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I am currently building an audio amplifier. The goal is to connect the amplifier to a audio jack and the other end to a (4 ohm) speaker. I want to know the specifications of the output power (including voltages and amps) of the audio jack.

I already connected the output the oscilloscope, but got different result based on different devices (my PC was giving 1.5 volts while the phone was giving "only" 1 volt). That gives the suggestion that there is a space in what could still be as accepted on the output of the jack.

P.S. I was kind of struggling if this question is really "electrical engineering" or something else. Please don't downvote, but let me know and I will remove it here and put in whatever else is better suited.


merged by Dave Tweed Mar 22 '16 at 22:38

This question was merged with What is the voltage range of a standard headphone jack from a phone? because it is an exact duplicate of that question.

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