variable-gain amplifier , VCA (Abkürzung)

A simple gate variable-gain amplifier is used with a 47 F capacitor, and the filter is behind it.

The monophonic bass sound available on the lower half of the keyboard has no variable-gain amplifier but has a low-pass filter.

The square wave passes the variable-gain amplifier built as a CV/Gate and a pulse conversion.

Both the loudspeaker switching and the gain of the variable-gain amplifier were under the control of a control track recorded on the Vitasound print.

A digitally-controlled amplifier (DCA) is a variable-gain amplifier that is digitally controlled.

Analog signals may pass through one or more analog notch filters and a variable-gain amplifier (VCA)

It has full polyphony with a variable-gain amplifier for each key and a BBD (Bucket Brigade Delay) chorus that gives it the distinctive string synthesizer sound.

The signal entering a compressor is split, one copy sent to a variable-gain amplifier and the other to a side-chain where a circuit controlled by the signal level applies the required gain to an amplifier stage.

The additional apparatus required for Vitasound was relatively modest: two additional loudspeakers, the variable-gain amplifier and relay unit, and a reader for the control track which was a fairly easy retrofit to existing 35mm projectors.

While the dynamic range compression used in audio recording and the like depends on a variable-gain amplifier, and so is a locally linear process (linear for short regions, but not globally), companding is non-linear and takes place in the same way at all points in time.

In order to achieve a wider sound source and greater dynamic range the Vitasound system employed additional left and right loudspeakers which could be switched in parallel with the normal center loudspeaker, and a variable-gain amplifier which could increase the replay volume by up to 10dB.