AbyssHaunt

A free sampler with a built-in reverb engine (70 presets from the developer's Abyss FX) and four macros: Space, Dark, Dirt and Haunt. It ships with 37 presets and 36 samples, loads your own WAV, AIFF, FLAC or OGG files, and has a Hold control that freezes the sound into a drone.

How to use it in horror

Load a single door creak, push the Dark and Haunt macros and press Hold, so it freezes into a sustained drone under a quiet scene.