Voltage Controlled Amplifier Diy

Subsequently it is the main signal and all the alterations are made to this signal.

Voltage controlled amplifier diy. A vca or voltage controlled amplifier lets you use a voltage to control the amount of another signal that is allowed through to the output of the module. Since the traditional use of a vca is to turn down a signal until control voltage is applied max cv into a vca will set the amplifier to unity gain or 0dbv no gain. One option to build your own is a jfet junction field effect transistor based voltage controlled amplifier. The higher the control voltage the more signal is passed.

0v cv into the vca will cause it to fully attenuate i e 80dbv. Voltage controlled amplifier vca by scott rise. Since this oscillator is voltage controlled we need to change the voltage in order to watch the frequencies change. With a p channel jfet you apply a positive voltage to turn it off.

Effectively most vcas are actually voltage controlled attenuators. Incrementally lower voltages turn the jfet on more lowering it s resistance. A jfet can function like a variable resistor. Changing the voltage on the power supply is not a good idea because the op amp needs a specific and constant power supply to function we are only in possession of one variable dc voltage supplier.

Carrier signal input this is the input where a bipolar signal comes in. In a modular synth their primary job is make notes start and end the volume is to raise when a key is pressed and it s told to lower again when a key is released.