So using the example track above, the right ear is sent a 20Hz beat, compared to a 10Hz beat in the left ear.  As the right ear receives the higher frequency of beat, this works to increase the speed of the ‘left' brain hemisphere, which can be helpful for people with conditions like ADD, who are often found to have an abundance of slow wave activity in the left brain.
For example if you play a tone of 200hz in the left ear, and a tone of 190hz in the right ear (with the difference being 10hz) a beating tone will be perceived at 10 hz which is the binaural beat. What ever the difference is between the tones coming into the ears (in this example the difference is 200hz-190hz=10hz) the binaural beat will be that difference.
The review by Cahn also notes findings describing a heightened emotional state of meditators. A more complex study, conducted in 2008 by Lutz et al., focused on emotional response during meditation.[9] This investigation involved the creation of a “compassion meditation” state by novice and experienced meditators and testing the meditators response to emotionally charged sounds. fMRI results indicated heightened activity in the cingulate cortex but also in the amygdala, temporo-parietal junction, and right posterior superior temporal sulcus in response to the emotional sounds. The authors of this study believe this indicates greater sensitivity to emotional expression and positive emotion due to the neural circuitry activated.[9]

Beta: These brainwaves are associated with high levels of alertness and arousal. When beta brainwave patterns dominate, we’re primed to focus and concentrate, to make decisions and think analytically. When you’re analyzing an issue at work, you’re probably in a beta-dominant state. Beta waves are fast, with a higher frequency (between 15-40 hertz). At the higher levels of this range, beta waves are associated with anxiety.
Over the long term, traditional eastern methods (such as meditation and yoga) train your brainwaves into balance. Of the newer methods, brainwave entrainment is an easy, low-cost method to temporarily alter your brainwave state. If you are trying to solve a particular difficulty or fine-tune your brainwave function, state-of-the-art brain training methods like neurofeedback and pEMF deliver targeted, quick, and lasting results.  
All brainwave frequencies are useful and beneficial at certain times – there is no brainwave that is intrinsically better than another. However, by deliberately choosing to attain a particular brainwave state, a corresponding mental state can be brought about at the same time. For example, a working person who has been in an overly alert beta brainwave pattern for many hours can quickly shift their mind and body into a relaxed state by listening to a few minutes of brainwave entrainment music for inducing alpha or theta brainwaves.
A therapy that slows brainwave activity, helping to produce low frequency waves, is likely to aid relaxation and sleep. But it’s not only lowering brainwave frequency that binaural beats may offer to sleep and relaxation. A small study (19 people) has found that exposure to binaural beats is associated with changes to three hormones important to sleep and well being:
While visual entrainment is more powerful than audio alone for inducing desired brainwave states, more caution is needed when using visual methods. Between 0.3 and 3 percent of the population is susceptible to having seizures from flickering light stimulation, and for other people, flickering visual stimuli simply makes them uncomfortable. People with epilepsy have a greater chance of having a seizure from exposure to flickering light stimulation.

Hi Ulka, thanks for your compliment on my article. Unfortunately, I haven’t come across any studies or much discussion about the problem with habituation and isochronic tones and how to overcome it. The consensus among experienced users is to regularly change the frequencies and music soundtracks you listen to. Adding music to the tones does change the waveform you are stimulated with, so that’s one of the main reasons why I provide different soundtracks for my isochronic tones sessions. I have released some tracks which use amplitude modulations in the music, instead of isochronic tones. It might be worth giving them a try if you haven’t already. I have them in a playlist on YouTube

Slow Wave Sleep or SWS, is the deepest of sleep states and it plays a vital role in health and well being. During this phase of the sleep cycle, the brain begins producing very slow, large Delta waves. Even if your lifestyle doesn’t allow for the luxury of a full eight hours of sleep, a few hours of Slow Wave Sleep will trick your brain into thinking it’s had all the restorative sleep it needs.

Some studies have found that binaural beats can affect cognitive function positively or negatively, depending on the specific frequency that’s generated. For example, a study of long-term memory found that beta-frequency binaural beats improved memory, while theta-frequency binaural beats interfered with memory. This is something for scientists to continue to examine closely. For people who use binaural beats, it’s important to understand that different frequencies will produce different effects.
Slightly higher-frequency entrainment can lead to hyper suggestive states of consciousness. Still higher-frequency EEG states are associated with alert and focused mental activity needed for the optimal performance of many tasks. Perceived reality changes depending on the state of consciousness of the perceiver (Tart, 1975). Some states of consciousness provide limited views of reality, while others provide an expanded awareness of reality. For the most part, states of consciousness change in response to the ever-changing internal environment and surrounding stimulation. For example, states of consciousness are subject to influences like drugs and circadian and ultradian rhythms (Rossi, 1986; Shannahoff-Khalsa, 1991; Webb & Dube, 1981). Specific states of consciousness can also be learned as adaptive behaviors to demanding circumstances (Green and Green, 1986).  

