  We present the status of the development of a dedicated high density
ultra-cold neutron (UCN) source dedicated to the gravitational spectrometer
GRANIT. The source employs superthermal conversion of cold neutrons to UCN in
superfluid helium. Tests have shown that UCN produced inside the liquid can be
extracted into vacuum. Furthermore a dedicated neutron selection channel was
tested to maintain high initial density and extract only neutrons with a
vertical velocity component 20 cm/s for the spectrometer. This new source would
have a phase-space density of 0.18 cm-3(m/s)-3 for the spectrometer.
