Mona-Steel strings suggest perhaps the inclusion of some monel - a naturally occurring stainless steel sort of alloy comprised of nickel and iron, found, I believe, in the city of Sudbury, Ontario. This old orange box showed up one day and has been propped against the Lafayette PA42 microphone and in front of one of the several remaining RCA 77DXs that still clutter up shelves here at the lab.
But this shot was my first test of a new old lens that I became interested in - a Kodak Aero Ektar, F2.5, able to cover 5X5" film and originally designed for WWII aerial reconnaissance. It is a big lens and had to be specially mounted on a Pacemaker Speed Graphic camera.
The lens can be thought of as sort of an analog of a transducer, or at least the first part of a transducer. This wide aperture lens is regarded by aficionados to have "good bokeh" which is an awkward term used by photogs to describe a nice out of focus effect rather than a blur with spikes, circles or pentagrams in it. When it all goes right, there is a subtle but noticeable "3D" effect in the image where the subject stands out nicely. The field of a microphone is sometimes thought of having an aperture and a focus.