Started with muffled, scratchy sound on the right ear. Was pretty sure it would be a loose connection, but once inside the can, found no loose connections, no electronics, just two solder terminals and a round driver in the center. Hard to understand how something so simple can sound so good.
After resoldering both terminals, I now have NO audio from the driver.
Checking continuity between the 3.5mm stereo plug and the two solder terminals (ie, the ends of the wires in the cable), I found good continuity between one of the terminals and the sleeve, and between the other terminal and the ring.
Also tested for a short between the terminals; none. So between the plug and the can = good continuity.
Next I tested for continuity across the two solder terminals. That would be a measurement of the resistance of the driver coil, right? Found it was open.
Is it a bad driver, or is my test bad?
Grado didn't answer the questions above but offered to repair my headphones for $40 plus postage. Maybe I'm getting tired of them (after only 20 years), but starting to think about getting a new pair from a different company.
Your thoughts would be appreciated.