I just found this recenty and have heard some really good stuff about it,I'm going to experiment with it and see what I can come up with.

Box X is a method of combining 2 different voices (actually 4, thus
the "box") and entraining the brain using binaural AND monaural
beats. Harmonic (and half-harmonic) BoxX involves focusing on a
specific frequency and multiples of it. Harmonic Box X is an
incredibly effective way to entrain the brain. So far I've found that
it is at least 3 times as effective for me. The deep meditation ones
I made are very fast and effortless in execution. I might upload one
to the files directory if anyone is interested.

This is a quick way to make a harmonic box X (described by James Mann
in Awakening Mind I) in bwgen.

For this demo:
Take a desired binaural beat frequency of 15 (beat)
Take an audible pitch of 500 (pitch)

Step 1) Add voice 1, assign pitch and beat as above
Step 2) Add voice 2
Step 3) For voice 2 pitch, multiply beat by 2 and subtract from
pitch. So pitch - (beat * 2) or 500 - (15 * 2) = 470
Step 4) For voice 2 beat, multiply the voice 1 beat (15) by -1, which
would make it -15

And that's it! You got yourself a harmonic box X

The pitches are now as follows:

V1: 507.5 | 492.5
V2: 462.5 | 477.5

507.5 - 492.5 = 15
462.5 - 477.5 = -15
492.5 - 477.5 = 15 [monaural]
507.5 - 477.5 = 30 [crossover freq]
492.5 - 462.5 = 30 [crossover freq]
507.5 - 462.5 = 45 [monaural]

I've found this to be particularly effective with Schumman
frequencies, using 7.83 as the base. Can produce some interesting
effects to say the least.