That statement goes both ways. I have watched audio guys create a
design that was the equivalent of putting a gun to their head when it
started to get out of the kHz ranges. Frequency is the great equalizer
that forces the first two words out of my mouth while forming an answer
to be "It depends.... As an EMC engineer I get to go from audio to
microwave problems and everywhere in between. Like the BASF guy, I
don't make the product, I make it better.
The rules change with each order of magnitude increase in frequency.
Wondering when resistance stops and inductance takes over as the
limiting factor in a path or when resistors and capacitors and inductors
stop acting like the components we were taught about or when stray
capacitances that don't even show up in the schematic start to dominate
a design are all examples of things that get treated differently with
I don't know many (any) design guidelines that go from DC to Daylight.
You can fill volumes on ferrites and their use, one of my favorite
misunderstood things as evidenced by so many of the questions that come
My two bits worth....time to go back in my box.
Oh yeah, my percentage of BW is really high.
*I'm not denegrating the discipline of RF engineering, but rather
*audio can be FAR more complex than RF, and that I've seen some very
*engineers screw up badly below 100 kHz. Witness the K3 (which I own and
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