Operation confirmed. Only the DD-6 has the WARP function, which continuously increases the level, unlike other models. (Other models have a fixed level.) A digital delay that achieves a variety of echo effects. - Model Name: DD-6 - Type: Digital Delay - Output Terminals: OUTPUT A, OUTPUT B - Input Terminals: INPUT A, INPUT B - Power: AC adapter or 9V battery - Settings Table: A table with various settings is included. Thank you for viewing.