Re: Amplified audio from K3/K4


W2XJ
 

You’re over thinking this. Audio is rarely matched except for possibly long lines. The 10 K impedance of the amp will simply respond to the voltage of the K3(4) audio. 


On Nov 18, 2020, at 11:13 PM, Phil Westover <492commish@...> wrote:

I would like to drive outboard speakers with a higher audio level than the rigs can provide on their own.  In the past, I have used amplified computer speakers, but they present a lot of noise, most likely starting at their power supplies.  I want to be able to take a stereo output from the K3 (eventually a K4), run it through a small amplifier and out to mounted bookshelf speakers.  It's the impedance matching that I'm not figuring out.  There is a "line out" on my K3, but if I'm not mistaken, that needs 600 ohm load, which apparently is presented by a computer.  The audio amplifiers I'm potentially using require typical higher (much higher) input impedances in the 10k+ range.  Obviously, I can't use the speaker output from the K3 (K4).  Also, once I get my K4, I want to try and mix the audio signals into a single stereo amplifier.  I've got a circuit in mind for a passive mixer, which again requires a higher impedance input.  Any suggestions out there?

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