  We constrain the emission mechanisms responsible for the prodigious
electromagnetic output generated by active galactic nuclei (AGN) and their host
galaxies with a novel state-of-the-art AGN radio- to-X-ray spectral energy
distribution model fitting code (ARXSED). ARXSED combines multiple components
to fit the spectral energy distributions (SEDs) of AGN and their host galaxies.
Emission components include radio structures such as lobes and jets, infrared
emission from the AGN torus, visible-to-X-ray emission from the accretion disk,
and radio-to-ultraviolet emission from the host galaxy. Applying ARXSED to the
radio SEDs of 20 3CRR quasars at 1 < z < 2 verifies the need for more than a
simple power law when compact radio structures are present. The non-thermal
emission contributes 91%-57% of the observed-frame 1.25mm to 850{\mu}m flux,
and this component must be accounted for when using these wavelengths to
estimate star-formation properties. We predict the presence of strong
radio-linked X-ray emission in more than half the sample sources. ARXSED
estimates median (and the associated first and third quartile ranges) BH mass
of $2.9_{1.7}^{6.0} \times 10^9~\rm M_{\odot}$, logarithm of Eddington ratio of
$ -1.0_{-1.2}^{-0.6} $, and spin of $ 0.98_{0.94}^{0.99} $ for our sample. The
inferred AGN torus and accretion disk parameters agree with those estimated
from spectroscopic analyses of similar samples in the literature. We present
the median intrinsic SED of the luminous radio-loud quasars at 1 < z < 2 ; this
SED represents a significant improvement in the way each component is modeled.
