Dave Smith Instruments SYNTHESIZERS

Hi - Im rather impatiently waiting for an Evolver coming back from
the 
US in about 4 weeks.  In the meantime, I have read almost everything
I 
can find on it.  One questions remains:

What is the Input and Output Hack?  The manual says it 'trashes the 
sound quite rudely' but what is it?  Obviously not a distortion as 
there is a separate distortion..

Thanks for any replies..

Paul
London
www.punkdisco.co.uk