I picked up a trashed 2220 last weekend and decided to strip it down today. I was surprised to see the differences in the voice coils.
The 2220 is not as rigid, not as deep and mainly paper. The 2225 is very rigid, deeper and with a metal band inside.
From the literature JBL put out when I thought of a 4" JBL edgewound voice coil I always envisioned the one on the right not the one on the left.
The 2220 is on the left 2225 on the right.