4. Be hesitant committing to any BWE system making wild claims. Profit fueled marketers with little to no experience in the BWE field have created a slew of low-quality entrainment systems on the market. These products typically make outrageous promises such as permanently enhancing the brain within minutes of use. Although BWE is a powerful method to improve the mind, it’s not a magic bullet.
"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

I am one of the fortunate ones who received a free demo of your product. I do believe your product corrected damage to my brain from a childhood concussion. Immediately upon use, I became aware of sounds, drainage and even discomfort behind my right eye and the lower right side of my skull. This continued for a week of using the product daily. I was about to give up using the product when all discomfort stopped, and has not returned. I do believe your product should be used for childhood head trauma. Even though the brain is only bruised, a life can be altered immensely. I love my Equisync II and will use it daily and with confidence.
If mind-consciousness is not the brain, why then does science relate states of consciousness and mental functioning to Brainwave frequencies? And how is it that audio with embedded binaural beats alters brain waves? The first question can be answered in terms of instrumentation. There is no objective way to measure mind or consciousness with an instrument. Mind-consciousness appears to be a field phenomenon which interfaces with the body and the neurological structures of the brain (Hunt, 1995). One cannot measure this field directly with current instrumentation. On the other hand, the electrical potentials of brain waves can be measured and easily quantified. Contemporary science likes things that can be measured and quantified. The problem here lies in oversimplification of the observations. EEG patterns measured on the cortex are the result of electro-neurological activity of the brain. But the brain's electro-neurological activity is not mind-consciousness. EEG measurements then are only an indirect means of assessing the mind-consciousness interface with the neurological structures of the brain. As crude as this may seem, the EEG has been a reliable way for researchers to estimate states of consciousness based on the relative proportions of EEG frequencies. Stated another way, certain EEG patterns have been historically associated with specific states of consciousness. It is reasonable to assume, given the current EEG literature, that if a specific EEG pattern emerges it is probably accompanied by a particular state of consciousness.  
A good recording will also not immediately start with tones that produce the theta range, but will begin higher up, in the beta range (which is associated with anxiety, but also active concentration and other waking states of being), and gradually move down, through the alpha range (which is the ideal meditative wavelength, but is also associated with falling asleep) before moving into the final, theta, range. If you get a binaural beat that goes directly into the theta range, you might find yourself distracted or unable to sync up as easily.
Cory Allen [b. 1982] is a composer and mastering engineer living in Austin, Texas. His work focuses on the cultivation of human perception with the intent of altering the listener's state of consciousness. Allen's music is deep, patient, meditative, highly-conceptual and often composed by implementing self-organizing structures, rule-based performances, set pitch classes and a wide variety of instruments.
Brainwave Entrainment has been used possibly as far back as 200AD, where Ptolemy of the Ancient Greeks noted the effect of flicking sunlight created by a spinning wheel. The first recorded clinical application was by a French psychologist, who again used a spinning wheel but this time illuminated with a lantern instead of the sun. He noted that his patients appeared calmer when they looked into the flickering light, so he used it as a relaxation technique whenever it was needed.
Theta brainwaves in the frequency range of 6 to 9 hertz are known as thalpha waves because of their proximity to alpha waves. They are seen during states of high suggestibility, during hypnosis, and during paranormal experience and are also connected to an increase in human growth hormone (HGH) levels and higher blood flow to the brain. Theta brainwaves sit between the realms of the subconscious and conscious mind, making them an especially useful brainwave state for developing creative thinking, working through emotional problems, and integrating subconscious and conscious experience. 

