Don't worry about current and voltage. Look for your target watts per channel into 8 ohms. Then see what the power is at 4 ohm, and, if given, 2 ohm loads. If the power increases considerably with decreasing loading, then the amp is powerful enough to drive the speakers regardless of how much current is put out or what the voltage is. What's important is how much in reserve the amp has rather than a given current rating at only one load point - which is worthless. You can get trapped if you go by the marketing term "high current".