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Results obtained from an X-ray spectral survey of nearby Seyfert galaxiesusing XMM--Newton are reported. The sample was optically selected, welldefined, complete in B mag, and distance limited: it consists of the nearest(D<22 Mpc) 27 Seyfert galaxies (9 of type 1, 18 of type 2) taken from the Ho etal. (1997) sample. This is one of the largest atlases of hard X-ray spectra oflow-L active galaxies ever assembled. All nuclear sources except two Sey 2s aredetected between 2-10 keV, half for the first time ever, and average spectraare obtained for all of them. Nuclear luminosities reach values down to 10**38erg/s. The shape of the distribution of X-ray parameters is affected by thepresence of Compton-thick objects (> 30% among type 2s). The latter have beenidentified either directly from their intense FeK line and flat X-ray spectra,or indirectly with flux diagnostic diagrams which use isotropic indicators.After taking into account these highly absorbed sources, we find that (i) theintrinsic X-ray spectral properties (i.e., spectral shapes and luminositiesabove 2 keV) are consistent between type 1 and type 2 Sey, as expected from``unified models'', (ii) Sey galaxies as a whole are distributed fairlycontinuously over the entire range of Nh, between 10**20 and 10**25 cm**-2, and(iii) while Sey 1s tend to have lower Nh and Sey 2s tend to have the highest,we find 30% and 10% exceptions, respectively. Overall the sample wellrepresents the average intrinsic X-ray spectral properties of nearby AGN,including a proper estimate of the distribution of their absorbing columns.Finally, we conclude that, with the exception of a few cases, the present studyagrees with predictions of unified models of Sey galaxies, and extends theirvalidity down to very low luminosities.Comment: 23 pages, 4 tables, 4 figures, 2 Appendices with 27 source spectra  and notes, to be published in the Astronomy & Astrophysics Journa

X-ray spectral survey with XMM–Newton of a complete sample of nearby Seyfert galaxies