory nerve. These impulses are then sent to the brain.

In short you can't hear above the shortest cilia in your inner ear. that degrades over time as the shorter hairs die.

If you believe current thinking that the human ear acts in a digital fashion it follows Nyquist Theorum. Which in turn means that anything above half Nyquist will be perceived as a sinewave. ie any sound with a fundamental of 10KHz is a sine if you have 20Hz-20KHz hearing...

Try this simple test. Set up a signal generator pumping out a squarewave at 10KHz and compare the sound to a sine wave at the same freq. You won't be able to hear the difference as the first harmonic of the square is at 30KHz and out of even a 3 year old childs hearing range...

Same is true down the lower end of the spectrum too. You can't actually hear below 20Hz.

I did check it out. I suggest you read this. It's a placebo effect, nothing more.
And you haven't answered my question in the other thread yet.

quote:

Originally posted by jahnlay Google it and do some research before you so quickly write it off. All sounds create harmonics, and most natural sounds create harmonics of up to 50 or 60 kHz (Not 40Hz as you so wrongly put it). These frequencies stimulate the creation of alpha waves in the brain, which tend to help people relax, hence the reason that audiophiles use high quality turntables with speakers that can reproduce frequencies of up to 45 kHz. Maybe if you checked it out before saying it was bollocks you'd learn something! And you're basing your scientific approach on what you feel is subjectively logical? The producer doesn't need to create melodies at those higher frequencies, dumbass, the music creates it's own harmonics at these frequencies by itself (and it's above 20kHz or 20 000Hz by the way, not 20Hz). Go and listen to an orchestra some time and you might just start to hear what I'm talking about.

Wow.

Thanks for calling me a dumbass because your fragile emotional state can only envision the two feet in front of your metaphysical failure of a hypothesis about shit that you have no clue about. Thanks for assuming I didn't google it weeks ago, you asshat. Thanks for taking this conversation into a bitter, nasty place where small minds are left to do nothing but insult each other.

I really don't understand where all this animosity is coming from; I don't get what the deal is that you seem to think you need to attack me to defend your fragile opinions?

What is this psychosis??

I come in peace...

I dont see how the human ear can behave in a 'digital' fashion and there is no proof to outright state that it does and would be a huge problem when listening to analogue sound sources.

The nyquist value determines the maximum frequency range in digital audio before aliasing 'foldback' occurs.

To use the old spoked wheel example, if you watch a reel of film at a constant 30 fps of a spoked wheel turning, aliasing occurs as the rate at which the spokes of the wheel turn approaches the number of frames per second at which the camera is operating. When you see it on film the wheel appears to slow down, stop then start turning backwards as the rate at which the wheel turns increases beyond the rate at which the camera is able to sample it. This also happens with helicopter rotary blades too if you ever get a chance to see some footage of that.

Without going into the maths of nyquist theorum, to accurately measure the frequency of a signal 'f' in a digital recording, you need to sample it at greater than '2f'.

If you try to measure the frequency of a signal greater than 'f' with the samplerate at '2f' you will alias the signal.

i.e. with a sampling rate of 100hz the nyquist value would be 50hz. If you try to sample at 80hz you will alias at 20hz.

The point I am trying to make is that in digital audio you can pump out a high frequency square wave and you will get harmonics beyond 30khz as an aliasing image below the nyquist frequency. Thats a dead giveaway its not a 10khz sine wave.

In terms of listening to an analogue square wave at 10 khz and a sine wave at 10 khz I doubt I would be able to tell the fecking difference because as you say the first harmonic is way beyond the limit of human hearing. And you cant amplify a 10 khz square wave very much before it starts to kill your ears.

