Wolfgang posted a photo on his Instagram yesterday with this text;
"Father and son. The best kind of jam"
It is hard to see Eddie so I cropped and enhanced his photo.
Eddie Bass Dec 29 2014.jpg
Click on the photo to see it bigger. Not sure why it shows up so small.
Playing bass and it looks like he is standing on some kind of "Ass Kicker" pad that helps you feel the bass drum without the need of huge volume.