[sdiy] Buffers on the LM13x00

[Aaron Lanterman]

I notice in some filter designs, like the Korg MS-20, the LM13x00 buffers 
are used; in others, like several of Ray's, the designer ops to ignore the 
built in buffer and uses op amp buffers instead.

What are the Pros and Cons of each approach?

In particular, I can't figure out how some designs deal with the fact that 
there should be a 1.4 volt drop through the Darlington buffer. The designs 
just look like they ignore the drop altogether.

- Aaron, currently with a case of insomnia

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