I am building a replacement circuit for an existing kiosk because the audio chip the kiosk originally used is no longer available. The original audio circuit used a stereo amplifier but only used the Right output of the Computers audio into one channel of the amp. The other channel was not used and had the input shorted to ground. What I would like to do is combine the two channels of the PC speaker output into the input of a TDA2005 wired for Mono.
The attached schematic kinda shows what I have in mind. The Volume Control pot is an existing component in the kiosk and is wired as shown. (Have no idea why they didn't tie the bottom of the pot to ground). It looks like from the data sheet the input impeadance of the TDA2005 is 70K at 1kHz. I really have no idea what the output impediance of the Speaker out of a typical PC audio board is, 600ohms?
Looking for ideas on how best to utilize the existing volume pot without rewiring it and resistor values for my combiner circuit. Thanks...
The attached schematic kinda shows what I have in mind. The Volume Control pot is an existing component in the kiosk and is wired as shown. (Have no idea why they didn't tie the bottom of the pot to ground). It looks like from the data sheet the input impeadance of the TDA2005 is 70K at 1kHz. I really have no idea what the output impediance of the Speaker out of a typical PC audio board is, 600ohms?
Looking for ideas on how best to utilize the existing volume pot without rewiring it and resistor values for my combiner circuit. Thanks...
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