A limiter is essentially a brick wall level-wise, allowing the signal to get only to a certain point and little more beyond. Think of it as doing the same thing as a governor that's sometimes used on 18-wheel trucks owned by a trucking company to make sure that they're not driven beyond the speed limit. Once you hit 55 mph (or whatever the speed limit in your state is ), no matter how much more you press the gas pedal, the truck won't go any faster. The same theoretically occurs with a limiter. Once you hit the predetermined level, no matter how much you try to go beyond it, the level pretty much stays the same.