I reconstructed the following query, as the answer to your question was already in the text you pasted.

Kevin

So if this setting txprelim=yes   is:
 
TX audio processing. Options: (no,yes).

Choosing yes turns on transmitter preemphasis and peak limiting, along with a lowpass filter. The yes option is used when driving an FM transmitter directly by injecting audio right into
the modulator.

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What is the setting?
txlimonly=no

The no option provides audio which should be injected into the microphone input of the transmitter or at some point in the transmitter' speech amplifier before preemphasis, and limiting.