  We have studied the average 3-200 keV spectra of Seyfert galaxies of type 1
and 2, using data obtained with BeppoSAX. The average Seyfert 1 spectrum is
well-fitted by a power law continuum with photon spectral index Gamma~1.9, a
Compton reflection component R~0.6-1 (depending on the inclination angle
between the line of sight and the reflecting material) and a high-energy cutoff
at around 200 keV; there is also an iron line at 6.4 keV characterized by an
equivalent width of 120 eV. Seyfert 2's on the other hand show stronger neutral
absorption (NH=3-4 x 10^{22} atoms cm-2) as expected but are also characterized
by an X-ray power law which is substantially harder (Gamma~1.75) and with a
cut-off at lower energies (E_c~130 keV); the iron line parameters are instead
substantially similar to those measured in type 1 objects. There are only two
possible solutions to this problem: to assume more reflection in Seyfert 2
galaxies than observed in Seyfert 1 or more complex absorption than estimated
in the first instance. The first possibility is ruled out by the Seyfert 2 to
Seyfert 1 ratio while the second provides an average Seyfert 2 intrinsic
spectrum very similar to that of the Seyfert 1. The extra absorber is likely an
artifact due to summing spectra with different amounts of absorption, althought
we cannot exclude its presence in at least some individual sources. Our result
argues strongly for a very similar central engine in both type of galaxies as
expected under the unified theory.
