The "cactus needle" is actually more like balsa wood.It is used in the gramophone era playback.The sound is direct to the horn.No recording possible,except of course open mike.Why wouldn't you use your VPI/Grado combo?If the VPI will spin 78RPM.The EQ of the Acetate is most likely not RIAA.I believe KAB USA has some pre-amp EQ options available.