This is what you need to do to turn on or off both key-tap sound and key-tap vibration:
1. Setttings>My device>Input and language
2. Next to "Samsung keyboard", tap the gear icon
3. Scroll down to and tap "advanced"
4. Check/uncheck "key-tap sound" and/or "Key-tap vibration
With the new lollipop upgrade, the key tap vibration option is greyed out, and I cannot select it. Anyone have any ideas why? Prefer the haptic feedback to the sounds....