If you haven't read any of the previous articles, you might want to have a look at some of that stuff, as it gives you the basic building blocks for putting together a binaural preset using an audio editor.
Just to quickly summarize - you create two audible tones, one in each ear. The tones should ideally be between 200 HZ to 1000 HZ, and the difference between the tones is the binaural beat you are gunning for.
So, if you want an 5 HZ binaural (associated with sleep), you would put a 200 HZ tone in the left ear, and a 205 HZ tone in the right.
Ideally, the end result should be listened to with headphones, if you want a real binaural. If you listen through speakers, you'll get a monaural beat instead of a binaural beat. (Although, I find monaural beats work very well also.)
---
Now, on to the topic of today's blog -- RAMPING.
Say you want to create a binaural preset to help you fall asleep. You would just do what I described above. 5 HZ binaural -- 200 HZ left ear, 205 HZ right ear. Voila - done.
If you are already kind of/sort of sleepy, or at least relaxed - this will work fine.
However, let's say you've just come from Starbucks (or for New Englanders, Dunkin Donuts), and you've just consumed a dozen large coffees.
Or -- let's say you've just spent the last 12 hours playing Call Of Duty, and are in such an insane state of hyper-vigilance that sleep seems like an impossibility at this point.
In that case - you might need to ramp down to the brainwave frequencies associated with sleep, rather than just starting off with a 5 HZ binaural. You need to coax your brain down from where it currently is, down into dreamland.
To do this, you start with a higher binaural, closer to your mental state. So, you may want to start at 20 HZ. From there, over time, you gradually drop the binaural down to 5 HZ. The bigger the difference, the longer you want to make the rampdown.
The easiest way to do this. With an audio editor, set one ear to a consistent tone. In keeping with what we used above, let's set the left ear to 200 HZ. You want to make this a fairly long duration. For this example, let's do 20 minutes worth of it (1200 seconds).
Now, for the right ear, we're going create an audible tone that effectively creates a 20 HZ binaural, and then gradually works it's way down to a 5 HZ binaural. With Adobe Audition, the tone generator allows you to set an initial value and a final value - it allows you to limit it to either the left or right channel, and then mix paste the end result in with the left channel tone you already created. The initial value should be 220 HZ, and the final value should be 205 HZ. (This, paired up with the 200 HZ tone in the left ear will create the binaural beats we're looking for.)
One thing to note - since this is a fairly long file, and since we're not creating a background sound to pair up with the tone, it doesn't hurt to keep the sample rate very low. I've been testing with sample rates as low as 8000 HZ and 16 bit resolution, and I haven't noticed any degradation at all, particularly using sine waves.
Now, if you incorporate the background sound (noise, nature sounds) right into the main audio file, then you'll need to go higher with the sample rate to accurately capture the higher frequencies from the background sound. However, the binaural itself is not going to have much in terms of higher frequencies, so lower sample rates are fine here. (At worst, if you're using waveforms that have overtones, you might cut off some of the highest overtones.)
As I promised last time, I am linking to a couple of examples. One ramps down from the alpha range into delta. A second example ramps up, from the Alpha-Theta line up into higher Beta.
Disclaimer #1 - depending on the web-based plugin your browser is using, these WAV files may or may not work within the browser. You might have to download the WAV and then open it locally from your computer.
Disclaimer #2 - you might want to push down the volume you a little on your speakers when initially playing, and then adjust to a comfortable level. The first example at least is recorded a little 'hot' in terms of the levels.
Disclaimer #3 - should whatever device you play the sound from implode or spontaneously combust, I will not be held liable, as it was clearly either a manufacturer defect of some kind, or you didn't lower the volume like I suggested above. =)
Example of downward ramping : Alpha to Delta
https://drive.google.com/file/d/0BzTirQgov1pmOEl5bktFTE9yS2c/view?usp=sharing
Example of upward ramping : Alpha to Beta
https://drive.google.com/file/d/0BzTirQgov1pmaWx5elRCZkwxQUE/view?usp=sharing
Example of Mike rapping
(Nah - I don't think the world is ready for that.)
Sunday, October 11, 2015
Saturday, September 12, 2015
The Anatomy Of A Binaural Beat Soundscape Pt. 2
If you haven't read Pt. 1 of this blog, I would start there. It delves into the core tones that make up binaural beats.
I've been procrastinating writing part two, since it involves the background sound(s) often paired up with binaural beats, and there is a LOT of subjectivity here.
You have the raw audible tones that carry the binaural beat, and frankly - these can be fairly monotonous to listen to by themselves. (It's like drinking black coffee -- some people can get into it, but other people need the cream and sugar to make things palatable.)
Normally the binaural sound is paired up with a background sound, to keep things 'interesting'.The background sound can be anything, and it's typically left to the personal taste of the individual.
Background Sound Categories
I Nature Sounds / Environmental Recordings
This is exactly what it says on the proverbial tin. Insert any number of different nature sounds here. Oceans, Rainfall, Rivers, Wind, etc. I'd also extend this category to include environmental recordings (not all of which really qualify as 'nature'.) For instance, some people may play the sounds of the city in the background.
II Noise
Raw noise, which comes in various flavors :
Noise can be generated by computer - in its purest form, it's pretty uniform/non-changing. This may be what you're looking for. However, some people may get bored with this - any number of effects can be added over the noise to change it up a little and/or make it more dynamic over time. (For instance, reverb or flanger, etc.)
Another source of 'unboring' noise involves tuning a radio to a frequency without a dominant signal. I find shortwave radio works particularly well for this. The noise generated tends to be very dynamic in that it can change considerably over time. When initially tuning to a frequency, you may have fairly 'clean' noise, but I find distant radio signals will sometimes 'wander' onto the frequency as atmospheric conditions change, and then leave every bit as quickly as they appeared. (If you're interested in what causes this phenomena, Google 'Skywave' or 'Shortwave Skip' for more information.)
Why is noise effective as a background?
One reason may be the Ganzfeld Effect, which states if the brain is presented with nothing but featureless/uniform/random sensory input to chew on, it can lead to hallucination, as it tries to fill the garbage input with something more relevant.
An example of the conditions that would create this effect : Somebody exploring the South Pole in blizzard conditions -- they would see nothing but white no matter where they looked. Noise kind of functions as an audio equivalent to this.