Also, everyone's hearing deteriorates at different rates so the whole 20hz to 20khz range is approximate anyway. Though as you say your hearing is best at a young age provided you dont have any ear defects at birth.

quote:

Google it and do some research before you so quickly write it off. All sounds create harmonics, and most natural sounds create harmonics of up to 50 or 60 kHz (Not 40Hz as you so wrongly put it). These frequencies stimulate the creation of alpha waves in the brain, which tend to help people relax, hence the reason that audiophiles use high quality turntables with speakers that can reproduce frequencies of up to 45 kHz. Maybe if you checked it out before saying it was bollocks you'd learn something!

There is absolutely no proof that this occurs. There is no concrete proof that harmonic content beyond the audible range of human hearing in any way stimulates synchronous electrical activity between large groups of neurons in the brain. Nobody really knows what causes that to happen.

The only connection that has been determined is that beta/alpha/theta/delta waves are associated with different patterns of electrical activity between neurons in the brain, and using an EEG it has been established that theta and delta wave patterns are associated with meditative and sleep states. Beta waves and alpha waves with waking states. Beta wave patterns with waking and alert states.

The only connection with music doesnt have any scientific basis except the experience of alot of people that seem to suggest music can help people to relax and repetitive and drone music can aid in achieving meditative states.

Last edited by Derivative on Jun-14-2006 at 02:28

who has a turntable needle that goes up to 40, 50k Hz ?

___________________
http://soundcloud.com/ed_m

quote:

Wow. Thanks for calling me a dumbass because your fragile emotional state can only envision the two feet in front of your metaphysical failure of a hypothesis about shit that you have no clue about. Thanks for assuming I didn't google it weeks ago, you asshat. Thanks for taking this conversation into a bitter, nasty place where small minds are left to do nothing but insult each other. I really don't understand where all this animosity is coming from; I don't get what the deal is that you seem to think you need to attack me to defend your fragile opinions? What is this psychosis?? I come in peace...

Oh don't take it so personally, dumbass is not that big of an insult! I wasn't attacking you, merely saying that the music creates it's own harmonics. There have been many scientific papers written on the fact that these harmonics stimulate brain activity, especially by the Fraunhoffer Institute. Maybe dig a bit deeper?

___________________
Layered Sounds Radio Show
Myspace
The DJ List

quote:

Originally posted by jahnlay Oh don't take it so personally, dumbass is not that big of an insult! I wasn't attacking you, merely saying that the music creates it's own harmonics. There have been many scientific papers written on the fact that these harmonics stimulate brain activity, especially by the Fraunhoffer Institute. Maybe dig a bit deeper?

I'm quite sure that most of the guys in this topic participated in a thread which was a while ago about this...I can say that we have dig a lot deeper...maybe it's now time to make each one his own opinion and shut up? I mean...both sides

___________________
Help me make soundtrack for my grandpa´s art exhibition:
Check out my topic about it here
Thank you!

Ummm. It doesnt cutoff after the nyquist frequency. It just aliases when you try to sample over it. You will get harmonics (not the same ones) over the nyquist frequency but as an aliased image below the nyquist frequency. They retain their exact proportion and amplitude and are otherwise correlated exactly to the original signal.

i.e. If nf = nyquist frequency the aliasing frequency (af) = (Sample rate (sr) x n) - frequency sampled over nf (fs)

That is:

af = (sr x n) - fs

It really is alot simpler than I seem to be putting it here. The example I posted a few posts up on this page explained it better than the formula does. But really the whole process is very simple. Deriving the maths behind it is more complicated and is not especially fun, unless you get a hard-on over integral calculus.

As for instruments that do not have any harmonics - A basic unmodified theremin does not as it is a simple sine wave. Any synthesizer set to play only sine has no harmonic content.

Additionally certain types of drums and membranophonic percussion instruments do not have harmonics in the strictest sense of the word but rather partials instead.

But yes, pretty much every natural acoustic instrument (and synthesized ones) have some component at practically every audible level (and adjacent inaudible frequency ranges besides). They arents harmonic and musical though.

Last edited by Derivative on Jun-15-2006 at 00:10