Today, EEG machines are used for diagnosing epilepsy and sleep disorders, for determining dosages for anesthesia, and measuring the brain activity of people in comas or suffering from brain trauma. EEG machines also continue to play a role in researching and understanding brainwave entrainment and developing new and better methods for delivering the benefits of this form of brainwave modification. 
Isochronic tones work just the same in delta as they do in alpha, theta and beta and they are widely used in the brainwave entrainment community to help people sleep. Like you, I’ve also seen some websites saying they don’t work in delta, but it’s a bit like the game of Chinese Whispers, where someone makes a comment and then after it gets passed around and shared a lot the message gets distorted and appears to be a fact. I don’t know of any scientific reason why they wouldn’t work in delta. I remember some people talking about this on a brainwave entrainment forum many years ago. They were saying they found isochronic tones a bit too abrupt for using to help them sleep and they preferred binaural beats, as they thought they were a more soothing sound. That was just a personal preference shared by a couple of prominent forum members at the time and some people then took that as a fact for everyone. That’s where I think that belief originated from.
Controversies concerning the brain, mind, and consciousness have existed since the early Greek philosophers argued about the nature of the mind-body relationship, and none of these disputes has been resolved. Modern neurologists have located the mind in the brain and have said that consciousness is the result of electrochemical neurological activity. There are, however, growing observations to the contrary. There is no neuro-physiological research which conclusively shows that the higher levels of mind (intuition, insight, creativity, imagination, understanding, thought, reasoning, intent, decision, knowing, will, spirit, or soul) are located in brain tissue (Hunt, 1995). A resolution to the controversies surrounding the higher mind and consciousness and the mind-body problem in general may need to involve an epistemological shift to include extra-rational ways of knowing (de Quincey, 1994) and cannot be comprehended by neuro-chemical brain studies alone. We are in the midst of a revolution focusing on the study of consciousness (Owens, 1995). Penfield, an eminent contemporary neurophysiologist, found that the human mind continued to work in spite of the brain's reduced activity under anesthesia. Brain waves were nearly absent while the mind was just as active as in the waking state. The only difference was in the content of the conscious experience. Following Penfield's work, other researchers have reported awareness in comatose patients (Hunt, 1995) and there is a growing body of evidence which suggests that reduced cortical arousal while maintaining conscious awareness is possible (Fischer, 1971;West 1980; Delmonte, 1984; Goleman 1988; Jevning, Wallace, & Beidenbach, 1992; Wallace, 1986; Mavromatis, 1991). These states are variously referred to as meditative, trance, altered, hypnogogic, hypnotic, and twilight-learning states (Budzynski, 1986). Broadly defined, the various forms of altered states rest on the maintenance of conscious awareness in a physiologically reduced state of arousal marked by parasympathetic dominance (Mavromatis, 1991). Recent physiological studies of highly hypnotizable subjects and adept meditators indicate that maintaining awareness with reduced cortical arousal is indeed possible in selected individuals as a natural ability or as an acquired skill (Sabourin, Cutcomb, Crawford, & Pribram, 1993). More and more scientists are expressing doubts about the neurologists' brain-mind model because it fails to answer so many questions about our ordinary experiences, as well as evading our mystical and spiritual ones. The scientific evidence supporting the phenomenon of remote viewing alone is sufficient to show that mind-consciousness is not a local phenomenon (McMoneagle, 1993).  
Yoga has been shown to have similar benefits, reinforcing the “mind-body connection,” improving how people (especially women) feel about their bodies, helping with sleep and controlling anxiety. A review of over 35 clinical trials that tested the effects of regular yoga on stress levels and health found that, overall, yoga offers significant improvements in various physical and psychological health markers for the majority of people. (3)
This simple app doesn’t have tons of bells and whistles, but by being just a one-screen app it doesn’t drain your battery or interfere with other apps you might be running. The interface is straightforward and lets you input exactly what binaural beats frequency you want to achieve. This is a great app if you know exactly what you want and you don’t want anything to get in the way of that.
When we first use brainwave entrainment, we may not have anything specific in mind that will happen, but we hold a general expectation that “something” should happen. As we begin the process of entrainment we are on high alert looking for any little indication that something is happening. Pretty soon we identify some feeling or twitch or unusual perception. The moment we focus on whatever it is, the act of focusing on it magnifies the thing. Since we were already viewing the situation with an expectation that it was the entrainment that was going to produce some sort of result, we automatically associate whatever our phenomenon is with entrainment.

