As you can see there is no eye in this diagram or anything that even looks vaguely like an eye. This is why several forms of equalization are necessary including Tx equalization, Rx equalization and ...

Digital Signal Processing (DSP): The manipulation of signals after conversion into a digital format, utilising algorithms to enhance or modify audio and other types of data.

The graph below shows the total number of publications each year in Audio Signal Processing and Equalization Techniques. References [1] Sparse Graphic Equalizer Design .