This. To get it, you need to complete One Piercing Note. Here are the steps to getting it.
- Complete One Piercing Note.
- Get a Ring of Visibility and a Ghostspeak amulet.
- You're now going to need 6 pieces of Saradomin armour. Personally, I would get the Citharede robes, this gives you half of the necessary six, and they're free from the wardrobe in the basement of the abby. The cheapest way to have all 6 items is the Citharede robes, a Saradomin Arrow, Saradomin Crozier and a Damaged holy book.
- Go to the basement of the abby with full energy, health (and I believe you need full prayer points too.) And touch the holy reliquary.
Just a warning in case you're a pure, you will get 50K prayer experience for receiving the harp.