I own a pair of Shure SE846 earphones. I want a custom cable that is a specific length. Does Shure offer custom cables?
Sorry, Shure does not offer custom made cables.
There are companies, not associated with Shure, that do offer after-market custom made cables. Here is an example: http://www.plussoundaudio.com/customcables/inearmonitor.html
Shure does not endorse custom cables made by other companies; Shure does not test custom cables made by other companies; Shure does not endorse any specific company that sells custom cables. The information above is provided only as a service to Shure customers seeking such cables. Note that using non-Shure cables on Shure earphones could result in the Shure product warranty being null and void.
For reviews of after-market cables: http://www.head-fi.org/