  We consider the possibility that most of the reflection component, observed
in the hard X-ray spectra of Seyfert galaxies, could be formed on an extended
medium, at large distance from the central source of primary radiation (e.g. on
a torus). Then, the reflector cannot respond to the rapid fluctuations of the
primary source. The observed reflected flux is controlled by the time-averaged
primary spectrum rather than the instantaneous (observed) one. We show that
this effect strongly influences the spectral fit parameters derived under the
assumption of a reflection component consistent with the primary radiation. We
find that a pivoting primary power-law spectrum with a nearly constant
Comptonised luminosity may account for the reported correlation between the
reflection amplitude R and the spectral index Gamma, and simultaneously
produces an iron line EW that is nearly independent of Gamma. We emphasize the
effects of the modelling of the primary component on the determination of the
reflection amplitude, and show that in NGC 5548, when these effects are taken
into account, the RXTE data are consistent with the reflection features being
produced mainly at large distance from the central source.
