**Frequency Sampling**: A graphic equalizer can be seen as a simple digital filter which is redesigned each time the equalization settings change. When looked at this way, the obvious method for creating a graphic equalizer is to incorporate a filter design routine into your digital device, and change the desired frequency response Hd(ω) according to the equalization levels. Since frequency sampling design is as simple as an [inverse discrete fourier transform (IDFT)](http://en.wikipedia.org/wiki/Discrete_Fourier_transform) of the desired filter curve, it is entirely possible to implement this on inexpensive hardware.The advantage to this approach is that it is relatively easy to understand and implement. Only one filter is required at any given time, so it uses memory effectively. Unfortunately, since a complex filter design algorithm is not feasible on inexpensive hardware, there will undoubtedly be ripple and [Gibbs phenomena](http://en.wikipedia.org/wiki/Gibbs_phenomenon) from the IDFT. Reducing this ripple will require filters of somewhat extreme length. More importantly, because the low frequency bands have so few points relative to the high frequency bands, the response in these regions will always be relatively poorer.