Perhaps his most famous contribution, these worksheets modeled the complex roll-off and floor reflections of speakers without enclosures, helping designers manage the "dipole peak."
The critical acoustic interactions caused by placing the driver or the exit port at specific intervals along the line. Overview of the Core Mathcad Worksheets
). The worksheets immediately check these values against internal physics constants. Defining Cabinet Geometry
Assuming you have obtained a legitimate worksheet file (e.g., Classic_TL_4_0.xmcd ), here is how to extract value from it. martin j king mathcad worksheets
MJK worksheets often assume an infinite baffle (or a very large baffle) for the front surface. Real-world, narrow cabinets will have a "baffle step" (loss of low frequencies), which may need to be corrected in the final design.
Martin J. King's Mathcad worksheets have gained significant recognition due to their clarity, accuracy, and comprehensive coverage of various mathematical topics. King's worksheets are designed to provide step-by-step solutions to complex problems, making them an invaluable resource for students and professionals seeking to understand and apply mathematical concepts. His worksheets have been widely used in academic and industrial settings, and have helped to:
They cover a variety of enclosures, including simple transmission lines, mass-loaded transmission lines (MLTL), tapered quarter-wave tubes (TQWT), and back-loaded horns. Key Concepts in the Worksheets Quarter Wavelength Loudspeaker Design Defining Cabinet Geometry Assuming you have obtained a
Unlike simplified TL calculators, King’s worksheets solve the wave equation for specific cabinet geometries, providing high accuracy compared to physical measurements.
However, the legacy persists. While you cannot always get the raw .xmcd or .mcd files directly from his main landing page, the community has preserved them via the and dedicated DIY audio forums (DIYAudio.com, AudioKarma, The Loudspeaker Building & Design Facebook groups).
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. Martin J
Produces graphs for SPL (Sound Pressure Level) at the woofer, SPL at the port, total SPL, driver displacement, and electrical impedance. Why Choose Mathcad for Speaker Design?
Martin J. King (often referred to as MJK) is a legendary figure in the DIY audio community. His Mathcad worksheets are considered the "gold standard" for modeling quarter-wave loudspeaker enclosures (Transmission Lines, TQWTs, and Horns).