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Amps, Cables and Current: A Question

Hi folks. I have a few questions I'm wondering if you can help me with....

1. I've seen some amps, such as the Odyssey Monos, that list peak current capabilities around 65 amps. How is it possible to deliver that kind of current when the unit is connected to a wall outlet that is fed from a 15amp circuit?

2. I've been having a email dialogue with the folks at Audience. I'm still confused by their response. According to them, "the Audience power cords need to be thicker because they carry so much current. A power cable the same diameter as the Au24 speaker wire would be a fire hazard" because it would not be able to carry all the current coming from the wall. They continue by pointing out that the speaker wire can be thin because it carries much lower current than the powercord.

If you understand what I've said here I think you can see my confusion. If an amp like the Odyssey is putting out 65 amps of current then that far exceeds what is coming out of the wall and therefore my thin little Au24 should be melting or causing a fire or something, no?

I'm no electrical engineer, obviously. I have to be missing something. Can anyone help?
dodgealum

Showing 1 response by gs5556

gs5556
1,241 posts
 
That 65-amp currennt delivery is misleading. You wall outlets are supposed to deliver 20-amps. If you short it out with a piece of copper, you could get as much as 10,000 amps short-circuit current. The 65-amp "peak current" is the same thing - what it's capable of producing under short-circuit conditions, or the reservoir capacity of the power supply.

The amplifier current is determined solely by the speaker load. (See jeffreybehr's post). Current can only flow through a resistive load, and the value of the resistance determines the current. But if you short the speaker wires together, you will probably get that 65-amp current - blowing all sorts of transistors and electrical components, as well as melting the speaker wire.

Just goes to show that some manufacturers, just like magicians, try to divert your attention from sonic performance by waving around big electrical performance numbers.
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