The invention relates to phosphor-conversion (PC) sources of white light, which are composed of at least two groups of emitters, such as blue electroluminescent light-emitting diodes (LEDs) and wide-band (WB) or narrow-band (NB) phosphors that partially absorb and convert the flux generated by the LEDs to other wavelengths, and to improving the quality of the white light emitted by such light sources. In particular, embodiments of the present invention describe new 3-4 component combinations of peak wavelengths and bandwidths for white PC LEDs with partial conversion. These combinations are used to provide spectral power distributions that enable lighting with a considerable portion of a high number of spectrophotometrically calibrated colors rendered almost indistinguishably from a blackbody radiator or daylight illuminant, and which differ from distributions optimized using standard color-rendering assessment procedures based on a small number of test samples.