Amplifiers: High Current? High Voltage?

Peter, you are correct. Most amps are designed to act as voltage sources. An amp designed to be a current source is called a transconductance amp and their use is limited because they don't work well with most conventional 2 and 3 way speaker designs due to the design of most crossover networks. Nelson Pass does make one that is intended for single speaker systems such as Lowther based systems.

First Watt article

Gs5556, I don't follow your logic in explaining output power in terms of transfromer ratings. Yes, there is some relationship there, but not as you described. The VA rating on a transformer tells you how much power it can consistently deliver without overheating. The transformer does not choke off the current as you described in your second example (only 8 watts because only one amp can flow to the speaker). It is true that the amp has a maximum voltage that it can produce that is limited by the secondary voltage of the power transformer, but there is no "current resevoir" determined by the transformer.

The current resevoir consists of capacitors in the power supply. A power amp with a large capacitor bank can deliver huge amounts of current for brief periods of time that far exceed the current rating of the transformer secondary. The amp will try to maintain the requested voltage and only starts to dip when it can't deliver the current demanded by the load at that voltage, and even though the dcr of the transformer secondary does play into the complete analysis, the limiting factor is not the VA rating of the transformer.

That is a bit simplified but the basics of the situation.

the difference between regular amplifiers and high current amplifiers, is that, regular amplifiers us more voltage in the equation then current (which is like 50volts times 2amps= 100watts when you could use 10volts times 10amps to get the same power

"Regular" amplifiers don't use more voltage in the equation. All voltage amplifiers, which is what almost all amps are, whether or not they are capable of producing high currents , try to maintain a constant voltage out for a given voltage in. The amount of current that flows will be the voltage divided by the impedance, and the impedance is whatever it is. So called "high current" amps are the ones that have the ability to deliver more current if the impedance dips real low, but don't somehow magically push more current through the speaker than one with less reserves.