Martin J King Mathcad Worksheets

In a standard TL, the driver is at the closed end. King provided specific worksheets to model placing the driver 1/3 or 1/2 down the line, which helps smooth out standing wave ripples.

Most standard modeling software (like WinISD) uses "Lumped Parameter" modeling—treating the box as a spring with a single pressure. MJK’s worksheets use Distributed Parameter modeling. martin j king mathcad worksheets

Martin J. King is a retired mechanical engineer with a background in vibration analysis. In the early 2000s, he turned his analytical eye toward a long-standing problem in audio: the transmission line (TL) loudspeaker. Unlike ported boxes (bass reflex) or sealed enclosures, transmission lines were considered "black art"—tricky to model, difficult to build, and heavily reliant on trial and error. In a standard TL, the driver is at the closed end

King’s contribution was to apply transmission line theory (often used in RF engineering and telecommunications) to low-frequency acoustics. He wrote extensively in the Audio Engineering Society (AES) and, crucially, released his work via Mathcad—a engineering calculation software that allows for mathematical notation, live solving, and data visualization. Martin J