III Music
Naturally, music is often used as a background sound for binaural beats. It's not uncommon for somebody to have the naked binaural sound playing, and then play a music album in conjunction with it.
One thing to note is the sort of music selected will obviously in itself have an impact on the brainwave entrainment. (The tempo of the beat can entrain the brain by itself.) So, if you are playing binaurals intended to induce sleep, and you pair that up with faster trance or death metal, it's probably going to counteract the effect.
I find simpler, more mellow music tends to work better as a background - optimally, you need to leave enough 'frequency space' for the binaurals to shine through in the mix. If you do plan on using music that is more 'intense', you really need to regulate the volume relative to the binaural. This is especially true if you're generating the music from the same headphones you're generating the binaurals. If you're listening to the binaurals through headphones, and have some other device playing the music, I think you have more wiggle room in this regard, since the music is at a distance from you, and would be more hushed/muted as a result.
IV ASMR
This is a newer one, and I'm honestly still finding ways of getting it to play nice with binaural beats.
It stands for Autonomous Sensory Meridian Response, and the premise is that certain sounds will cause a tingling sensation down the spine in some people.
If you want a crash course on what ASMR's are, just type it into Youtube, and you'll have plenty of [interestingly bizarre] examples.
Normally, ASMR recordings make use of binaural-recording techniques. (Again, binaural-recording is different from binaural beats - it's a method of recording that tries to accurately replicate how humans take in sound from both sounds.) The end result is vivid 3D -- it will literally feel as though the source of the sound is in the room with you and circling around.
Other factors that contribute to the ASMR-response involve a lot of whispering and other sounds that involve ultra-high frequencies.
If you aim to incorporate an ASMR recording right into the same audio file with the binaural beat, you want to make sure that you are setting the sample rate fairly high (to at least 44100) - this way you're not cutting out any of the higher frequencies.
One other thing to note is that like binaural beats, ASMR recordings typically require headphones - you can get some of the ASMR effect through two well-placed speakers on opposing sides, but I find headphones work the best.
One thing I find is that ASMR's and binaurals don't always get along with each other. Based on what limited testing I've done, it seems like the binaural tone constantly playing mucks a bit with the ASMR sounds. I'm thinking sidechain compression may assist with this.
To keep things nontechnical, sidechain compression basically tells one sound to get the [bleep] out of the way when another sound is present. Depending on how high you set it, it may mute the other sound outright, or at very least it will diminish it somewhat. (You'll often hear this used on commercial radio -- the background music is set to drop in volume when the DJ is talking. If the timing is done well, you'll hardly notice it.)
So, you could set the binaural tone to clear out when any sounds are present from the ASMR recording.
V Guided Meditation / Hypnosis
I'm not going to dwell on this one too much, but it's worth mentioning. Some people will use guided meditation and/or hypnosis recordings as the background sounds. This particularly works well with binaural beats in the Alpha and Theta range.
This is exactly what you think it is - somebody talking with the 'imagine you are in a forest/field/path/beach' sort of dialogue. You'll often also hear the classic 'when I count back from 10 to 1, you'll fall into a deep sleep' line.
While it seems like I poke fun at it above, I do find these guided meditation dialogues to be very effective -- they've helped me fall asleep (or at least relax) more than once when I've been stressed out over something.
Like with most of these categories, you can find examples over on Youtube.
VI 'Other'
Again, I'm just barely scratching the surface here. If you go to Youtube, you will find all sorts of videos that can potentially be used as background sounds for binaurals. A lot of these sounds run for an extended period time. [Hours]
For instance, you will find a Youtube video with an extended play of the sound of ANY appliance you can think of.
Literally - ANYTHING. Fans, hairdryers, washing machines, air-conditioners - you name it.
If you read through the comments section, it becomes immediately clear how much of this boils down to taste.
Take hairdryers, for example - people seem to either love or hate their sound. For me, the sound of a hairdryer will put me to sleep in a hurry. Obviously, an audio recording of a hairdryer is far less of a fire hazard (and power drain) than literally running one while you sleep.
---
Disclaimer : While it may seem otherwise above, Youtube does not send me my weight in internet money every time I name drop them here. It just so happens they're a treasure trove (or garbage dump?) of all the different sounds in the world.
Next Blog : Hopefully I can provide some legitimate audio examples of binaural beats. I found a place that I can store the files, and am just working out the logistics now.
Also, I'm going to let you know how to protect yourself when an army of angry mimes attacks you.
(Hint : You need to trap them in a giant invisible box.)
I've been procrastinating writing part two, since it involves the background sound(s) often paired up with binaural beats, and there is a LOT of subjectivity here.
You have the raw audible tones that carry the binaural beat, and frankly - these can be fairly monotonous to listen to by themselves. (It's like drinking black coffee -- some people can get into it, but other people need the cream and sugar to make things palatable.)
Normally the binaural sound is paired up with a background sound, to keep things 'interesting'.The background sound can be anything, and it's typically left to the personal taste of the individual.
Background Sound Categories
I Nature Sounds / Environmental Recordings
This is exactly what it says on the proverbial tin. Insert any number of different nature sounds here. Oceans, Rainfall, Rivers, Wind, etc. I'd also extend this category to include environmental recordings (not all of which really qualify as 'nature'.) For instance, some people may play the sounds of the city in the background.
II Noise
Raw noise, which comes in various flavors :
- White Noise : With white noise, the frequencies are evenly distributed. Examples of white noise - 'clean' television static [without any signal interfering].
- Pink Noise : Sometimes also called 'tan noise'. Pink noise has the frequencies distributed by octave -- because there are more octaves in lower frequency ranges, pink noise sounds 'lower' than white noise, and is bit more harmonious sounding overall.
- Brown Noise : Without getting overly mathematical, brown noise favors lower frequencies even more than pink noise does, and can sound like a lower-pitched babbling brook.
Noise can be generated by computer - in its purest form, it's pretty uniform/non-changing. This may be what you're looking for. However, some people may get bored with this - any number of effects can be added over the noise to change it up a little and/or make it more dynamic over time. (For instance, reverb or flanger, etc.)
Another source of 'unboring' noise involves tuning a radio to a frequency without a dominant signal. I find shortwave radio works particularly well for this. The noise generated tends to be very dynamic in that it can change considerably over time. When initially tuning to a frequency, you may have fairly 'clean' noise, but I find distant radio signals will sometimes 'wander' onto the frequency as atmospheric conditions change, and then leave every bit as quickly as they appeared. (If you're interested in what causes this phenomena, Google 'Skywave' or 'Shortwave Skip' for more information.)
