How a Diode + LFO Becomes a Tremolo-style Guitar Effect (No Op Amps) скачать в хорошем качестве

How a Diode + LFO Becomes a Tremolo-style Guitar Effect (No Op Amps)

In the first two videos of this series, I showed how a simple diode can be used as an audio switch by applying large forward and reverse bias voltages. In this video, I take that idea further and explore what happens when the diode’s bias voltage is brought into its nonlinear transition region instead of staying far above or below it. By gradually reducing the bias voltage toward the diode’s forward voltage, the diode no longer behaves like a hard on/off switch. Instead, its resistance changes smoothly and exponentially, causing the audio signal to attenuate rather than abruptly cut off. This reveals a powerful and often overlooked property of diodes: when properly biased, they behave like voltage-controlled resistors. Using a simple potentiometer and an inverting amplifier, I sweep the diode’s bias voltage between +9V and −9V while observing the resulting waveform on the scope. As the bias moves closer to the diode’s conduction threshold, the waveform distorts asymmetrically, demonstrating how nonlinear conduction affects audio signals. In the second half of the video, I drive the diode’s bias with a low-frequency oscillator while passing a guitar signal through the circuit. The result is a voltage-controlled amplitude modulator, or tremolo effect, created with nothing more than a single diode and a control signal. By changing the LFO waveform (sine, triangle, square, saw, and even an EKG signal), the musical character of the tremolo changes dramatically. This experiment shows how one inexpensive component can act as an audio switch, a voltage-controlled attenuator, and a tremolo effect, all by exploiting the diode’s nonlinear behavior. Vintage circuits. Modern tone. Endless curiosity. Subscribe for more deep-dive experiments in guitar electronics and analog audio. 👉    / @madscientistguitarlab   Affiliate Links: Octopi Tshirt: https://amzn.to/48COJzk