What Determines The Amount Of "Current" In An Amp?

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300 wpc amp at 8 ohms plays 4 ohms at 450 wpc

300 wpc amp at 8 ohms plays 4 ohms at 600 wpc

Does one of the above amps necessarily have more current than the other? If an amp doubles with each halving of ohms, is that an indicator of its ability to deliver more current?

Is there an identifiable specification in an amp that will tell you how much current it will be able to deliver?

The notorious Apogee Scintilla and Infinity Kappa 9 are two speakers that dip to amp-killing low ohms. What specification in and amp do you look for in its ability to drive a speaker like these. Is it current or wpc you would be looking for in a speaker like these?
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Thanks Viridian.

In the very big amps of old, they boasted large power supplies. Is it necessary for Class D amps to have a large power supply to deliver continuous high current into low ohms?
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Yes Bill, but can Class D amps deliver high sustained current into low ohms?
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