The main input to SPECTRUM has been changed to allow a more flexible definition of some of the many options and to enable the elements of the code to be used in a more versatile way. ... The strict formatting of these files makes them unintelligible and the addition of new data inputs, options, etc., difficult. For example the mode of operation currently depends on the sign of certain data inputs! ... For the time being, both old and new style input will be recognised. ...