We describe the concept and the performances of a new tunable soft x-ray inverse photoemission (IPES) spectrometer. The instrument is based on a variable-geometry Bragg spectrograph, and it can be operated with minor modifications over a wide range of photon energies (600<hν<4000 eV). It was originally designed for IPES measurements of cerium compounds at the Ce M5(3d5/2→4f,hν=883 eV) absorption edge, where the Ce 4f IPES cross section is resonantly enhanced. Such resonant IPES (RIPES) spectra, now routinely performed by this instrument, are 10–100 times more sensitive to the Ce 4f states than conventional x-ray bremsstrahlung spectra, with a comparable energy resolution (ΔE∼600 meV). We plan to exploit the wide tunability of the spectrometer to perform RIPES measurements of other correlated materials, namely at the Cu L2,3(2p→d,hν=930 and 950 eV) edge in the high-Tc superconductors.