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Dan Driscoll · 04-17-2007, 10:12 AM

Electricity always follows the path of least resistance or impedance. A speaker is typically 8 ohms impedance, while skin is typically millions of ohms, even over a distance of just 1 inch. If you lick your skin the resistance drops to 10s of thousands of ohms, but then the current is flowing through the saliva on the surface of your skin, not through the skin.

Current by itself is not enough to complete a circuit, it requires a sufficiently high voltage to overcome the impedance of the circuit before it can be completed and current can flow. The greater the impedance, the greater the voltage required to complete the circuit. Modern home audio amplifiers are current sources, not voltage sources. They typically won't generate enough voltage to overcome the impedance of a human body and push a current through that body.

There are exceptions, of course. If you are wet and the amplifier protection circuit has failed, if you are bleeding (salt is a conductor) or wearing chain mail, you might be at risk of getting shocked. No doubt there are other scenarios that would put someone at risk, but in general the danger of getting shocked by a properly functioning modern home audio amplifier is pretty minor.

Also keep in mind that groups like Underwriters Laboratories (UL) and other safety organizations test and certify these amps before they come on the market. They are testing for exactly these types of dangers and many others.

04-17-2007, 10:12 AM	#9 of 27
Dan Driscoll Member Location: SF Bay Area Join Date: Aug 2000 Local Time: 02:36 AM Local Date: 12-02-2008 Posts: 804	Re: are banana connectors dangerous? Electricity always follows the path of least resistance or impedance. A speaker is typically 8 ohms impedance, while skin is typically millions of ohms, even over a distance of just 1 inch. If you lick your skin the resistance drops to 10s of thousands of ohms, but then the current is flowing through the saliva on the surface of your skin, not through the skin. Current by itself is not enough to complete a circuit, it requires a sufficiently high voltage to overcome the impedance of the circuit before it can be completed and current can flow. The greater the impedance, the greater the voltage required to complete the circuit. Modern home audio amplifiers are current sources, not voltage sources. They typically won't generate enough voltage to overcome the impedance of a human body and push a current through that body. There are exceptions, of course. If you are wet and the amplifier protection circuit has failed, if you are bleeding (salt is a conductor) or wearing chain mail, you might be at risk of getting shocked. No doubt there are other scenarios that would put someone at risk, but in general the danger of getting shocked by a properly functioning modern home audio amplifier is pretty minor. Also keep in mind that groups like Underwriters Laboratories (UL) and other safety organizations test and certify these amps before they come on the market. They are testing for exactly these types of dangers and many others. *Dan* "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." --Benjamin Franklin Last edited by Dan Driscoll : 04-17-2007 at 10:16 AM.