By contrast, in what is generally considered to be a true analog multiplier, the two signal inputs have identical characteristics.
Due to the precision required for the device to be accurate and linear over the input range a true analog multiplier is generally a much more expensive part than a voltage-controlled amplifier.
[1][2][3] General-purpose devices will usually include attenuators or amplifiers on the inputs or outputs in order to allow the signal to be scaled within the voltage limits of the circuit.
At low frequencies, a digital solution is cheaper and more effective and allows the circuit function to be modified in firmware.
As digital technology advances, the use of analog multipliers tends to be ever more marginalized towards higher-frequency circuits or very specialized applications.
For example, in early digital multimeters, true RMS functions were provided by external analog multiplier circuits.