Fishman AFX REVERB Manual page 9

Controls
Level
The level control mixes the selected effect in parallel, adding as much or as little
reverb as you want in addition to your direct sound. This means that your tone is
preserved while the effect is blended into it.
Tone
Use this to add brightness or warmth to the sound of the effect without altering
your direct sound.
Decay Time
Adjusts the overall length of the reverb "tail."
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