Jancar, A. Cvachovec, F. Kopecky, Z. Matej, Z. JACoW Geneva, Switzerland A newly developed fast digital spectrometer for neutron spectroscopy is presented. A pulse shape discrimination (PSD) performance of the spectrometer has been evaluated within two experiments with different neutron energies. A modular design of the spectrometer allows a variety of measurements in mixed radiation fields. The detector signal output is connected to an analog input amplifier and split into two channels with a different gain. Each signal channel is digitized by a fast analog digital converter. The digital channels are merged into one composite channel with a higher digital resolution in a wide dynamic range of energies. The experimental measurements of secondary neutrons were carried out in the laboratory of Van de Graaff accelerator and at the Proton Therapy Center in Prague. A detector with liquid scintillator NE-213 was employed in both experiments. Secondary neutrons with maximum kinetic energy of 17 MeV were produced. In a workplace of the Proton Therapy Center, secondary neutrons were generated during the interaction of the primary proton beam of energies in the range of 100 to 200 MeV with a plastic phantom.