There are differences between high (over 18 hertz), mid (15 to 18 hertz), and low range beta states (12 to 15 hertz). Low beta states are more relaxed while still being focused, making this a good range for many daily work related tasks like balancing a checkbook, making a shopping list, or driving to a new place. However, people with attention deficit disorder lack the mental focus for doing these types of activities, and studies have found people with ADD are often low in this range of beta brainwaves.
Good to hear from you and glad you got some value from the article. In total honesty I do feel that brainwave entrainment is safe, and that the big point is not to over-use it, or to push yourself too hard. You can almost think of it like an herb or nutritional supplement. You don’t expect big results the day/week of taking it, and if you don’t get results, you don’t keep taking more. You take it in regular safe doses over a recommended period of time and let it synergistically work its magic. Generally I think you are safe to listen to the audio you made, I just recommend taking it gradually with gamma in particular. Listen for just 10-15 minutes at first and see how your brain handles it. If it doesn’t produce any unwanted feelings then jump right in. But even then I recommend only listening once per day, and taking one day off per week.

That all said, we are all different and have our own different limits. So I generally advise that you just be aware of how you are feeling, and if you feel like you are getting a bit fatigued from it, it’s probably time to stop or at least take a break. When listening over long extended periods, I recommend that you keep yourself well-hydrated. Your brain needs a good supply of water to function well, especially if you are studying hard and increasing your brainwave electrical activity.
3) God Consciousness from Ennora. Wow - quite a name, no? Hmm - well I don't know if I felt God, but I certainly felt something ... and at the time of writing, they have got a massive sale on, with downloads costing $11 (rather than $25), so you'd be mad not to leap at this if you're the spiritual type. This isn't the only reason to choose Ennora, however - this recording has got brilliant, soothing rain sounds, it works, and it certainly gave me the advertised "everything will seem perfect". 30 minutes long again. Good stuff, perhaps not one for the atheists though :)
Until NeuralSync™, brainwave entrainment involved inferior linear, single or sequential protocols - such as binaural beats or isochronic tones - that were natively restricted in their ability to affect the natural complex dynamics of the brain. But now, NeuralSync™ significantly improves entrainment by incorporating EIGHT SEPARATE BUT SYNERGISTICALLY-INTERACTIVE DIMENSIONS into a dynamic and cohesive process powerful enough to compel the brain to produce whole-brain synchronization for intense effect. Incredibly superior to binaural beats or isochronic tones, NeuralSync offers an entrainment experience beyond anything you've used before.
Entrainment is a term originally derived from complex systems theory, and denotes the way that two or more independent, autonomous oscillators with differing rhythms or frequencies, when situated in a context and at a proximity where they can interact for long enough, influence each other mutually, to a degree dependent on coupling force, such that they adjust until both oscillate with the same frequency. Examples include the mechanical entrainment or cyclic synchronization of two electric clothes dryers placed in close proximity, and the biological entrainment evident in the synchronized illumination of fireflies.[13]