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low to high impedance box

stormin norman

Dec 1, 2011
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Dec 1, 2011
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A total newbie here when it comes to figuring out a means of building a circuit that allows me to connect an electronic keyboard to a mic line input. I'm sure something maybe in the line of a DI box might be the direction I take, but isn't there a simple circuit I can build in a small project box to accomplish this?
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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I presume the keyboard has a low impedance output (and at line levels) and the mic input is a high impedance (and designed for low level signals).

The problem is the high output level rather than the impedance mismatch (low impedance output driving a high impedance input is rarely a problem per se)

You need to attenuate the output -- does the keyboard have a master volume control? What happens when you turn it almost all the way down?
 

stormin norman

Dec 1, 2011
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Dec 1, 2011
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Thanks Steve for getting back here. I am coming out of the headphone jack on the keyboard which does have it's own volume control. Maybe a better use of wording would have been to say a line output to mic level? I cover sound occasionally at a venue and when needed there is a small project box that gets used to go from a keyboard to the mic input location. Also sometimes when using an I Pod to connect into the sound board. I did have the cover off this box some time back and it looked like a small transformer and transistors were used in it's construction. If that's any help for you..?
 
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