I experiment with various compression driver and horn combinations to build my own system. My preference is the most natural sounding upper midrange and highs. To my surprise RCF ND350 was a disappointment, as I tried it with at least five different horns, and, while sound was clean, even when equalizet to near-flat, there was something not right with this driver to my ear. I got far better results with other drivers, so this one quickly went off the selection. I'm sorry to say this, as the build quality is excellent.