Shure E4 in-ear earphones Custom Earmolds From Westone
At least two companies, Westone and Sensaphonics, make custom earmolds that fit Shure headphones. Shure works closely with Sensaphonics, whom they recommend on their website and in their product literature, but I went with Westone because that's the company my audiologist usually works with.
The audiologist stuck a piece of cloth in my ear to protect the eardrum, then injected foam in the ear canals. During the two minutes the foam takes to harden, Westone recommends you keep your mouth open for best results. When my audiologist asked why, a telephone rep told her it was because the headphones were intended for musicians, who want to keep a good seal while they're singing. My audiologist thought this strange: Presumably, I wouldn't be listening to music with my mouth open, so why should my earmolds be formed in that position? I compromised, talking and moving my jaw around a lot as the foam hardened (footnote 1).
Once the foam solidified, the audiologist removed the impressions from my ear canals and I selected a color; the options included forest green, neon pink, marble red, and various swirly combinations. Being boring, I went with clear. She mailed the impressions to Westone. A couple weeks later she called, and I went to pick up my new Westone UM56 earmolds.
My experience has been mixed. The first mold made for my right ear didn't fit well. I used it for two weeks and struggled the whole time to get a good seal. Westone provides a 30-day guarantee, so I went back to the audiologist, who took a new impression, and Westone made a new earmold. It works much better.
Still, they're a little fiddly. There is one position at which they fit best, but even then, they don't fit my ears like keys in locks; if I rotate them a bit too far, they don't seal out outside noise nearly as well, and the bass response suffers. Properly inserted, they're very comfortable, and the isolation and bass response are excellent. But during the course of a gym workout they can move around; it's easy to lose a good seal. Overall, I'd say Shure's compressible foam sleeves—which are also quite comfortable—work better, at least for me.
Footnote 1: When I had my ear molds made for my review of the Ultimate Ears UE5C headphones (December 2004), the audiologist told me that I must keep my mouth open and my jaw still for the impression to take the optimal shape. I wonder if the fact that Jim talked while the impressions were taken of his inner ears led to the less-than-perfect seal.—John Atkinson