FL Studio

FL Studio opens samples in HARP as an external audio editor.

Link HARP

1. Choose Options > File settings (F10).
2. Under External Tools, click the file icon beside File, and select HARP.
3. Select HARP in the list of tools, and enable Launch with file and Default Editor. HARP then replaces Edison wherever FL Studio offers to open audio in an editor.

The manual of Image-Line describes the setting under File Settings.

Open Audio in HARP

HARP overwrites the file of the sample, wherever it is, including a sample from a pack. Copy the file first if you want to keep the original.

1. In the Channel settings of a sampler channel, choose Edit... (E) from the Sample menu, which opens the sample in HARP.
2. Process the DAW-linked track and send the result back, as in The Round Trip.
3. Choose Reload from the same Sample menu, which loads the changed file.