With almost 100 years of research validating the effectiveness of brainwave entrainment, it’s no wonder why it’s used by thousands of people all over the world. What does the future entail in this exciting field? With the adoption of smartphones, virtual and augmented reality, and advancements in technology reducing the cost of EEG and other forms of biofeedback devices, the entrainment possibilities are endless.

Since most of us spend our days in the beta state, EquiSync excludes the beta brainwave frequencies, and entrains only those responsible for the most beneficial brainwave states: alpha, theta, and delta waves. The two charts on this page illustrate the basic benefits of each brainwave state as well as the basic targeting of the EquiSync programs 1, 2, & 3.
The Transparent Corp forum – This forum is an invaluable resource for any brainwave entrainment user or enthusiast.  Most of the feedback is obviously focused on the Transparent Corp software, but with over 20,000+ posts now you can find answers to the whole array of brainwave entrainment questions on there.  (UPDATE: Sadly, the Transparent Corp forum has now been taken offline)
Besides scientific literature, some authors have written of the promising research on meditation in books targeted for general audiences. One such book, Buddha’s Brain by Rick Hanson, PhD shares the current scientific research and investigations into meditation.[19] Hanson, a neuroscientist and researcher, explains to readers the scientific studies in plain language and discuss the impact of the results. Hanson’s main argument is that positive emotions, like love can be strengthened through meditation in a neuroplastic manner, citing dozens of scientific studies to support this claim.[19] Hanson’s viewpoint is representative of a larger popular movement to study and embrace Eastern phenomena including meditation in the Western world.

Beta brainwaves are next highest in frequency after alpha waves, occurring at 13 to 30 hertz. Beta brainwaves are what we experience every day as we are awake and using our analytic mind. Beta brainwaves are needed for concentrating on mental tasks, and when they are present for too long of a time, they lead to stress, anxiety, and even paranoia. Most people do not have trouble achieving beta brainwaves and in fact suffer from spending too much time in beta brainwave patterns. However, those with attention deficit disorder (ADD) who have problems focusing their attention can benefit from learning how to achieve and remain in beta brainwave states for longer amounts of time.

“In order to get into a flow state, you have to calm a part of the brain, the posterior cingulate cortex, which is the source of what brain scientists call the default state, which is the non-focused state,” says Harris. “At any rate, it turns out that Holosync [binaural beats], when you listen to it, [calms that part of the brain] and so does traditional meditation. It’s just Holosync does it faster and more easily and more effortlessly. It turns down the posterior cingulate cortex and it enhances the other part of the brain that, when it’s enhanced, you can easily go into a flow state.”
Gamma brainwaves occur during creative thinking and processing of memory and language and in many learning activities. These brainwaves are not present at all when a person is under anesthesia, but return as soon as the person becomes conscious again. Multiple scientific studies have shown gamma brainwave entrainment to be helpful for reducing distractibility, improving short-term memory, improving motor coordination, and relieving migraine headaches.
You may recognize the "binaural recording" from ASMR, where the technique is often used. This explains why, if you search for "binaural" on YouTube, you get a mixture of two entirely different kinds of results: binaural beats and binaural ASMR recordings. It gets especially confusing in that there's some questionable and/or unexplored science surrounding each one.
Results of this research proved that, indeed, the brain would entrain itself to the frequency equal to the difference between the two frequencies played. So if a subject listened to a 210 hertz tone in one ear and a 214 hertz tone in the other, the 4 hertz difference is the perceived “beat” that the brain, after listening for a while, will match itself to.
Also, don’t you think that the inherent hemispheric synchronization using binaural beats might be a positive benefit within itself? While it’s true that the huge majority of us use both sides of our brains most of the time, it’s also true that many of us are a bit polarized to one side or the other in general, or when doing a particular kind of activity or focus. I’ve found stimulating a more equally and consistently whole brain activity has it’s own benefits other than the entrainment aspect.
As a relatively new technology, fMRI has only recently been used to assess brain state changes during meditation. Recent studies have shown heightened activity in the anterior cingulate cortex, frontal cortex, and prefrontal cortex, specifically in the dorsal medial prefrontal area during Vipassana meditation.[7] Similarly, the cingulate cortex and frontal cortex areas were shown to have increased activity during Zen meditation.[8] Both studies comment on the possibility that these findings could indicate some state of heightened voluntary control over attention during mindfulness meditation. Review works by Cahn and Chiesa state that these results indicate consistency in meditation’s effect on these regions of the brain, citing a multitude of other studies spanning other meditative disciplines, but mention the need for further investigation with better controls.[4][6]
a concise P.S. I was in a horrible car accident when I was 18 and had to learn to read and write and walk and talk all over again. It was long ago and I’m pretty well over it, but such an injury has lifetime repercussions. The neurological damage sustained causes my left arm to shake uncontrollably anytime I use it in a situation requiring precise coordination. From simply listening to the demo, the shake [though not disappearing completely in the last 2 months] has lessened dramatically. I had been wondering for years what kind of neurological exercises I could undergo to help it…
There is a solution, which, although you may not have heard about it, has been around (and scientifically tested!) for decades now. By using binaural beats, you can ease your brain from its active state into a more restful state simply by listening to a different frequency wavelengths of sound in each ear. Because two different wavelengths are entering through two different entrances (your ears), that difference is perceived as a “beat” (though it may sound like a warble to some) that resonates at the frequency equal to the difference. The brain will entrain (match) itself to the beat produced by the difference in wavelengths. If the difference between the two wavelengths is less than seven hertz, your brain will fall into a state of deep relaxation, also known at the theta range.
Binaural beats change the frequency of your brainwaves, giving you control over which category you experience at any given moment. And because you’re in the driver’s seat — and producing specific frequencies to induce a specific state of mind — you can use binaural beats to boost performance, increase focus, get better sleep… the possibilities are endless. “There’s an infinite number of variations on how you could use this kind of technology,” says Bill Harris, Director of Centerpointe Research Institute and creator of auditory brainwave training program Holosync.
I first became aware of brainwave meditation programs  and brain waves when researching alternative methods for treating the bipolar disorder I had been unsuccessfully living with my entire adult life. I eventually learned a method of releasing difficult emotions on the spot, which I then practiced extensively, and consequently found it easier and even desirable to meditate for fairly lengthy periods of time. Though I took up meditation as a serious daily practice and experienced many undeniable benefits, I nonetheless intermittently experienced life-debilitating bouts of mania and severe depression, often resulting in chaotic mixed states and an inability to maintain daily social functions. During these times, it became nearly impossible to sit in meditation.

