Help with Dunlavy SC-IV signature

Hello to all. I friend recently gave me a pair of SC-IV as they were too big for his room and he did not like their sound. The speakers sounded very bright to me but I attributed that to the cheap surround sound receiver he was using. I expected them to sound way better on my gear. No such luck. I tried them with a Moon P5 and Ayre v3 and they made my ears bleed, same with aMusical Fidelity M6PRX and Pre. I finally put then on a Nakamichi CA7 and PA7 with the tone controls all the way back and they started to sound way better. My current speakers are Martin Logan Expression 13A and Von Schweikert VR4 Get III. I added a Behringer DEQ2496 and turned the mids and highs down 7db and now they sounded very good. I have had Vanderstein 5A, Magnepan 3.7i and Utopias among others and I have never encountered something this bad. It's as if an equalizer was turned all the way up in the mids and highs. I removed one of the crossovers and to the eye they look ok I would have to remove them and measure everything to know for sure. Has anyone run into this before ? should I rebuild the crossover to see if it will improve ? What other measurements should I take ? Thanks in advance for your assistance.