On Mon, 06 Jul 2009 11:27:54 GMT, (Don Pearce) wrote:

On Mon, 06 Jul 2009 11:32:27 +0100, Jim Lesurf
wrote:

That is so. I use cookbooks for such purposes. FWIW I've put some of the
simpler design rules on the web at

http://www.st-andrews.ac.uk/~www_pa/...rt3/page2.html

The snag is that we still don't know the signal levels, impedances, etc,
that would suit John's requirements.

Well, given the job it is to do, I doubt that levels are important
unless they are so high they cause overload - easily dealt with. And
for impedances, my normal way is to make the input high and the output
low; you seldom go far wrong that way.


There are plenty of circuits available, and yes I could buy in the
components and make them up. But charging my time to do this will make
the result too expensive for the customer.
It would be cheaper to buy these:
http://www.behringerdownload.de/FBQ8...Info_Rev_A.pdf
which are really too good for the job. But in the absence of anything
simpler, that is what I will do.