Why is noise effective as a background?
One reason may be the Ganzfeld Effect, which states if the brain is presented with nothing but featureless/uniform/random sensory input to chew on, it can lead to hallucination, as it tries to fill the garbage input with something more relevant.
An example of the conditions that would create this effect : Somebody exploring the South Pole in blizzard conditions -- they would see nothing but white no matter where they looked. Noise kind of functions as an audio equivalent to this.
III Music
Naturally, music is often used as a background sound for binaural beats. It's not uncommon for somebody to have the naked binaural sound playing, and then play a music album in conjunction with it.
One thing to note is the sort of music selected will obviously in itself have an impact on the brainwave entrainment. (The tempo of the beat can entrain the brain by itself.) So, if you are playing binaurals intended to induce sleep, and you pair that up with faster trance or death metal, it's probably going to counteract the effect.
I find simpler, more mellow music tends to work better as a background - optimally, you need to leave enough 'frequency space' for the binaurals to shine through in the mix. If you do plan on using music that is more 'intense', you really need to regulate the volume relative to the binaural. This is especially true if you're generating the music from the same headphones you're generating the binaurals. If you're listening to the binaurals through headphones, and have some other device playing the music, I think you have more wiggle room in this regard, since the music is at a distance from you, and would be more hushed/muted as a result.
IV ASMR
This is a newer one, and I'm honestly still finding ways of getting it to play nice with binaural beats.
It stands for Autonomous Sensory Meridian Response, and the premise is that certain sounds will cause a tingling sensation down the spine in some people.
If you want a crash course on what ASMR's are, just type it into Youtube, and you'll have plenty of [interestingly bizarre] examples.
Normally, ASMR recordings make use of binaural-recording techniques. (Again, binaural-recording is different from binaural beats - it's a method of recording that tries to accurately replicate how humans take in sound from both sounds.) The end result is vivid 3D -- it will literally feel as though the source of the sound is in the room with you and circling around.
Other factors that contribute to the ASMR-response involve a lot of whispering and other sounds that involve ultra-high frequencies.
If you aim to incorporate an ASMR recording right into the same audio file with the binaural beat, you want to make sure that you are setting the sample rate fairly high (to at least 44100) - this way you're not cutting out any of the higher frequencies.
One other thing to note is that like binaural beats, ASMR recordings typically require headphones - you can get some of the ASMR effect through two well-placed speakers on opposing sides, but I find headphones work the best.
One thing I find is that ASMR's and binaurals don't always get along with each other. Based on what limited testing I've done, it seems like the binaural tone constantly playing mucks a bit with the ASMR sounds. I'm thinking sidechain compression may assist with this.
To keep things nontechnical, sidechain compression basically tells one sound to get the [bleep] out of the way when another sound is present. Depending on how high you set it, it may mute the other sound outright, or at very least it will diminish it somewhat. (You'll often hear this used on commercial radio -- the background music is set to drop in volume when the DJ is talking. If the timing is done well, you'll hardly notice it.)
So, you could set the binaural tone to clear out when any sounds are present from the ASMR recording.
V Guided Meditation / Hypnosis
I'm not going to dwell on this one too much, but it's worth mentioning. Some people will use guided meditation and/or hypnosis recordings as the background sounds. This particularly works well with binaural beats in the Alpha and Theta range.
This is exactly what you think it is - somebody talking with the 'imagine you are in a forest/field/path/beach' sort of dialogue. You'll often also hear the classic 'when I count back from 10 to 1, you'll fall into a deep sleep' line.
While it seems like I poke fun at it above, I do find these guided meditation dialogues to be very effective -- they've helped me fall asleep (or at least relax) more than once when I've been stressed out over something.
Like with most of these categories, you can find examples over on Youtube.
VI 'Other'
Again, I'm just barely scratching the surface here. If you go to Youtube, you will find all sorts of videos that can potentially be used as background sounds for binaurals. A lot of these sounds run for an extended period time. [Hours]
For instance, you will find a Youtube video with an extended play of the sound of ANY appliance you can think of.
Literally - ANYTHING. Fans, hairdryers, washing machines, air-conditioners - you name it.
If you read through the comments section, it becomes immediately clear how much of this boils down to taste.
Take hairdryers, for example - people seem to either love or hate their sound. For me, the sound of a hairdryer will put me to sleep in a hurry. Obviously, an audio recording of a hairdryer is far less of a fire hazard (and power drain) than literally running one while you sleep.
---
Disclaimer : While it may seem otherwise above, Youtube does not send me my weight in internet money every time I name drop them here. It just so happens they're a treasure trove (or garbage dump?) of all the different sounds in the world.
Next Blog : Hopefully I can provide some legitimate audio examples of binaural beats. I found a place that I can store the files, and am just working out the logistics now.
Also, I'm going to let you know how to protect yourself when an army of angry mimes attacks you.
(Hint : You need to trap them in a giant invisible box.)
Friday, August 21, 2015
The Anatomy Of A Binaural Beat Soundscape Pt. 1
Now that we have gotten past some of the most basic forms of entrainment, I want to go over the anatomy of a basic tone containing a binaural beat.
This can be created using mostly any audio editor application. I've typically used Adobe Audition, but feel free to comb this list for other freeware alternatives :
http://open-tube.com/20-free-digital-audio-editors/
Before we go any further, it's time for the 'Standard Disclaimer/Warning' :
I would tread carefully in downloading any of these audio editors. Many of these sites use download mirrors like CNET and Softpedia, so it goes without saying to thoroughly virus-check anything you download before installing it.
Also - always make sure you are selecting the right 'Download' button. A lot of these sites have banner advertisements that try and trick you into thinking their 'Download' button is the real one.
(CNET in particular worries me - it always seems to set off the virus alerts built into the Firefox browser I'm using.)
Okay, now that I have told you everything you already know about the nature of the Internet, let's get back to the topic at hand :
So, let's say you want to make a sound file containing binaural beats to help you sleep. What should it contain?
The Audible Tones
Obviously, the most critical piece of the puzzle is the two audible tones that create the binaural beat. So let's say we want to aim for a binaural beat associated with 5 HZ (which would be associated with sleep). Like I had written in the previous entry, you're going to do two audible tones, one in each ear. The two audible tones should subtract out to 5 HZ.
