Whenever you come across something that seems like it could be a quack treatment, or there are varying accounts of its success or such:
1. Do Not Panic.
2. Go To Your Computer.
3. Type
http://www.rationalwiki.com Into your Internet Browser of Choice.
Rational Wiki's article on Binaural Beats. Basically, they do nothing.
And, for reference,
Rational Wiki's article on Chiropractic. Essentially:
1. Chiropractic has some real benefits for things like lower and central back pain. These benefits are often the same as those you'd get from massage or physical therapy (or even Aleve or Tylenol), and usually cost as much as or more than other treatments. (That being said, different treatments work for different people, so if you're happy with your chiropractor for lower back pain, hey, it's your money.)
2. Chiropractic has absolutely no benefits for anything not within a few inches of your spine. This includes your limbs, your cranium, and your other organs. Chiropractic therapy often claims to treat these things. It does not.
3. Some chiropractors recognize that they are essentially a variation on massage, and that's cool. Many more chiropractors ascribe to "subluxation theory," which is completely made up.