  We present the spectral analysis system for the second-generation Energetic
X-ray Imaging Telescope Experiment (EXITE2) balloon payload. EXITE2 is an
imaging hard X-ray telescope using a coded-aperture mask and a NaI/CsI phoswich
detector operating in the energy range 20--600 keV. The instrument was flown on
a high-altitude scientific balloon from Ft. Sumner, NM on 1997 May 7-8. We
describe the details of the EXITE2 spectral analysis system, with emphasis on
those aspects peculiar to coded-aperture instruments. In particular, we have
made our analysis compatible with the standard X-ray spectral fitting package
XSPEC by generating a response matrix in the appropriate format including all
the effects of a coded-aperture system. The use of XSPEC, which may be a first
for coded-aperture data, permits great flexibility in the fitting of spectral
models. The additional effects of our phoswich system, or any other
detector-specific considerations, may be easily included as well. We test our
spectral analysis using observations of the Crab Nebula, and find that the
EXITE2 Crab spectrum is consistent with those recorded by previous instruments
operating in this energy range.
