Some research suggests that the benefits from brainwave entrainment can last a lot longer, and still be seen for some time after you've stopped using it.  Study participants have still maintained improved test scores a few weeks after the stimulation had ceased.  Research on the long-term benefits has so far been minimal though, so how long the effects last is still up for debate.
In March I started using the CDs that I affectionately call “Meditation for Dummies” and am very pleased with the results so far. My blood pressure has dropped, I am sleeping better and notice that I feel much more calm and less stressed. Instead of feeling that I need to “find the time” in my schedule to meditate, I look forward to that totally relaxing half hour–that peaceful feeling of floating.
These guys behind this system are just brilliant, and I have seen many people confirming this, as they are loving the experience with this system. Actually, I went through a few groups and forums and found people saying they had a pretty great time. But since I’m not allowed to take screenshots of the forums, here is one I managed to get elsewhere:
So if you are interested in using brainwave entrainment music in your own recording, do so with the knowledge that it can only help to improve the quality of your work. But please don’t feel as though your recordings will be insufficient without it (some people do worry about this - unnecessarily). My advice is that if you ever find yourself in a situation where the music you love the most is not available with brainwave entrainment frequencies, don’t ignore your intuition and discard that music. When you find that piece of music that brings your recording to life, go with it whether it has brainwave entrainment frequencies or not. The quality and feel of the music itself are the most important factors.
When I am using equisync I feel kind of like it is “pushing me” – I guess this is the right way to say it- to achieve better results, which I really like. I fall asleep quickly, and sleep all night and even wake up before my alarm goes off. I feel noticeably calm during the workday- which is very helpful for what I do. I really like the warm feeling (my whole body gets really warm during my equisync meditation sessions) and I feel kind of like Im floating while listening. The soothing rainfall is also very nice.
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.

LEARNING OBJECTIVE • Exercise can be an effective component of a stress management program, and all types of exercise can be beneficial for stress management. Exercise programs consistent with the current recommendations to improve health can be prescribed to manage stress. Fitness professionals should recognize that it might be necessary to refer a client to a psychologist or other health care provider to help develop strategies for managing stressors that produce chronic and acute episodic stress.
Brainwave entrainment is a field of study and endeavor founded in the same physiological and psychological processes that make music, drumming, and chanting so powerful as methods for transforming the mind and spirit and aiding in healing of the body. These processes involve how the electrical energy in our brains synchronizes with sounds and visual stimuli, producing a particular brainwave frequency and its associated mental states. 
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.
EquiSync’s design is based on the 100’s of studies performed on the effectiveness of brainwave entrainment technology, and 1000’s of studies on the powerful benefits of meditation. If you are interested in better understanding the power of this technology and rapidly expanding field of research, then here is a very abbreviated bibliography, a very small sample of the studies out there:

Daniel Boone, in Kentucky, made his fortune trading ginseng, although he is remembered as a fur trader. It is reported in a book called Woodland Nuggets of Gold that George Washington wrote to Boone, "The war effort needs money, bring ginseng." American ginseng helped support the revolutionary war effort, and the most valuable cargo to leave New York by ship in that time period was in the Empress of China, which was carrying American ginseng to the Orient.
This session uses a proven technique for inducing deep relaxation, playing one frequency for two minutes, then alternating to a second after a 30-second ramp, then reversing the process. The first half of the session switches between a serotonin-boosting 10Hz and the grounding and rejuvenating 7.83Hz Schumann resonance. The second half of the session goes even deeper, alternating between the relaxing 7.83Hz and 6.3Hz, a frequency associated with releasing anger and irritability. The session ends on a chilled out 10Hz.
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