I had purchased the newer black coned Hi-Vi M5N-B a little while back, finally swapped one into on of my AlTi speakers and tested it against the original M5N. The frequency response overlaid nearly perfect, so those are a drop in swap for this design if you like the look of the black woofer cone over the original M5N's light copper/gold color. Added some new photos of that woofer on the few posts.