  We investigate the effect of localized opacity modifications on the
sound-speed profile of solar models. The sound-speed difference between the Sun
and a solar model is used to deduce the opacity correction that would be
required to bring the model into agreement with the Sun. We test this procedure
on artificial data for a pair of solar models and apply it to the solar sound
speed as inferred from inversion of LOWL observed frequencies. We show that a
solar model constructed with the appropriately modified opacity has a
sound-speed profile very similar to that of the Sun.
