Size Matters

In the case of my piezo disc pickups, it's bad.

I made a new pickup using a larger disc (about 1 5/16" diameter). I constructed it in the same way as I had the first pickup -- by soldering it to a short piece of guitar cable and then dipping the disc and about an inch of the cable into Plasti-dip.

The large disc gives a strong signal, but distorts very easily, regardless of where I tape it on the soundboard. I don't know whether this is entirely a function of the disc's size or if there is something different about its composition compared to the smaller disc I first used. The sound quality is not great.

I recorded with the large pickup taped behind the bridge of my nylon string guitar. I plugged it directly into the Firebox. I then recorded the same bit with the smaller disc pickup, also taped behind the bridge and plugged directly into the Firebox. The difference in frequency response is significant, with the larger pickup sounding like it's playing through a portable AM radio. This isn't necessarily always bad though as I can used this pickup when I want a lot of midrange.

Large piezo disc pickup

Small piezo disc pickup