Binaural beats are delivered using stereo headphones. They work by playing differing frequencies into each ear. The brain tries to make sense of them as one sound, and by doing so, modifies it's own frequency. Binaurals can be used to change the state of arousal in the brain - from high energy focus, through deep relaxation to very deep delta sleep.
The internet is jam-packed full of people selling different products that incorporate binaural beats. Some companies make some pretty tall claims as to the efficacy of their products - they can turn you into a millionaire, they can make you live longer, they can help you cure disease etc...
Let's put these into perspective. Binaural beats change the frequencies of the brain. They can help you achieve a desired state of focus. They can help you enter a state of hypnotism, so suggestions for change can be fed to you. You get great sleep on them, and amazing deep states of meditation. They are not a panacea. If you are taking medication for something like depression or cancer, don't stop. If you suffer from strobe-induced epilepsy, consult your doctor before using them. What you do, is your trip entirely, and don't hold me responsible if you are sucked into any health "cures" or "instant wealth" scams using this technology.
Now we've done a little bit of expectation management, there are a lot of products on the market. There are two main approaches:
Passive: These products are generally suggestions that are fed to you - either verbally, visually or subliminally. They help you to make change. Some incorporate Neuro-Linguistic Programming, Hypnotism, Subliminal suggestions and combinations of those. They can be very effective in changing habits like giving up smoking, biting nails, healthy eating, public speaking or phobias. All you need to do is listen.
Active: These products offer a service that is more give and take. They are generally much more expensive, and follow a set curriculum. Typically, they can involve spiritual growth, shamanic journeying, out-of-body experiences or merely scientific self-exploration.
I have been more interested in the active products - choosing to use binaural beats to deepen my state of meditation. Let's start with the cheapest and work our way up......
SBAGen: This is an open-source command line program. If you are comfortable with computer languages and are interested in brainwave experimentation, this is really good. Once you get your head around how to write the programs and run them using the machine, it's great. What's more - it's free. Get it here. You can get it for all platforms.
iPhone Apps: there are a number of iPhone/iPod Touch apps that can generate binaural beats. one of the best - Mindwave 2 - costs £2.99 on itunes. There are many more. Just do a search.
BwGEN: This is a much more user-friendly program. It comes with lots of presets for different applications. You can download the shareware version here. The better service costs. It's $40 to register and get the full version.
The above are for people interested in producing their own patterns and listening to them while plugged into their computer. I like these, becuase I like to be in charge of every aspect of my experience. Let's now see the high-end products. They are typically put on CDs. The two main competitors in this field:
The Monroe Institute (Hemi-sync): The Monroe Institute was the first to experiment with binaural beats as a means of education via the exploration of consciousness. They offer single CDs and sets that have a wide range of applications. The CDs are binaural beats with verbal instructions only. You actively follow those instructions. You are also given exercises to do your own thing with that they call 'free-flow'. The only criticism is that if you buy a CD, there is little in the way of direct support from the Monroe Institute itself. You can ask questions on the website though, and they have a growing internet community. They also offer ambitious residential programs where you can experience profound states of meditation, shamanic journeying, out-of-body experiences and evolution of consciousness. They are not cheap, but the care that has been put into the programs is great. See the Monroe Institute here.
Centerpoint (Holosync): Centerpoint offer a program that is less ambitious in it's scope, but gives more support to the home user. You subscribe with them, and get regular support via emails and telephone. My personal opinion is that their awakening course can cause undesired feelings of anxiety and stress to leak into the normal day.. This is something that is encouraged, as they say these are feelings that need to be uncovered so they can be dealt with. The CD's themselves are binaurals with rain, subliminals and ringing bells. Depending on the way you choose to work, they are either boring, or zen-like. They also offer residential courses. See centerpoint here.
Whichever way you choose, binaurals are a fantastic tool for personal growth. Speaking for myself, I now get the best sleep and the most profound states of relaxation and meditation quickly and easily.