 Only a few weeks later this formulation was changed to 'symphonic works in one or more movements, presented as an apotheosis of the lyrical genius of Schubert'; it was also suggested, though not stipulated, that there could be non-symphonic works, as long as these were sets of variations on Schubert themes, but all works had to be for orchestra.Later still, a further revision of the rules stated that 'the compositions, apart from faultless formal structure, must be marked by the predominance of a vigorous melodic content, and the number of instruments employed must not substantially exceed the measure established by the classical orchestras of Schubert's time'.The contest was to be judged in two stages.