A more extensive study of over 100 participants who were undergoing general anesthesia for a day procedure, reported a decrease in pre-operative anxiety. The participants in this study listened to 30 minutes of binaural beats before surgery, but the researchers noted that people experiencing high levels of pre-operative anxiety could listen to binaural beats for up to 1 hour before anesthesia to reduce levels of anxiety.
As with meditation, mindful exercise requires being fully engaged in the present moment, €”paying attention to how your body feels right now, rather than your daily worries or concerns. In order to “€œturn off”€ your thoughts, focus on the sensations in your limbs and how your breathing complements your movement, instead of zoning out or staring at a TV as you exercise. If you’€™re walking or running, for example, focus on the sensation of your feet touching the ground, the rhythm of your breath, and the feeling of the wind against your face. If you are resistance training, focus on coordinating your breathing with your movements and pay attention to how your body feels as you raise and lower the weights. And when your mind wanders to other thoughts, gently return your focus to your breathing and movement.

None of our formulas contain gluten. The pure Italian wheat-based grain alcohol we use leaves all gluten behind when distilled, and comes with a gluten-free test certificate. The only other grain used in any of the formulas is Milky Oats, which is sustainably harvested and sorted in a botanical house. It is not processed with, or contaminated by, other grains.

... [9] While entrainment by binaural auditory beats in the alpha frequency has also been shown to enhance creativity, cognition, memory, and an improvement in intelligence tests and achievement tests in learning disabled boys. [10][11][12][13] The gamma-band activity has been shown to involve in a variety of functions such as attention, memory, and consciousness. Current literature suggests that entrainment by gamma beats promotes cognitive flexibility, modulates visual attention, and enhances creativity. ...

Turns out, science says there is something to needing “fresh air”—even opening a window can help get more oxygen to your brain, soothing stress. “We live so much of our lives indoors, that when stress hits, one of my go-to techniques is to get outside or open a window,” Dr. Serani says. “Taking in a nice deep breath of crisp fresh air can immediately shift your neurochemistry.” If you’re overwhelmed with work, it can seem hard to take a break; but a quick step outside is even recommended by the American Psychological Association. When you come back, you’ll be recharged and ready to take on the challenge.
In physics, entrainment is the process of two oscillating systems coming to assume the same periodic rhythm, such as is observed when two clocks slowly synchronize their ticking and tick together in harmony after some time. Pendulums also achieve this same synchronicity when swinging in close proximity to one another, a phenomenon first observed and written about in 1665 by Christiaan Huygens, a Dutch scientist.

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.
We can’t always control sources of stress in our lives, but we change how we react to them. The good news is this: The human body is actually designed to experience and handle stress, which is exactly why our bodies react to it so strongly. With some practice, we have the power to learn to use certain elements of stress to our advantage (for example, the fact that stress keeps us more alert and attentive), while better controlling other negative reactions (like digestion problems or giving in to cravings for unhealthy foods).
Most programs start at a work/life busy brain Beta frequency of twenty light flashes per second (20Hz) and slowly ramp them down to Alpha (relaxation and meditation) at 8-12 HZ, Theta (deep relaxation and dreaming) at 4-8 Hz) and Delta (dreamless deep relaxation) of .5-4Hz. We have taken measurements at Mass General with state of the art EEG equipment and have seen a slowing of the brain waves from Beta to Theta in two minutes and complete brain wave harmonization in the left, right, anterior, posterior and occipital regions of the brain.
♥ Taking the 16 HZ setting and combining it with a playlist of chilled out deadmau5 songs produces interesting effects, my right arm slowly began tingling and I eventually became rather focused on the task at hand. To be honest, although I don't go in for placebo and homeopathic remedies, the feeling I received from this combo made me feel... Alive... For the first time in a long time. It was nice.
With the binaural beats, this may be difficult to do since you need to listen to the twin frequencies and allow your brain to create a third one to bridge the gap. Ideally, you will be listening to these beats through headphones so carrying out other work may be challenge. However, with isochronic frequencies, the tone can be heard without headphones which means you can run the mp3 with a speaker and allow it to play in the background as you carry out your work. Of course, activities such as driving or operating heavy machinery should NOT be undertaken when you are listening to these tones because your attention is shared between the two tasks. Tasks like gardening or sewing or cooking can be done while your brainwave entrainment music is playing.
Theta waves are associated with ➤ Increased sense of inner peace and emotional stability ➤ Deep relaxation ➤ Improved memory ➤ Heightened intuition and inspiration ➤ Calms the chatter of your mind ➤ Increased psychic abilities and sense of spiritual connection ➤ Speed healing, improved physical healing ➤ More restful sleep ➤ Release beneficial hormones related to health and longevity ➤ Reduce mental fatigue ➤ Reduction of anxiety and stress

