TC Electronic CRESCENDO AUTO SWELL Responsive Crescendo Pedal with 2-Knob Interface for Haunting Guitar Line Manipulation : Amazon.co.uk: Musical Instruments & DJ
Volume Swells
Gloamer - Pigtronix
New Outlaw Effects Late Riser Auto Volume Swell Guitar Effects Pedal | eBay
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Pigtronix Gloamer: Auto Swell with Spicy Surprises!