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Advanced Transition Horns
by Marcel Batík

"Advanced Transition Horns" (ATH) are acoustic horns and waveguides created utilizing formulas described in the following papers.
These novel formulas combine a controlled-directivity approach of Dr. Earl Geddes (OS waveguide) with an all-smooth horn-to-free-air transition,
providing a modern, high-performance blend for quality sound reproduction.

Papers on horns:

OS-SE Waveguide (pdf) / baffle mounted
R-OSSE Acoustic Waveguide (pdf) / free standing
Spherical Wave Forming (pdf)


ATHEX Waveguides

Interactive formulas in Desmos calculator: OSSE | R-OSSE

Associated diyAudio threads: Theory & Design | Practicalities

Sample waveguide ST260

ATH software is no longer maintained.
The last released package: Ath 4.8.2 with a User Guide; the latest beta-build.

The latest web update: August 27, 2023


If interested, please contact the author via e-mail or the diyAudio thread.