How do we decide what exact audible tones to use? :
Pitch
While there is some debate over this, a common thought is that binaural beats will not work using audible tones over 1000 HZ. For that reason, you want to aim below that.
There is also a lower cutoff for the audible tones. You don't want to venture too far below 200 HZ with them.
There are a couple reasons for this -- for starters, the tones tend to get more bassy, and this is a mixed blessing for binaurals beats :
On one hand, if you want to smuggle the audible tones containing the binaural beats into music, what better place to hide them than in the bass range, since the human ear is less sensitive to that range?
On the other hand, does the lack of sensitivity humans have to the bass range make the binaurals less effective as a result? One would probably have to boost up the volume on the bass to compensate for this, which leads to the next potential issue.
When trying to incorporate binaural beats into music, generally the lower in audible tone you go, the more impact adding in the binaural is going to have on the perceived note, since there is less space [in HZ] between notes in lower octaves.
On top of all that, there is yet another reason why audible tones in the bass range can sometimes be bad for constructing binaurals, and it involves something we all hate -- math. (Okay everybody, get out your calculators.)
Given the two audible tones you are using to construct a binaural. Take the lesser of those two numbers and multiply that by 16%. That value is the maximum binaural beat that can be created by these audible tones.
For example, say you wanted to use audible tones around 100 HZ to create a binaural. The maximum binaural value that could be supported would be 100 HZ x 16 %, or 16 HZ.
As you can see -- a 200 HZ tone is going to be able to cover most of the gamut of brainwave frequency ranges. (It would be able to accommodate binaurals up 32 HZ, and more often than not, that's as high as you'll need to go.)
Once you start going below 200 HZ (and particularly below 100 HZ), you're starting to limit the binaural beat playing field a little.
Waveform
I believe it has been said that the triangle waveform is best to use for the audible tones comprising binaurals. (I can't remember the exact reason why.) I find I usually stick with sine waves or triangle waves, and use square and sawtooth waves less frequently.
Volume [Amplitude]
I'm calling it volume, even though amplitude is probably the more accurate name. The volume of the audible tones should be comfortable to listen to. Generally, the higher up you go towards 1000 HZ, the less overall volume you need for the tone, since the ear gets more sensitive to sound as you head up that way. If you're using a background sound, it's perfectly okay to let the background sound take the lead volume-wise, while putting the audible tones containing the binaural a bit further in the background.
Panning
I wouldn't do any panning with the audible tones containing the binaural. The short answer is it will probably mess with the binaural functioning.
The long answer is there are probably ways you can incorporate panning into the audible tones that comprise the binaural beat, but it's not an exact science. If you were to have the left and right channels trade places X times a second, at slower panning speeds I'm thinking you'd get something that alternated between a binaural and monaural. At faster panning speeds, you would end up with a monaural, I would think - since the brain would effectively perceive both tones as being in both ears. The more I think about this, the more I want to experiment with this -- the frequency of the panning between the left and right ear itself would have a brainwave entrainment effect itself. It would be interesting to see how the brainwave entrainment effect caused by the binaural interacted with the brainwave entrainment created by the panning itself. If the binaural beat was 7 HZ and the frequency
of the panning was 6 HZ, you might end up with an almost polyrhythmic sort of effect.
Sample Rate
This is getting a little more technical.
Just to give a definition of Sample Rate from WhatIs.Com :
"In developing an audio sound for computers or telecommunication, the sample rate is the number of samples of a sound that are taken per second to represent the event digitally."
Now, it's time for math :
The sample rate of the audio file needs to be at least twice as much as the highest frequency you wish to hear in the sound. For instance, if you want to hear frequencies in a sound in the 4000 HZ range, you're going to need at least an 8000 HZ sample rate.
On the other side of the coin, generally the bigger the sample rate is, the bigger the file size will be.
For binaural beats, since the audible tones comprising the beats will be under 1000 HZ, you should be able to save the file with an extremely small sample rate, which results in a very small file size. I have tested binaurals I've created with sample rates as low as 6000 HZ, and have still been able to perceive the brainwave entrainment effect. (Just to put the 6000 HZ sample rate in perspective, audio from a music CD typically has a 44100 sample rate, and DVD audio can be even higher than that.)
Now, the downside of using low sample rates with binaural beats :
That will be 'Pt 2', since I'm getting carpal tunnel here. If I do any more typing tonight, I think my fingers will unionize and go on strike. (Although, a horde of striking finger puppets is admittedly an entertaining thought.)
This can be created using mostly any audio editor application. I've typically used Adobe Audition, but feel free to comb this list for other freeware alternatives :
http://open-tube.com/20-free-digital-audio-editors/
Before we go any further, it's time for the 'Standard Disclaimer/Warning' :
I would tread carefully in downloading any of these audio editors. Many of these sites use download mirrors like CNET and Softpedia, so it goes without saying to thoroughly virus-check anything you download before installing it.
Also - always make sure you are selecting the right 'Download' button. A lot of these sites have banner advertisements that try and trick you into thinking their 'Download' button is the real one.
(CNET in particular worries me - it always seems to set off the virus alerts built into the Firefox browser I'm using.)
Okay, now that I have told you everything you already know about the nature of the Internet, let's get back to the topic at hand :
So, let's say you want to make a sound file containing binaural beats to help you sleep. What should it contain?
The Audible Tones
Obviously, the most critical piece of the puzzle is the two audible tones that create the binaural beat. So let's say we want to aim for a binaural beat associated with 5 HZ (which would be associated with sleep). Like I had written in the previous entry, you're going to do two audible tones, one in each ear. The two audible tones should subtract out to 5 HZ.
How do we decide what exact audible tones to use? :
Pitch
While there is some debate over this, a common thought is that binaural beats will not work using audible tones over 1000 HZ. For that reason, you want to aim below that.
There is also a lower cutoff for the audible tones. You don't want to venture too far below 200 HZ with them.
There are a couple reasons for this -- for starters, the tones tend to get more bassy, and this is a mixed blessing for binaurals beats :
On one hand, if you want to smuggle the audible tones containing the binaural beats into music, what better place to hide them than in the bass range, since the human ear is less sensitive to that range?
On the other hand, does the lack of sensitivity humans have to the bass range make the binaurals less effective as a result? One would probably have to boost up the volume on the bass to compensate for this, which leads to the next potential issue.
