We propose a hybrid inversion analysis (hia) technique aimed at incorporating earthquakes from different seismogenic sources in one single inversion scheme. The application of this technique provides estimations of the source, path, and site effects at 23 strong-motion stations in El Salvador, Central America. The strong-motion dataset comprises 404 triaxial accelerograms corresponding to 63 subduction and upper-crustal earthquakes with MS magnitudes between 3.0 and 7.8. Application of the hia technique reveals: (1) good matching of the estimated source spectra with those derived from the ω2 point source model; (2) rapid and low attenuation patterns characterizing the upper-crustal volcanic belt and subduction zone, respectively; and (3) soil transfer functions characterized by amplification ratios larger than those derived from spectral ratio techniques by a factor of two. Reference- site-dependent techniques yield similar soil transfer functions at all stations, whereas the horizontal-to-vertical spectral ratio technique yields similar results at sites characterized by clearly predominant peaks.