Some people are more resistant to brainwave entrainment than others and they may need many more sessions for the tones to start taking effect. Experts recommend that you listen to your brainwave entrainment music regularly because the positive impact is cumulative and builds as you listen to it day after day. Once you start feeling the effects, you will want to continue the sessions.
Entrainment is a phenomenon by which some external sensory stimulation synchronizes brainwaves differently than the native rhythm. The most obvious example of this is photic driving – during an EEG the subject will have a strobe light flashed before them at various frequencies. The purpose of this is to see if it will trigger seizure activity. In many normal subjects the brain wave rhythm in the occipital lobes, which is the visual part of the cortex, will match its frequency to the frequency of the strobe light. This specifically is called photic driving, but the phenomenon in general is called entrainment.
You have three Theta options. First, you can begin with the 30 minute Alpha Light Meditation, then do the 30 minute Theta Deep meditation that is in the same folder with the Alpha track. This is the most gentle way to introduce yourself to the Theta meditations, as these two tracks are designed to work with each other. This Theta track must be used after the Alpha track, because it begins with the same frequency where Alpha ends.
Really great stuff here, man. Well done! Without taking anything away from the article it would have been great to have under one “roof” similar information about hypnotherapy and subliminals. I invested quite a lot in buying binaural cd’s but after reading your material I think that for short term effects isochronic tones rather than binaurals are the technology to go for now. For longer lasting and possibly permanent effects I’m not sure whether I should go for hypnosis or subliminals (or both). An article as well written and comprehensive as yours but focusing on hypnosis vs subliminals would have completed the circle for me. The stuff I’ve read so far on binaurals vs isochronics hasn’t really done it for me. Any chance you could give it a shot?
When you play two separate frequencies in each ear, say 140 Hz and 149 Hz, the difference in frequency is 9 Hz. Your brain compensates for this difference and a third tone of 9 Hz is experienced. This will result in your brain being lowered or raised and tuned into the desired frequency. This is how binaural beats are produced. Headphones are essential for this to work.  

I have seen 1.5Hz being linked to HGH, but also 4 or 5 other frequencies as well, so it’s difficult to know what may work if any. I haven’t seen any research relating to HGH and brainwave entrainment. It’s widely believed that 40Hz is the limit for achieving a brainwave entrainment effect, which is also where many believe the gamma frequency range begins. Once you get over 40Hz into gamma your brainwave activity isn’t likely to stay in sync with it. So from a brainwave entrainment perspective, I recommend high beta frequencies for increasing energy during workouts.
The idea behind CBT is this: If you can reframe the way you think about events in your life — for example, instead of panicking over a job change you choose to embrace it, prepare as best you can and seize the opportunity to start fresh — you can literally reduce the stress you wind up feeling from the event. CBT is useful for training us to avoid internal causes of stress, such as “all-or-nothing” thinking, jumping to conclusions, pessimism, having unrealistic expectations for ourselves, always expecting the worst-case scenario, and feeling guilt or shame over events that are out of our control. (11)

Monaural beats have similarities to binaural beats, but the two separate frequencies are delivered through a pulse pattern and mixed before they reach the listeners ears, resulting in the advantage of being audible without stereo headphones. However, using stereo headphones intensifies the effectiveness of monaural beats and is recommended for the best effect. 
This extremely popular app features over 90 tones and music to help you achieve your desired state of mind. While other apps focus on sleep, memory and meditation, this app also includes programs for increasing psychic abilities, contacting spirit guides, and enhancing yoga. This subscription-based application is right for you if you’re looking for an experience specifically designed for your health, spiritual and emotional desires.

The functional role of neural oscillations is still not fully understood;[6] however they have been shown to correlate with emotional responses, motor control, and a number of cognitive functions including information transfer, perception, and memory.[7][8][9] Specifically, neural oscillations, in particular theta activity, are extensively linked to memory function, and coupling between theta and gamma activity is considered to be vital for memory functions, including episodic memory.[10][11][12]