Quadrex rhymes with:
forex, purex, rorex, abex, albunex, alpex, ashtec's, avanex, cognex, complex, cortex, culex, dudeck's, forex, gemex, genex, ibex, immunex, index, inlex, koscheck's, micrografx, mondex, moulinex, ovex, pantex, patlex, proctorsilex, purex, qualex, quanex, reflex, rolex, rorex, royex, semtex, simex, spinifex, timex, trizec's, uzbeks, vortex
Quadrex sounds like:
quattrocchi, quattrochi, quitters