Al nailed it dead on. Most solid state amps will not have a problem. Many tube amps have a 4 ohm tap and have zero problems driving a non capacitive load. If you can get a frequency and phase chart, you will see rises and drops in the phase angles, the rises are inductive, tube amps don't mind these, the drop in phase angles are capacitive loads. When you have a steep phase angle, especially in the bass frequencies, most tube amps, just can't handle that. Try to get a copy of the frequency and phase curves for both the Harbeths and the VA Mozart, your questions will be quickly answered.
