For several years, an international group of scientists has been developing instrumentation and gathering experience regarding neutron Brillouin scattering. The requirements are neutrons of relatively high energy, small scattering angles, and high resolution in order to obtain data at small momentum transfer and high energy transfer. In 1988 and 1989 a number of test experiments have been performed on the four-chop-per time-of-flight spectrometer IN5 of the ILL (Grenoble) using a position-sensitive detector with time-of-flight analysis. After the first experiment on high density nitrogen gas at room temperature, the results of which have recently been published (I), IN5 has been improved considerably, mainly with respect to background scattering.