When trying to incorporate binaural beats into music, generally the lower in audible tone you go, the more impact adding in the binaural is going to have on the perceived note, since there is less space [in HZ] between notes in lower octaves.
On top of all that, there is yet another reason why audible tones in the bass range can sometimes be bad for constructing binaurals, and it involves something we all hate -- math. (Okay everybody, get out your calculators.)
Given the two audible tones you are using to construct a binaural. Take the lesser of those two numbers and multiply that by 16%. That value is the maximum binaural beat that can be created by these audible tones.
For example, say you wanted to use audible tones around 100 HZ to create a binaural. The maximum binaural value that could be supported would be 100 HZ x 16 %, or 16 HZ.
As you can see -- a 200 HZ tone is going to be able to cover most of the gamut of brainwave frequency ranges. (It would be able to accommodate binaurals up 32 HZ, and more often than not, that's as high as you'll need to go.)
Once you start going below 200 HZ (and particularly below 100 HZ), you're starting to limit the binaural beat playing field a little.
Waveform
I believe it has been said that the triangle waveform is best to use for the audible tones comprising binaurals. (I can't remember the exact reason why.) I find I usually stick with sine waves or triangle waves, and use square and sawtooth waves less frequently.
Volume [Amplitude]
I'm calling it volume, even though amplitude is probably the more accurate name. The volume of the audible tones should be comfortable to listen to. Generally, the higher up you go towards 1000 HZ, the less overall volume you need for the tone, since the ear gets more sensitive to sound as you head up that way. If you're using a background sound, it's perfectly okay to let the background sound take the lead volume-wise, while putting the audible tones containing the binaural a bit further in the background.
Panning
I wouldn't do any panning with the audible tones containing the binaural. The short answer is it will probably mess with the binaural functioning.
The long answer is there are probably ways you can incorporate panning into the audible tones that comprise the binaural beat, but it's not an exact science. If you were to have the left and right channels trade places X times a second, at slower panning speeds I'm thinking you'd get something that alternated between a binaural and monaural. At faster panning speeds, you would end up with a monaural, I would think - since the brain would effectively perceive both tones as being in both ears. The more I think about this, the more I want to experiment with this -- the frequency of the panning between the left and right ear itself would have a brainwave entrainment effect itself. It would be interesting to see how the brainwave entrainment effect caused by the binaural interacted with the brainwave entrainment created by the panning itself. If the binaural beat was 7 HZ and the frequency
of the panning was 6 HZ, you might end up with an almost polyrhythmic sort of effect.
Sample Rate
This is getting a little more technical.
Just to give a definition of Sample Rate from WhatIs.Com :
"In developing an audio sound for computers or telecommunication, the sample rate is the number of samples of a sound that are taken per second to represent the event digitally."
Now, it's time for math :
The sample rate of the audio file needs to be at least twice as much as the highest frequency you wish to hear in the sound. For instance, if you want to hear frequencies in a sound in the 4000 HZ range, you're going to need at least an 8000 HZ sample rate.
On the other side of the coin, generally the bigger the sample rate is, the bigger the file size will be.
For binaural beats, since the audible tones comprising the beats will be under 1000 HZ, you should be able to save the file with an extremely small sample rate, which results in a very small file size. I have tested binaurals I've created with sample rates as low as 6000 HZ, and have still been able to perceive the brainwave entrainment effect. (Just to put the 6000 HZ sample rate in perspective, audio from a music CD typically has a 44100 sample rate, and DVD audio can be even higher than that.)
Now, the downside of using low sample rates with binaural beats :
- If you're using more elaborate waveforms with harmonic overtones, you may end up cutting out some of those overtones.
- You're generally not going to create a binaural beat in a vacuum, because naked binaural tones are boring. People need something acoustic to chew on, so you typically will add a background sound of some kind (ocean waves, noise, etc). These sounds will have higher frequencies, and will warrant a higher sample rate.
That will be 'Pt 2', since I'm getting carpal tunnel here. If I do any more typing tonight, I think my fingers will unionize and go on strike. (Although, a horde of striking finger puppets is admittedly an entertaining thought.)
Sunday, August 16, 2015
Brainwave Entrainment : Some basic types
I'm going to go over some of the more common methods/sources of brainwave entrainment here. This list isn't exhaustive. I'm really just scratching the surface.
I welcome any feedback you may want to offer - I don't know everything, so if you think I am botching up some detail below, feel free to call me on it in the comments section.
Additionally, if you think there are better ways for me to present this information, let me know.
I Visual Entrainment :
Lights flickering X times per second can be used to entrain in the brain into various mental states. Point in case - a strobe light flashing 20 times a second can be used to energize a crowd of people.
A variation on this theme - if one watches something moving/oscillating X times a second, this can also potentially be used to entrain the brain. (Example : A hypnotist swinging a timepiece or some other object on a chain to put somebody into a trance.)
II Motion Entrainment :
Any periodic motion a person experiences can also have brainwave entrainment effects.
Examples : A rocking chair, swinging on a swing, a mother gentling rocking a child in her hands, etc.
III Electromagnetic Entrainment
Electromagnetic fields generated by appliances, power lines and other sources can also potentially entrain the brain. It's one of the reasons why some sources will advise against sleeping with an alarm clock too close to your head. (The EM field of an alarm clock is much higher than the delta and theta ranges associated with sleep - it's thought for that reason that the alarm clock can interfere with sleep.)
There are also 'geomagnetic' fields created naturally which can entrain the brain just as an artificial EM field can.
IV Felt Entrainment
I was debating whether to include this category, but I think it's worth mentioning (since really bridges the gap to audio below). Any felt stimuli can potentially have brainwave entrainment effects. Think a device that generates vibrations, or somebody doling out a massage. Also, a recurring beat/rhythm from subwoofers - instances where it's more 'felt' than heard.
V Audio Entrainment
For me, this is the main category that I devote most of my time to playing with (although I do like to do visual entrainment also with strobe lights.)
Any repeating\recurring\periodic sound-based stimuli can potentially entrain the brain. This can be done by changing up any number of qualities about the sound :
* Volume - the sound fades in and out X times a second. (This is the classic 'gapper' effect sometimes heard in electronic music, and you may here it referred to as 'isochronic tones'.)
* Pitch - the pitch of the tone goes up and down X times a second.
