RCA or TS 1/4″ ins/outs for 2 channels. has enough headroom to work well with +4 dBu or -10 dBV line level signals.
For the 462, BBE based their process on a combination of dynamic equalisation and phase manipulation. To augment the high frequency enhancement of the BBE process, the Model 462 features a Lo Contour control which adds power to the bass end of the spectrum (around 50Hz). Few details are provided to explain how this works, but reading between the lines, it appears to be another form of dynamic equalisation.
Since the operating principle of the 462 is based on dynamic equalisation, the end result depends very much on the dynamics of the incoming signal. For example, used on a constant level ‘pad’ sound, the result isn’t far removed from what you’d expect when using a conventional equaliser. Conversely, a dynamically active signal such as a drum track or percussive bass line is treated in a far more positive manner. Transient details — such as snare drum beats and cymbal hits — take on extra sparkle, while more subtle sounds — such as reverb and intricate keyboard textures — seem to open up, allowing the individual sounds in a mix to shine through rather than burying each other. Similarly, the bass enhancement helps to make a bass line or bass drum sound punchy without unduly clouding what goes on between the beats.
read the complete soundonsound review: https://www.soundonsound.com/reviews/bbe-sonic-maximizer-model-462