Why would you want to? I'm sure there is a good reason to do this, but it escapes me. The amp will run a 3-4 ohm load but not at high voltage (high volume levels) for long periods of time. Impedence matching transformers will kill dynamics, so you may not care for the result.
Keep the volume down to a reasonable level and it should play fine. Neither speaker is a tough load for that Mac.
Keep the volume down to a reasonable level and it should play fine. Neither speaker is a tough load for that Mac.