The pitch frequency measures and describes what a beat sounds like, i.e. does the isochronic beat have a deeper bass sound, or is it high pitched and sharper sounding? The beat waveform frequency describes how many times the beat is repeating per second, i.e. how fast it is beating. You don’t really need to concern yourself about the pitch frequency, as that doesn’t have a direct influence on brainwave entrainment and doesn’t play a part on the measurement on an EEG. I only mentioned it because you were referring to humans not being able to hear below 20Hz. I change the pitch frequency just to suit the mood of the track. For tracks that are to be relaxing, for meditation or sleep, I tend to use a lower pitch frequency so it sounds deeper and more relaxing and I never have that lower than 100Hz. For an energizing, high focus track I might use a more higher pitched 200Hz isochronic tone, because that is sharper sounding and less likely to make you feel sleepy. That’s all you really need to know about the pitch frequency.
By the end of just a few short days (3 or 4 of use), my constant “on edge” feeling completely dissipated. I had changed my lifestyle drastically to a very low-stress environment. All feelings of anxiety disappeared rapidly, but I was still experiencing something “physical.” I had trouble explaining it to anyone. I lashed out immediately at the slightest frustration. I tried to explain to those around me that it was something physically happening in my brain, but they were skeptical. Within less than a week of using the EOC cd’s, I noticed my tolerance level for dealing with people and situations had increased tremendously.
Some studies have found that binaural beats can affect cognitive function positively or negatively, depending on the specific frequency that’s generated. For example, a study of long-term memory found that beta-frequency binaural beats improved memory, while theta-frequency binaural beats interfered with memory. This is something for scientists to continue to examine closely. For people who use binaural beats, it’s important to understand that different frequencies will produce different effects.

Joseph Kao, creator of Profound Releasing, Profound Renewal, and Sound Asleep, is a hypnotherapist and a solution-focused therapist with a private practice in Cambridge, UK. Joe was the co-developer of an acclaimed course on conversational hypnosis, and he regularly teaches hypnotherapy and psychotherapy to other therapists. He has also been the head scriptwriter for over 800 professional hypnotherapy recordings. Joe was drawn to the world of philosophy, meditation, and brainwave entrainment technology from an early age, and he’s had a daily meditation practice since 1998.

In 1984 medical researcher Dr. Gene W. Brockopp published a paper making several conclusions of audio and visual entrainment (AVE). Such conclusions were that hemispheric synchronization caused by AVE is related to increased intellectual functioning, practiced use of AVE overtime leads to a cumulative effect, and AVE may result in the recovery of early childhood experiences.

Our relaxing music is perfect for Deepak Chopra Meditations, Buddhist meditation, Zen meditation, Mindfulness meditation, Kundalini meditation, Qi Gong Meditation, Zazen Meditation and more. Our music is influenced by Japanese meditation music, Indian meditation music, Tibetan music and Shamanic music. Our instrumental music has been designed to encourage and enhance relaxation, meditation, brain function and concentration, spa and massage therapy, and healing music therapy. In addition, we use binaural beats (Delta, Alpha and Theta Waves) to naturally reach a state of relaxation perfect for concentration, meditation or deep sleep. Our music playlists are perfect for your daily meditation and relaxation. Our music videos use soundscapes such as nature sounds, animals, oceans, rain sounds, thunder sounds and many more).
Gamma was dismissed as 'spare brain noise' until researchers discovered it was highly active when in states of universal love, altruism, and the ‘higher virtues’. Gamma is also above the frequency of neuronal firing, so how it is generated remains a mystery. It is speculated that gamma rhythms modulate perception and consciousness, and that a greater presence of gamma relates to expanded consciousness and spiritual emergence.
Further experimentation showed that the difference between the two frequencies must be relatively small – under 30 hertz – for it to be perceived as a “beat”; frequencies with greater difference are perceived separately. Using binaural beats in various mental states while being recorded by an EEG (encepl…blahFIX) allowed researchers to further delineate the different wavelengths the human mind generates for different states of being. The categories are generally agreed upon as (from most to least “active” states): Gamma (extreme emotions or intense concentration), Beta (active thinking, concentration, anxiety, arousal), Alpha (drowsy, falling-asleep feeling, sometimes also general relaxation), Theta (dreaming sleep or deep meditation), and Delta (deep, dreamless sleep), but the wavelengths at which each occurs are not set in stone, though they generally run as over 40 hertz for Gamma, 13 to 29 for Beta, 7 to 13 for Alpha, 4 to 7 for Theta, and under 4 hertz for Delta.
Because of the way they are created, there may be a positive benefit from listening to binaural beats without considering the brainwave entrainment aspect, but I haven’t seen any research on that. I first discovered brainwave entrainment through binaural beats about 10 years ago now, but they didn’t do anything for me. So I’ve never been a regular user of them. I believe isochronic tones are a more effective way to produce hemispheric synchronisation because they produce a much stronger response in the brain
The power and manifold benefits of meditation are well documented, its practice dating back to prehistory where it was used mainly for religious or spiritual purposes. With our growing knowledge and understanding of the functions of the brain it seems both logical and practical that we should develop ways of tapping into this power and using it to our advantage.
I forgot to tell you, after using your meditation for a few weeks, I woke up one morning with the most vivid recollection of having an out of body experience […shortened…] I am hoping to experience this again and control myself the next time. Thank you for enabling me to remember this extraordinary experience. I never believed they were real until I used your program.
There is also evidence to suggest meditation plays a protective role against the natural reduction in grey matter volume associated with aging. One study found evidence that Zen meditators experienced a slower age related decline rate for cerebral gray matter volume in the putamen which plays a role in learning, cognitive flexibility and attentional processing [14] This could suggest a better attentiveness in aging meditators versus non-meditators.
A person driving on a freeway, who discovers that they can't recall the last five miles, is often in a theta state - induced by the process of freeway driving. This can also occur in the shower or tub or even while shaving or brushing your hair. It is a state where tasks become so automatic that you can mentally disengage from them. The ideation that can take place during the theta state is often free flow and occurs without censorship or guilt. It is typically a very positive mental state.

Well, except for one reason: The power of suggestion. If I give you a music track and tell you that it will cure your headache, you're more likely to report that it cured your headache than you are to say "Well it didn't effect my headache, but it made my short-term memory better." An interesting experiment would be to buy a binaural track claimed to induce drunkenness, for example; play it for five friends without telling them the claim, and then ask how it made each of them feel. Give them multiple choices to select from. Chances are they're going to respond all over the map. If you have a friend who is a believer in binaural beats, I suggest going ahead and setting up this little test.