* Panning - Using headphones, the tone cycles between the left and right ear X times a second.
This is just scratching the surface - literally any characteristic of the sound, if changed up X times a second, can potentially entrain the brain. Other characteristics that can be modulated -- the EQ, the tone color (timbre), the waveform (sinus, sawtooth, triangle, etc), and the phase between the left and right channels.
(Side Note : Cool Edit's 'Brainwave Synchronizer' feature made use of phase modulation. Cool Edit was ultimately acquired by Adobe, and became Adobe Audition -- the Brainwave Synchronizer effect was named the 'Binaural Auto-Panner'. I believe it still makes use of phase modulation.)
---
One other method of audio entrainment involves binaural beats and monaural beats.
Before we go any further, I want to make sure to distinguish between binaural beats and binaural recording, which are two different animals.
Binaural recording is a method of recording sound intended to create a realistic 3D environment. This is often with a microphone shaped like a human head, so it captures sound exactly as a human head would.
Now, with that out of the way, let's get into binaural and monaural beats :
* Binaural beats : This is a method of brainwave entrainment listened to through headphones. To generate an entrainment frequency, two audible tones are used, one in each ear. The difference between the two tones should subtract out to the intended entrainment frequency.
For example, if you want to entrain to 5 HZ (which would be used to promote sleep), you could do this by putting a 200 HZ tone in the left ear, and a 205 HZ tone in the right ear. The brain is going to try and reconcile the subtle difference between the two tones in each ear -- it will end up hearing a single tone, but it will also hear a series of beats - five beats a second. These 'beats' can entrain the brain.
One thing to note - if you play the audio through speakers instead of headphones, you'll end up getting monaural beats instead of binaural beats (see below). [There is an exception to this, but I don't want to over-complicate things - yet.]
* Monaural beats : Monaural are very similar to binaural beats, except instead of having the two tones separated between the left and right ears, you just overlap the two tones period. So, using the example above, you would layer a 200 HZ tone over 205 HZ tone. The end result can be played through standard speakers - headphones are not necessary. Where as binaural beats are formed by the brain trying to reconcile the difference in tones between the left and right ears, monaural beats are the result of the tones mixing in open air after coming out of the speakers.
I welcome any feedback you may want to offer - I don't know everything, so if you think I am botching up some detail below, feel free to call me on it in the comments section.
Additionally, if you think there are better ways for me to present this information, let me know.
I Visual Entrainment :
Lights flickering X times per second can be used to entrain in the brain into various mental states. Point in case - a strobe light flashing 20 times a second can be used to energize a crowd of people.
A variation on this theme - if one watches something moving/oscillating X times a second, this can also potentially be used to entrain the brain. (Example : A hypnotist swinging a timepiece or some other object on a chain to put somebody into a trance.)
II Motion Entrainment :
Any periodic motion a person experiences can also have brainwave entrainment effects.
Examples : A rocking chair, swinging on a swing, a mother gentling rocking a child in her hands, etc.
III Electromagnetic Entrainment
Electromagnetic fields generated by appliances, power lines and other sources can also potentially entrain the brain. It's one of the reasons why some sources will advise against sleeping with an alarm clock too close to your head. (The EM field of an alarm clock is much higher than the delta and theta ranges associated with sleep - it's thought for that reason that the alarm clock can interfere with sleep.)
There are also 'geomagnetic' fields created naturally which can entrain the brain just as an artificial EM field can.
IV Felt Entrainment
I was debating whether to include this category, but I think it's worth mentioning (since really bridges the gap to audio below). Any felt stimuli can potentially have brainwave entrainment effects. Think a device that generates vibrations, or somebody doling out a massage. Also, a recurring beat/rhythm from subwoofers - instances where it's more 'felt' than heard.
V Audio Entrainment
For me, this is the main category that I devote most of my time to playing with (although I do like to do visual entrainment also with strobe lights.)
Any repeating\recurring\periodic sound-based stimuli can potentially entrain the brain. This can be done by changing up any number of qualities about the sound :
* Volume - the sound fades in and out X times a second. (This is the classic 'gapper' effect sometimes heard in electronic music, and you may here it referred to as 'isochronic tones'.)
* Pitch - the pitch of the tone goes up and down X times a second.
* Panning - Using headphones, the tone cycles between the left and right ear X times a second.
This is just scratching the surface - literally any characteristic of the sound, if changed up X times a second, can potentially entrain the brain. Other characteristics that can be modulated -- the EQ, the tone color (timbre), the waveform (sinus, sawtooth, triangle, etc), and the phase between the left and right channels.
(Side Note : Cool Edit's 'Brainwave Synchronizer' feature made use of phase modulation. Cool Edit was ultimately acquired by Adobe, and became Adobe Audition -- the Brainwave Synchronizer effect was named the 'Binaural Auto-Panner'. I believe it still makes use of phase modulation.)
---
One other method of audio entrainment involves binaural beats and monaural beats.
Before we go any further, I want to make sure to distinguish between binaural beats and binaural recording, which are two different animals.
Binaural recording is a method of recording sound intended to create a realistic 3D environment. This is often with a microphone shaped like a human head, so it captures sound exactly as a human head would.
Now, with that out of the way, let's get into binaural and monaural beats :
* Binaural beats : This is a method of brainwave entrainment listened to through headphones. To generate an entrainment frequency, two audible tones are used, one in each ear. The difference between the two tones should subtract out to the intended entrainment frequency.
For example, if you want to entrain to 5 HZ (which would be used to promote sleep), you could do this by putting a 200 HZ tone in the left ear, and a 205 HZ tone in the right ear. The brain is going to try and reconcile the subtle difference between the two tones in each ear -- it will end up hearing a single tone, but it will also hear a series of beats - five beats a second. These 'beats' can entrain the brain.
One thing to note - if you play the audio through speakers instead of headphones, you'll end up getting monaural beats instead of binaural beats (see below). [There is an exception to this, but I don't want to over-complicate things - yet.]
* Monaural beats : Monaural are very similar to binaural beats, except instead of having the two tones separated between the left and right ears, you just overlap the two tones period. So, using the example above, you would layer a 200 HZ tone over 205 HZ tone. The end result can be played through standard speakers - headphones are not necessary. Where as binaural beats are formed by the brain trying to reconcile the difference in tones between the left and right ears, monaural beats are the result of the tones mixing in open air after coming out of the speakers.
