Tube XO Schematics* 18_04_05

Heath XO-1 Marantz Audio Research Larson & Cretien (bessel 2nd order) -- 7 kHz Larson & Cretien (bessel 4th order) -- 5 kHz Both the above are also here 1st order Butterworth 3rd order Butterworth TubeCAD aricle on tube XOs

* the 1st 5 have been redrawn from maps found here [Back to Transmission Line Speakers | Tech Articles]