I virtually never used the pickup in my J10E. Recently a chance to play came up so I tried plugging it in. I never expect a lot from a Piezo but it sounded rather bad even for a Piezo. A bit crackly/distorted yet the low E seemed to ring clear. How sensitive are they to low battery power? Is distortion a symptom?  I tried to replace the battery and the snap broke. I have a replacement ordered and will solder that in shortly and will advise on any change once that is complete.

Since the pickup has no onboard preamp, I expect something will need to be acquired to feed a PA? I thought maybe a decent comp also but I would not expect to need much else. Thoughts on that?

Its a 1998 J10E

Low battery will definitely result in uneven sound and distortion.  Bummer about the snap breaking.

Should just need your 1/4" cable out to a DI box to xlr to the PA  - I played most Sundays with that setup for years. 

Currently though I do use either a Tech 21 Acoustic Flyrig or a Line 6 Pod Go for some light compression, EQ, and reverb that all help the piezo pickup not sound so thin/metallic through the sound system.  A decent sound guy can handle those things on the board, but I like using one of the pedal units for better consistency from venue to venue.