Dick PA0SE,

 

It was not until recently that I found out about the extent of "mixer control" placement(s) in a sound card.  There are analogue and digital mixers.  The MIC-IN, LINE-IN and CD-IN have inputs split to feed an A/D converter as well as an anlogue mixer going to the master volume control and LINE-OUT (also an internal power amplifier and speaker out on some sound cards, newer types have speaker matters external to the PC).

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I trust my text explanations are useful.  I do not have a block diagram at hand of a sound card, but if another reader does, and can scan it, then I'm sure it would be a good way to add to the information.

 

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