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Dave Platt Dave Platt is offline
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Default Mixing 4 audio channels to 3?

In article ,
DaveC newsgroups wrote:

Remember to get the polarities of C1-C7 correct when you install them
(+ to the op-amp side, - to the outside world).


I presumed that such coupling caps should be non-polar. No?


No need for that. You're going to have an 8-volt bias sitting on each
cap (half of your supply voltage), and the audio signals that they see
will only be a volt or two, peak-to-peak, so the caps will always be
polarized in the direction I indicated.

It's entirely usual and standard practice to use polar electrolytics
in this sort of situation. If you want to get fancy I'm sure you
could find an exotic 'lytic (like one of the new solid-electrolyte
types), but I see no need for that in this application.

You *could* use nonpolar 'litics if you have them around, but as
they're usually more expensive I don't see the point.

--
Dave Platt AE6EO
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