Tuesday, August 11, 2015
Brainwave Frequency Ranges : The Big Five (Delta/Theta/Alpha/Beta/Gamma)
When it comes to Brainwave Entrainment, I guess the best place to start is at the beginning.
I had mentioned in a previous post that there are different 'ranges' of brainwaves generated by the brain, corresponding with different mental states.
These are the most common brainwave frequency ranges you'll encounter :
Delta Range (under 4 HZ) : Associated with deep sleep.
Theta Range (4 HZ to 8 HZ) : Associated with dreaming sleep.
Alpha Range (8 HZ to 13 HZ) : Associated with awake but relaxed states.
Beta Range (14 HZ to 35 HZ) : Associated with wide awake states. (Things head into the land of hyper vigilance as you reach the higher end of this range.)
Gamma Range (35 HZ to 45 HZ) : The borders of this range are kind of ill-defined. The center is generally thought to be around 40 HZ. This frequency range is associated with consciousness. When somebody is put under general anesthesia, brainwaves in the gamma range typically disappear.
---
While I could oversimplify and say that your brain is 'tuned' to a certain brainwave frequency at any point in time, that's not entirely accurate. There are brainwaves in all the different ranges simultaneously happening - the ratio of these brainwaves is what changes over time. (For instance, when you're in deep sleep, the most dominant brainwave frequencies are in the delta range.)
Another thing to point out is that there's a lot of variation as to where different sources say the various brainwave frequency ranges begin and end. It seems like there is more agreement for the Delta and Theta ranges, but once you start to get to the upper limit of the Alpha range, that's where there's more disagreement.
You may also see some other brainwave frequency ranges get thrown into the mix (Epsilon/Lambda), but I'm leaving them out of the equation for now. (They're not as commonly used.)
I had mentioned in a previous post that there are different 'ranges' of brainwaves generated by the brain, corresponding with different mental states.
These are the most common brainwave frequency ranges you'll encounter :
Delta Range (under 4 HZ) : Associated with deep sleep.
Theta Range (4 HZ to 8 HZ) : Associated with dreaming sleep.
Alpha Range (8 HZ to 13 HZ) : Associated with awake but relaxed states.
Beta Range (14 HZ to 35 HZ) : Associated with wide awake states. (Things head into the land of hyper vigilance as you reach the higher end of this range.)
Gamma Range (35 HZ to 45 HZ) : The borders of this range are kind of ill-defined. The center is generally thought to be around 40 HZ. This frequency range is associated with consciousness. When somebody is put under general anesthesia, brainwaves in the gamma range typically disappear.
---
While I could oversimplify and say that your brain is 'tuned' to a certain brainwave frequency at any point in time, that's not entirely accurate. There are brainwaves in all the different ranges simultaneously happening - the ratio of these brainwaves is what changes over time. (For instance, when you're in deep sleep, the most dominant brainwave frequencies are in the delta range.)
Another thing to point out is that there's a lot of variation as to where different sources say the various brainwave frequency ranges begin and end. It seems like there is more agreement for the Delta and Theta ranges, but once you start to get to the upper limit of the Alpha range, that's where there's more disagreement.
You may also see some other brainwave frequency ranges get thrown into the mix (Epsilon/Lambda), but I'm leaving them out of the equation for now. (They're not as commonly used.)
Saturday, August 8, 2015
Resurrecting The Acoustic Phoenix
This is going to be an attempt to bring back the old Sonic Alchemy Logbook that I used to produce on the Papercut Suicide website about 15 years ago :
http://lunarsight.com
A little about the website :
That website evolved out of a Geocities site I created in 1996, and it certainly looks its age. I think any modern web developer would probably have an aneurysm reading the HTML code that went into that page. It's equal parts Netscape Navigator and Microsoft FrontPage, and it's a testament to the backwards compatibility of the internet that the page still works at all. (Not only does it still work, but it shockingly looks pretty good from mobile devices -- I'm not sure how the heck that happened.)
Now that I've given the back history of the main website, I'll go on the record and indicate probably nobody cares about most of the website. Like many websites from the early internet, it was primarily a place to post poetry, art, animated gifs, and random links to random things.
However, it seems that one subset of pages did and still do get a lot of attention. That being the Brainwave/Cymatic Frequency List :
http://lunarsight.com/freq.htm
Brainwave Entrainment :
In the late 90s / early 00's, I was heavily interested in computer-generated music and sounds. Early on, I used a sound editor called CoolEdit for much of my early experimentation. One feature of CoolEdit was a way to create sounds that entrained the brain to certain mental states.
I'll get more into this later, but to quickly summarize brainwave entrainment now, it's a method of using sound, light (and other stimuli) to coax the brain into various mental states (wide awake, asleep, etc).
Let me provide a simple visual example - A strobe light.
If a strobe light is flickering 15 times a second, the brain is going to try and replicate this rate with its own brainwaves. (The brain plays monkey-see/monkey do with the stimuli.)
Now, different brainwave rates are associated with different mental states.
Basically, slower brainwaves (under 7 HZ) are associated with sleep. Higher brainwaves (8 HZ and above) are associated with being awake. Generally, the higher up you go, the more wide awake you are. So, 10 HZ would be awake but fairly relaxed. Whereas at 20 HZ and higher, you're playing some intense fighting video game, and are putting every ounce of concentration into not getting your butt kicked by the other guy. [Read : You're as wide awake as wide awake can possibly be.]
Back To The Frequency List :
As I got deeper into experimenting with sound, I began to play with other sound-based applications. I was big on fractal music generators for a while, and when I was doing more monotonous data entry work, I often would have the fractal music playing indefinitely, to keep my brain occupied.
I also began to use an application called Brainwave Generator, which like Cool Edit, had a method of creating sounds to entrain the brain. (I'll come back to all the brainwave entrainment methods in a later post. There are all manner of different ways to do it, and the individual methods don't exist in a vacuum either. You can mix and match them together.)
Anyway -- I began to find all manner of different websites online indicating different frequencies associated with different things. The nature of the frequencies weren't just limited to brainwave entrainment. They covered ground associated with other 'sound healing' methods [chakras, for instance]. Also, some of the frequencies weren't associated with sound at all. [Rife Frequencies were presumably used for healing, but the healing was doled out via machines that produced 'energy'.]
I began to compile a list of all the frequencies I came across.
