> Thanks everyone for the replies. That's sort of what I 
> expected...I
> guess my confusion came in that I saw a schematic 
> supposedly for audio
> that had Vee tied to ground.

The key point from the answers wrt to your original question 
which was essentially -

> ... D4052 4 channel multiplexer ...I'm considering using
> it to switch some audio signals (consumer line level) and 
> I'm really
> not quite sure what voltage Vee wants to see.
... I'm trying to figure out is if I can run this all off a
> single ended 12V supply or if I need both positive and 
> negative
> supplies.

is, YES.

You can do what you wanted provided that the AC signals are 
somewhat less than 12 VAC peak to peak and are biased so 
that their mid point is at about 6 VDC (ie half way between 
Vdd and Vee).

The DC level of an AC signal is easily altered and setting 
it to 6V here is liable to be an easy and reasonable thing 
to do. The 4052 will basically do what you want although, as 
people have noted, there are better devices available if you 
want to pay for them.

All analog muxes are liable to have the restriction of 
needing the AC signal to lie within the analog power supply 
rails, and not all will allow a separate DC supply range 
which is less than the AC range, so the 4052 is superior to 
some alternative higher-quality solutions from a power 
supply and control point of view.


        Russell McMahon



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