It's possible to pan instruments in each of the Drum Kits in the TD-15.
Here's how:
1. Choose a desired kit to edit.
2. Press MENU.
3. Press F1 (INST).
4. Press F2 (EDIT).
5. Press the cursor down button repeatedly to choose "Pan."
6. Hit the pad that you want to adjust the panning for.
7. Turn the dial to adjust pan setting (L15 - CENTER - R15).
8. Repeat Steps 6 and 7 for the other pads as desired.
9. Press EXIT when you're finished. The new settings are saved in the kit automatically.