Gyroscope is a Filter modulated by an independent Triangle Wave or Stepped Wave.  

What the knobs on this do? the Vol controls the input gain that is filtered, unity gain is achieved aprox. at 50% of the dial. The Resonance set the open-ness of the vowel (in this case the wah-wah vowels). Depht  selects how much the wave is going to modulate the filter. Rate controls the speed of the Triangle Wave, in this mode the sound is kinda like a phaser, and at high speed it also have a nice vibe sound going on it. Speed  controls the Stepped Wave, in this mode the sound is like a pseudo/quasi sample and hold, there's an exp jack to control this parameter via an expression pedal. The toggle select wich wave is going to modulate the filter. Gyroscope is only powered via a 9v DC adapter (center negative as most pedals - boss, digitech, etc) there are no options for battery usage.

Features.

• Dimensions 4 5/8" x 2 1/2" x 1 1/2".
• Volume, Rate, Depth, Speed, Resonance and Rate controls.
• Expression Pedal Jack to control Speed of the Step Wave.
• Powered only by DC 9v power Jack (center negative).
• Jacks on top to save pedalboard space
• TrueBypass Switching and Led Indicator.
• Lifetime warranty