Recreating high frequencies in dull-sounding music
However, it is possible to synthesize artificial high frequencies into music. This makes the sound image a little bit more "open". However, you need to be careful with classical music, as added content doesn't always work with it. The technique works better in pop music.
There is a "Before" and an "After" sequence in the video clip. You can see more moving green bars at the right end of the spectrum in the "After" part.
Tape-recorder playback head azimuth
If a tape is digitized with a playback head that has an azimuth error, it is not possible to correct this later. We adjust each tape side azimuth separately.
Below are two different visualizations of the same audio clip. The first is a spectrum analyzer display. Low frequencies are at the left, high frequencies on the right. You will notice more green bars at the right hand side of the window in the "After" section, as the azimuth has been adjusted to optimum.