Disclaimer:
This will possibly read like an advertisement but I have nothing to do with the company, I do not get kickbacks or advantage in any way from them. My only contact with them is as a customer.
Mindfield's MindMachine
A couple of years back I found online a site that offered a method for using binaural beats for brainwave entrainment. I have been using it irregularly since, mainly because I lacked a focus of what to be using it for. I figured there couldn't be anything wrong with bringing both sides of my mind into tune, but I've long suspected there would be a real use for the technology.

More recently, from my studies & this site, I am beginning to get an idea of just how useful it might be in assisting me to open out my perceptions & to get my mind/being working the way they should be.

With this system, you can make your own sessions. They provide pre-configured sessions that can give pointers on how to achieve certain things, (such as creativity, learning or relaxation sessions) but most importantly, you can make your own sessions to do exactly what you wish.

The method used is basically to make a graph of the frequencies you want. These work just fine in Synchronised mode, but there are also Difference & Complex modes to play with.

How does it work? The system is a set of glasses, a little like sunglasses except you can't see through them, with LED's on the inside. The program generates signals that flash the LED's to each eye at the required frequencies. Also, it generates the more standard tones, separated by the frequency you've set for the session, so sound is added to the session.
(The ear can't hear below 20Hz, so to get (say) 3Hz, it feeds (say) 30Hx to one ear & 33Hz to the other. The brain follows the difference between the two, so the entrainment is to 3Hz)
This combination of sight & sound is very powerful.

So, you make or open your session, don the headphones & glasses, get comfortable & close your eyes.
(Note: you do NOT have your eyes open for this. Not only does it work better with eyes closed but these are Laser devices - low powered to be sure, but I wouldn't want even low powered lasers directly on my rods & cones)

The best part about the system is you can overlay (or underlay so it's almost inaudible) both music & voice tracks on the binaural tones. That is, you can use meditational music to help create your mood, PLUS add your own voice giving you instructions on what to do once you're in the level for which you've programmed the session.

This can also be used for learning. Record the lesson or download WAV or MP3 format & set up a session in Theta or even Delta, & you have a system better than sleep learning.

If you download a program like Audacity (free sound recorder) you can play your session through it, record it & save it as WAV or MP3 etc & copy it to a portable device for playback. So, you could make a session to put you into Alpha (good for concentration & learning) and go to the library & run the session while studying. Or run a session good for calming & destressing while going through (or before or after) some stress situation.

To investigate for yourself, visit: MindField

IMHO, this is a better & MUCH cheaper system for holosync than any of the 'pre-prepared' systems out there. It takes a little study to work out what effects are generated by the various levels & shapes of graphs, but it is soon repaid.