I have no knowledge of how well the Arcam would handle a two ohm load. But I want to point out that while putting either a resistor in series or the two speakers in series will result in a functioning setup, it is not a recipe for quality sound. In either case bass damping goes out the window. And in the case of the two speakers in series, if their impedance vs. frequency curves are not identical, frequency response irregularities will result in both speakers.
Regards,
-- Al
Regards,
-- Al