Mated these tweeters up with 2 pair of the EM 8ohm Cerwin Vega 6 1/2 inch mid/woofers wired in parallel to give a 4ohm load..absolutely awesome sound..typical of Cerwin Vega..clean crisp..clear & loud !! all in an open baffle configuration - style cabinet I made. I am so impressed with the clarity their amazing !! with the EM CR 28 4ohm xover...you cant go wrong !! (see my other reviews) ps: watch the cut out hole size..you only get about 5 mil left to screw into..oops ! Praises for EM"s staff for advice..price & prompt shipping..any other Ozies lookin' for quality @ realistic prices..go for it..thanks EM- guys you were great !!