The list was originally intended for my own personal experimentation. I was heavily dabbling in electronic music at the time, and the frequency list served as a 'sound dictionary' for me. For instance, if I wanted to represent the planet Mars in a track, what better way to do it than use a sound frequency that was calculated right from the revolution/rotation of the planet? (That really appealed to my inner geek.)
I ultimately decided to post the frequency list online, figuring there may be some other people out there who would find some use in it (or at least get a laugh out of it).
Again, this was when the internet was still young, and people were more interested in just sharing information rather than making a profit off everything.
The Sonic Alchemy Logbook
For a while, I was posting my sonic experimentation to a separate page on Papercut Suicide. It can be found here :
http://lunarsight.com/son-alc.htm
I also included samples of the sonic experimentation for other people to download. Brainwave Generator presets were my preferred method of posting the samples, since the preset files were usually pretty small. I sometimes would also post WAV files for limited periods of time (although file size was often a problem - there was limited storage back then).
Ultimately, I stopped updating the logbook, since I was going into the HTML each time I wanted to add an entry, and it was a pain in the neck.
Blog-GING? Can I HAS Blog-GING?
I had been considering bringing back the Sonic Alchemy Logbook for years.
I kept on hearing about this 'blog' thing, which supposedly made it super easy to post information without even having to code anything in HTML. (What manner of sorcery is this??)
I began searching for a blogging site to use, only to find out I already had one. (Apparently the multi-headed Hydra that is Google had Blogger as part of its lists of services.)
So, here I am -- hopefully I can maintain this blog over time (provided there are no lapses in my attention span, which is typically pretty good as long as I steer clear of butterflies and other small distracting mammals -- like squirrels, who I think were put on this earth simply to distract humans with their silly antics.)
Mike / Papercut Suicide
http://lunarsight.com
A little about the website :
That website evolved out of a Geocities site I created in 1996, and it certainly looks its age. I think any modern web developer would probably have an aneurysm reading the HTML code that went into that page. It's equal parts Netscape Navigator and Microsoft FrontPage, and it's a testament to the backwards compatibility of the internet that the page still works at all. (Not only does it still work, but it shockingly looks pretty good from mobile devices -- I'm not sure how the heck that happened.)
Now that I've given the back history of the main website, I'll go on the record and indicate probably nobody cares about most of the website. Like many websites from the early internet, it was primarily a place to post poetry, art, animated gifs, and random links to random things.
However, it seems that one subset of pages did and still do get a lot of attention. That being the Brainwave/Cymatic Frequency List :
http://lunarsight.com/freq.htm
Brainwave Entrainment :
In the late 90s / early 00's, I was heavily interested in computer-generated music and sounds. Early on, I used a sound editor called CoolEdit for much of my early experimentation. One feature of CoolEdit was a way to create sounds that entrained the brain to certain mental states.
I'll get more into this later, but to quickly summarize brainwave entrainment now, it's a method of using sound, light (and other stimuli) to coax the brain into various mental states (wide awake, asleep, etc).
Let me provide a simple visual example - A strobe light.
If a strobe light is flickering 15 times a second, the brain is going to try and replicate this rate with its own brainwaves. (The brain plays monkey-see/monkey do with the stimuli.)
Now, different brainwave rates are associated with different mental states.
Basically, slower brainwaves (under 7 HZ) are associated with sleep. Higher brainwaves (8 HZ and above) are associated with being awake. Generally, the higher up you go, the more wide awake you are. So, 10 HZ would be awake but fairly relaxed. Whereas at 20 HZ and higher, you're playing some intense fighting video game, and are putting every ounce of concentration into not getting your butt kicked by the other guy. [Read : You're as wide awake as wide awake can possibly be.]
Back To The Frequency List :
As I got deeper into experimenting with sound, I began to play with other sound-based applications. I was big on fractal music generators for a while, and when I was doing more monotonous data entry work, I often would have the fractal music playing indefinitely, to keep my brain occupied.
I also began to use an application called Brainwave Generator, which like Cool Edit, had a method of creating sounds to entrain the brain. (I'll come back to all the brainwave entrainment methods in a later post. There are all manner of different ways to do it, and the individual methods don't exist in a vacuum either. You can mix and match them together.)
Anyway -- I began to find all manner of different websites online indicating different frequencies associated with different things. The nature of the frequencies weren't just limited to brainwave entrainment. They covered ground associated with other 'sound healing' methods [chakras, for instance]. Also, some of the frequencies weren't associated with sound at all. [Rife Frequencies were presumably used for healing, but the healing was doled out via machines that produced 'energy'.]
I began to compile a list of all the frequencies I came across.
The list was originally intended for my own personal experimentation. I was heavily dabbling in electronic music at the time, and the frequency list served as a 'sound dictionary' for me. For instance, if I wanted to represent the planet Mars in a track, what better way to do it than use a sound frequency that was calculated right from the revolution/rotation of the planet? (That really appealed to my inner geek.)
I ultimately decided to post the frequency list online, figuring there may be some other people out there who would find some use in it (or at least get a laugh out of it).
Again, this was when the internet was still young, and people were more interested in just sharing information rather than making a profit off everything.
The Sonic Alchemy Logbook
For a while, I was posting my sonic experimentation to a separate page on Papercut Suicide. It can be found here :
http://lunarsight.com/son-alc.htm
I also included samples of the sonic experimentation for other people to download. Brainwave Generator presets were my preferred method of posting the samples, since the preset files were usually pretty small. I sometimes would also post WAV files for limited periods of time (although file size was often a problem - there was limited storage back then).
Ultimately, I stopped updating the logbook, since I was going into the HTML each time I wanted to add an entry, and it was a pain in the neck.
Blog-GING? Can I HAS Blog-GING?
I had been considering bringing back the Sonic Alchemy Logbook for years.
I kept on hearing about this 'blog' thing, which supposedly made it super easy to post information without even having to code anything in HTML. (What manner of sorcery is this??)
I began searching for a blogging site to use, only to find out I already had one. (Apparently the multi-headed Hydra that is Google had Blogger as part of its lists of services.)
So, here I am -- hopefully I can maintain this blog over time (provided there are no lapses in my attention span, which is typically pretty good as long as I steer clear of butterflies and other small distracting mammals -- like squirrels, who I think were put on this earth simply to distract humans with their silly antics.)
Mike / Papercut Suicide
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