If you send one speaker to Danny Richie at GR Research, he will thoroughly evaluate it's performance (frequency response, spectral decay---aka waterfall plot, enclosure resonances, x/o parts quality, etc. If he thinks a redesign of the crossover will improve the loudspeaker's performance, he will design one. All for free!
He sells a product he designed and has manufacture called NoRez. It is applied to the inside of the enclosure walls, to reduce or eliminate resonance if the enclosure requires it. I haven't seen the bracing on the inside of any Tekton, but word is they are rather lightly-braced, the speaker therefore perhaps suffering from audible resonances.
Danny will also sell you all the parts needed to build the x/o he designs for a given loudspeaker, and will lead through assembling it. Or you can have a local technician build it for you. He sometimes finds the x/o design of a speaker satisfactory, but the parts quality poor. He carries a number of audiophile-approved lines of caps, resistors, coils, wire, etc.
