MMCX Connector Mod for Grado Headphones

thingiverse

Despite rather liking them, I feel that Grados have a significant design flaw as there is nothing to prevent the ear cups from fully-rotating in one direction over and over again, twisting the non-detachable cables and causing them to eventually fail. Detachable cables help solve this problem, so here is my solution. I generally don’t like modify things in a way that prevents them being returned to their original spec, so I wanted a smaller connector than a 3.5mm jack, which would require the original opening to be enlarged. I settled on the MMCX connector, which has a tiny M3 mounting thread. This printed part gets sandwiched between the two ear cup halves, with the MMCX connector threaded into it The way the two ear cup halves were glued together, which prevents convenient servicing, is something I also wasn't a fan of, so I used some M3 screws to secure the two halves together. This breaks my previously mentioned preference for avoiding irreversible modification, but sometimes it's unavoidable. I used the 8.5mm spacer jig to get the spacing between the two halves consistent all the way around and to ensure the MMCX holder was being tightly retained. Holes were drilled through both halves in four positions. Then the inner holes were tapped, while the outer holes were drilled out and countersunk. The cable is a cheap replacement for the Audio-Technica ATH-ES9, which uses their A2DC connectors. These had to be cut them off and re-terminated. I struggled to find an MMCX cable with a thicker cable diameter than the ones sold for in-ear use. I’m sure they’re out there somewhere, I just couldn't find one (I have since found suitable pre-made cables on aliexpress).