A method to generate synthetic neutron spectra from bulk and fast ion distributions simulated by TRANSP has been developed. In this paper, synthetic data generated from fuel ion distrubutions modeled with TRANSP is compared with measured data from two neutron spectrometers with different lines of sight; TOFOR with a radial one and the MPRu with a tangential one. The information obtained from the analysis of the measured neutron spectra such as the relative intensity of the emission from different ion populations puts additional constraints on the simulation and can be used to adjust the variables in the simulation.