EM 172 again!

["Max" oatcruncher]

Sorry again for my ignorance here, but I'm confused about there just being =
two wires coming out of my EM 172's. I found a post from 2010 that showed c=
apsules with no wires at all, just three solder blobs on the base, and indi=
cating which was hot, neg and ground. It's clear to me what the two wires a=
re, but is a ground required please?
As I've got my soldering gear out, I thought I might do some experimenting =
with these capsules, but obviously I don't want to damage them.
Also, will the PIP supplied by my LS-10 be sufficient to power them?
Cheers
Max