Meanwhile, the therapeutic benefits of listening to sound and music is a well-established principle upon which the practice of receptive music therapy is founded. The term 'receptive music therapy' denotes a process by which patients or participants listen to music with specific intent to therapeutically benefit; and is a term used by therapists to distinguish it from 'active music therapy' by which patients or participants engage in producing vocal or instrumental music.[37] Receptive music therapy is an effective adjunctive intervention suitable for treating a range of physical and mental conditions.[38]
^ Trost W. and Vuilleumier P., Rhythmic entrainment as a mechanism for emotion induction by music: a neurophysiological perspective. In The Emotional Power of Music: Multidisciplinary Perspectives on Musical Arousal, Expression, and Social Control, Cochrane T., Fantini B., and Scherer K. R., (Eds.), Oxford, UK: Oxford University Press; 2013, pp213–225.
I have read something different about theta waves and learning languages. A University of Washington study tested students resting brainwave activity before learning French. They found that students with a higher amount beta/gamma and a lower amount of delta/theta activity were better at acquiring a second language. When you are dominant in theta, that is the lowest and most deeply relaxed awakened state you can be in. I think it would be much harder to really concentrate, fully understand and learn new information while in a theta state, so I would personally consider using theta while studying.
Brainwave entrainment through the use of binaural beats is a scientific method that helps you go from alert to relaxed to asleep within minutes by using a process to alter your brainwaves. Sounds like something straight out of a science fiction novel, but brainwave entrainment is a very real and very effective way to help you sleep. Your alertness is linked to the dominant frequency of your brainwaves. So if you’re feeling alert and focused, your brainwaves are in the beta frequency but if you’re feeling relaxed, they’re likely to be in the alpha state. To sleep, your brainwave frequency needs drop to a slow delta. This can be hard, especially after a busy day. Your brain stays alert, preventing you from relaxing. By using Binaural Beats, you can quickly induce the frequencies associated with sleep in your brain within minutes.  Scientists discovered that the brain synchronises itself to a dominant frequency. So by inducing a new lower frequency with binaural beats, your brain begins to lower its own frequency to match this new frequency. It’s a powerful technology that I’ve been using myself for years with very good results.
This research investigates the brainwave entrainment process and aims to demonstrate the usefulness of such an approach within the framework of cognitive performance improvements. In the introductory part the theories regarding the neurophysiological structure and the psychological processing of the cognitive system are discussed, for each of their components that are considered to be relevant for this research. The hypothesis states that the stimulation with binaural beats and stroboscopic light, synchronized at 10.2 Hz frequency, will produce a positive change in cognition. The research variables are the cognitive performance (the dependent variable) and the brainwave entrainment (the independent variable). The brainwave entrainment program consists in the synchronized application of Alpha binaural beats and stroboscopic light, at a 10.2 Hz frequency, in a 30 minutes long session. The difference was made by the stroop effect based exercise that was used as a frame. There were 60 participants, divided into two independent samples. The two independent samples t test for the means differences was used in the statistical analysis. The obtained results by evaluations and by statistics confirmed this research's hypothesis, stating that the stimulation with binaural beats and stroboscopic light, synchronized at 10.2 Hz frequency, will produce a positive change in cognition.
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.
As the ancient cultures believed that sound waves of different frequency and beats could induce a state of meditation. Ancient Hindus and Yogis believed that specific kind of sound waves can induce relaxing effects. I found the best binaurial beat app BINAURAL BEATS - MEDITATION & RELAXATION - Apps on Google Play as it is designed to provide you with the best meditation, deep sleep, stress relief, healing and sleep sounds.
"Given the popularity and effectiveness of meditation as a means of alleviating stress and maintaining good health, there is a pressing need for a rigorous investigation of how it affects brain function," says Professor Jim Lagopoulos of Sydney University, Australia. Lagopoulos is the principal investigator of a joint study between his university and researchers from the Norwegian University of Science and Technology (NTNU) on changes in electrical brain activity during nondirective meditation.
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.

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.

, that is, the average of the two frequencies. It can be noted that every second burst in the modulation pattern is inverted. Each peak is replaced by a trough and vice versa. However, because the human ear is not sensitive to the phase of a sound, only its amplitude or intensity, only the magnitude of the envelope is heard. Therefore, subjectively, the frequency of the envelope seems to have twice the frequency of the modulating cosine, which means the audible beat frequency is:[5]

So to summarize their claim, they're saying that entrainment means that a binaural beat will cause your brain's electroencephalogram to match the pattern of the phantom beat. Well, if it did, entrainment certainly doesn't apply and would not be part of the equation, so we can scratch that off the list. But it doesn't make the claimed observation wrong. We do know that certain electroencephalogram waveforms are often associated with certain kinds of activity. For example, physical activity or REM sleep often produces an electroencephalogram with a sine wave of between 4 and 8 Hz, which we term a theta pattern. Waking relaxation with eyes closed often produces a pattern from 8 to 12 Hz, which is called an alpha pattern. There are only a few characterized patterns, and pretty general descriptions of what kinds of activities go with them. The claim made by the binaural beat sellers depends on much more granular and specific matches. For example, the claim that a binaural beat with a frequency of X produces the same effect in your brain as Vicodin is wholly implausible. Such claims presume that we know the exact frequency of the electroencephalogram in each of these desired conditions, and the fact is that brain waves don't work that way. It is wholly and absolutely implausible to say that desired brain condition X will occur if we get your EEG to read exactly X Hz.