Electro-Harmonix Q-Tron Plus

The ultimate envelope follower Same as the original Q-Tron but with added Effects Loop and Attack Response Switch. The Effects Loop lets you place an additional effect between the Q-Tron+'s preamp and filter section without changing the envelope drive. The added Response Switch lets the player choose between a slow, smooth, vowel-like attack and the fast, snaked response of the original Q-Tron.