Heads need time to stabilize or "seat" into the rims and conform to the bearing edges. You can seat the heads by playing but a quicker way is to press the heads with your hands (like giving CPR) while tuning the drums.
Heads need time to stabilize or "seat" into the rims and conform to the bearing edges. You can seat the heads by playing but a quicker way is to press the heads with your hands (like giving CPR) while tuning the drums.