Generally speaking, the brain will usually entrain to the strongest stimulus which would be isochronic tones over binaural beats. So when you see people add binaural beats at a different frequency to the isochronic tones, that would not produce additional brainwave entrainment at another frequency. If they are both at the same frequency I haven’t seen any research to indicate whether that would be beneficial or not, but my belief is that it would weaken the potential for entrainment. When you look at the waveform of an isochronic tone there is a distinct empty space between each beat, making it very pronounced and effective. When you add binaural beats at the same frequency it looks like this: http://www.mindamend.com/wp-content/uploads/2017/11/isochronic-tones-binaural-beats-combined-waveform.jpg. The depth of the waveform is now half as deep and less effective. This is before the binaural beats are formed inside your head, where the waveform is hard to determine and measure. From listening to that type of combination the beats sound much less pronounced, which has to make them much less effective in terms of a brainwave entrainment stimulus, compared to isochronic tones on their own.
A study published in Electroencephalography and Clinical Neurophysiology by Paul Williams and Michael West in 1975 examined the brainwave states of people experienced in meditation while using photic stimulation, and another study by Leonard, Telch, and Harrington in 1999 examined the successful use of brainwave entrainment techniques for attaining meditative states in subjects.
"Wow! I have been doing this Awakening Kundalini guided meditation every morning for about two weeks now. I am a yoga teacher and I have never experienced energy like this before! Every morning, I feel a surge and abundance of endless vital energy nourish my mind, body, and soul. The sounds, theta waves and guidance are perfectly combined to gently awaken the sleeping serpent confirmed by the exquisite sensations experienced. "  --Katarine
The effects are strongest while you are listening to the tones because your brainwaves are synchronized and tuned into the frequency range you desire at that time.  After you've stopped listening the effects can still linger for a while afterwards.  The timescale will vary from person to person and be affected by what you do after you've stopped listening.
In order to take full advantage of binaural beats to tackle insomnia, you should first buy a high-quality recording. Although it’s true that any two tones that have wavelengths that are seven hertz or less fewer apart will create a binaural beat, there are other factors to take into consideration. Many people find the tones that create binaural beats unpleasant, so a good recording will also have a “pink noise” to help mask the sound (falling rain is one popular such noise).; this noise will also help you focus on the binaural beat instead of letting your mind wander.
Over the centuries people have discovered that repetitious rhythms such as the beating of a drum at a single tone, or chanting, or other methods for producing a single, repetitious rhythm, have been known to produce certain states of consciousness whether deep relaxation, trance, a state of meditation and so on. The rhythms used basically changed the brainwave state of the person listening as long as that person remains open and receptive to the rhythms.

I was recently asked a question by my nephew, regarding binaural beats. Because of my involvement with meditation and relaxation techniques, he felt comfortable asking about the safety of it and what it was, exactly. I provided him with some information that I felt would assist him in his choice, as to whether or not to listen, and I decided to do a little more research on the subject, in order to better educate myself. I know a little about the topic, but I wanted to know more about it.

The gentle pulsating rhythms of Brain Sync audio programs act in a similar fashion, yet because the frequencies are precise and consistent they can be targeted to induce highly specific and desired brain states. Just as you can tune a radio to get a particular station, with Brain Sync technology you can re-tune your consciousness – effectively dialing your mind into a wide variety of brain states.
Pure tones played together interfere with each other when they are close in pitch but not identical. When each tone is sent to a different ear, there will not be any physical interaction between the waves, yet your brain still creates an interference inside your head: the so-called binaural beat. In order to create a binaural beat, each ear must receive its dedicated signal. Therefore, binaural beats only work through headphones.