In most modern FM transmitters, to produce a better sound, a compressor and a clipper are placed:

The primary goal of a compressor and clipper in an FM transmitter is to control the amplitude of the audio signal. This prevents over-deviation (which causes splatter and adjacent channel interference) while maintaining a high average modulation level for better sound and range. These components must act on the amplified audio signal just before it is fed into the modulator. If placed too early (like right at the microphone), the audio levels are too weak for precise control, and any subsequent amplifier noise or non-linearities might ruin the clipping limit. Placing them in the RF stages (such as between the multiplier and the power amplifier) is incorrect because clipping and compressing are strictly audio processing techniques, not radio frequency processing techniques.