For example, exercise and perusing a goal very ambitiously are both types of stress, except they ultimately benefit the body. Areas of the brain, including the hippocampus, amygdala and prefrontal cortex can pick up on positive stressful experiences and cause “stress-induced structural remodeling” of the brain, which means you experience alterations in behavioral and physiological responses to these positive events. The result is that in the future you’re better able to handle similar situations because you learn from them, associate them with a reward and stop perceiving them as threatening.

The effects are strongest while you are listening to the tones because your brainwaves are synchronized and tuned into the frequency range you desire at that time.  After you've stopped listening the effects can still linger for a while afterwards.  The timescale will vary from person to person and be affected by what you do after you've stopped listening.

Social interaction is your body’s most evolved and surefire strategy for regulating the nervous system. Talking face-to-face with a relaxed and caring listener can help you quickly calm down and release tension. Although you can’€™t always have a pal to lean on in the middle of a stressful situation, maintaining a network of close relationships is vital for your mental health. Between sensory-based stress relief and good listeners, you’ll have your bases covered.
Different people have different requirements when it comes to frequency changes in the music and it's quite impossible for us to anticipate them all. We would need to produce so many different variants of all our music productions that it would be impractical to manage and confusing for our customers. For example, if we were to start raising the frequency from theta up to alpha between the 50-60 minute mark of a piece of music, this would be useless to someone who used the music for a guided meditation that was only 45 minutes long. In the early stages of the development of our brainwave entrainment music we had so many different requests from different people that we could only opt for the simplest solution, which is to use a consistent frequency throughout. It might not be the absolute "perfect ideal", but this is still a very effective technique and the feedback we've received on our brainwave entrainment music has always been exceptionally positive.
On the other hand, if you’re a person who generally has their life together, and who is somewhat successful in your current coping strategies, even if they’re not perfect, then a little bit of additional quiet and relaxation may not seem so dramatic to you as it does to that burned out person. It will feel good, but the degree of difference between that and your normal way of life will not seem so extreme to you as it will to the burned out person. It is a relative experience.

If brainwave entrainment leaves you with unwanted side-effects (see below) or discomfort, you’re probably encouraging a range of brainwaves that are already excessive in some area of your brain. The way around this is to get a brain map to see what your brain’s strengths and weaknesses are, and see what (if any) brainwaves could use some encouragement.