  We describe theoretical and practical aspects of spin-echo modulated
small-angle neutron scattering (SEMSANS) as well as the potential combination
with SANS. Based on the preliminary technical designs of SKADI (a SANS
instrument proposed for the European Spallation Source) and a SEMSANS add-on,
we assess the practicability, feasibility and scientific merit of a combined
SANS and SEMSANS setup by calculating tentative SANS and SEMSANS results for
soft matter, geology and advanced material samples that have been previously
studied by scattering methods. We conclude that lengths from 1 nm up to 0.01 mm
can be observed simultaneously in a single measurement. Thus, the combination
of SANS and SEMSANS instrument is suited for the simultaneous observation of a
wide range of length scales, e.g. for time-resolved studies of kinetic
processes in complex multiscale systems.
