To determine if an amp is "high current" - ask the salesman to take off the cover. Look for:
- one or two metal boxes or toroids (transformers) - bigger is better;
- several cans (capacitors) - again, bigger is better;
- a dozen or so 1" squares with 3 whiskers or ovals (power transistors) mounted on the inside of an exterior surface - yet again, more is better.
All of these are required to make a "high current" transistor amplifier. Or you could just ask for a brand that’s famous for it, like Bryston.