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RE: High Current Amps?

Posted by Ralph on April 11, 2022 at 12:13:17:
I love how 'high current' means something other than the only thing it can mean, which in this case is an amp can make a certain power into a certain impedance.
Current cannot exist without voltage and vice versa. Together they are called 'Watts'.
A lot of times the 'current' advertised is actually how much current is present when the power supply is shorted and nothing to do with the output section at all, other than an extra bit of capacitance in the power supply.
For example, I've seen '80 Amps' advertised. If you give the amp the benefit of the doubt, and assume that into a 1 Ohm load it can make 80 amps, that means that into 1 Ohm it can make 6500 Watts! Power = Current (squared) X Resistance (in this case 1 Ohm). If you increase the resistance you see the power going up quite a lot. I don't know of amps that powerful- for that matter I don't know of a 6400 Watt amp either!
So that means a current value like that means something else- and that 'else' is the current when the amp's power supply is shorted. Briefly.
Let's say you need 400 Watts into a set of Maggies to really make them sing.
400 Watts = Current (squared) X 4 Ohms
solving for current we get 10 Amps. That's really not that much current as these ads I've seen go, but if you want 400 Watts into 4 Ohms that's the current.
It might be that too many manufacturers have been called on making outrageous claims that can't possibly be true. Is that why we don't hear about this so much anymore?? :)