  Starting from a sample of SDSS quasars appearing also in the 2MASS survey, we
study the continuum properties of about 1000 objects observed in 8 bands, from
NIR to UV. We construct the mean spectral energy distribution (SED) and compare
and contrast the continua of radio loud (RLQ) and radio quiet (RQQ) objects.
The SEDs of the two populations are significantly different in the sense that
RLQs are redder, with power law spectral indices <alpha(RLQ)>=-0.55+/-0.04 and
<alpha(RQQ)>=-0.31+/-0.01 in the spectral range between 10^14.5 and 10^15.35
Hz. This difference is discussed in terms of different extinctions, different
disc temperatures, or slopes of the non-thermal component.
