  The lamp-post geometry is often used to model X-ray data of accreting black
holes. Despite its simple assumptions, it has proven to be powerful in
inferring fundamental black hole properties such as the spin. Early results of
X-ray reverberations showed support for such a simple picture, though
wind-reverberation models have also been shown to explain the observed delays.
Here, we analyze new and old XMM-Newton observations of the variable Seyfert-1
galaxy NGC 5506 to test these models. The source shows an emission line feature
around 6.7 keV that is delayed relative to harder and softer energy bands. The
spectral feature can be modeled with either a weakly relativistic disk line or
by scattering in distant material. By modeling both the spectral and timing
signatures, we find that the reflection fraction needed to explain the lags is
larger than observed in the time-averaged spectrum, ruling out both a static
lamp-post and simple wind reverberation models.
