The potential of a magnetically enhanced hollow cathode arc source for high rate PECVD processes has been evaluated for amorphous hydrogenated carbon film (a-C:H) deposition from acetylene precursor gas. The argon–acetylene plasma has been characterized by energy-resolved mass spectrometry revealing a large variety of dissociation and polymerization products as well as their kinetic energy distributions, which are related to the spatial distribution of ion generation. a-C:H layers have been deposited on flat substrates with rates of up to 1μm/min. Depending on the deposition conditions, polymeric, graphitic, and diamond-like carbon films with a maximum nanoindentation hardness of 18.2GPa have been produced and analyzed by Raman spectroscopy, scanning electron microscopy, elastic recoil detection analysis and Rutherford backscattering spectrometry.