The brain will entrain to its most dominant frequency the easiest. The farther you get from the dominant frequency, the harder it is to entrain. When you are excited, sleeping will be hard, if not impossible. In other words, if your dominant brainwave is high beta, it will take a long time to entrain to theta. The idea of a ramp is to try to capture the dominant frequency and lead it to the target frequency. Ramps are also used in NFB when the objective is to suppress or increase a brainwave band.

Having an EEG that can calculate dominant brainwave frequencies can significantly increase the effectiveness of your sessions. Just remember that you need the dominant frequency when you do the session, but having more information is better than guessing.

Ramps are debatable, given that the brain will eventually entrain a steady stimulus if held long enough. David Seiver's EEG experiments found that entrainment took an average of 6 minutes to show on an EEG. Ramps are, at the very least, pleasant to listen to and give the illusion that things are slowing down or speeding up. Unless it is a very short session, I almost always use ramps.

The standard rate for a ramp is + - 1 Hz per minute. As the user adapts to using BWE, the ramps can be shorter.