It's why there is AMC and ALC in SSB radios...
You are aware that typical Galaxy-Class radios, along with nearly any 11 Meter SSB rig, uses two DIFFERENT amplifiers even though it uses a main one you can call as a third, but that 3rd one is used as a Mic Pre amp.
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You ask a great question, with a complex answer.
The solutions to amplify the signals are done in different ways, beasts - harbingers.
One requires your audio signal to combine, right away, with a low-level Intermediate frequency to allow it to be amplified as RF. (Balanced Modulation)
Another uses your Audio Signal to control a BIAS (amplification) of Carrier and impose audio using BIAS as a means to make AM and FM.- with FM using a section of the PLL tuning to SHIFT frequency by making the tunnig section change with audio.
AM and FM use the same Regulation circuit, AM adjust Regulation circuit with Audio to Affect BIAS power.
FM uses FIXED Regulation Bias but PLL controls the SHIFT of Audio for FM.
So in the above, it is why one amp may Rule all, but cannot be the only solution - so the TONAL effects, The signal Amplification as well as MIXING efforts - all make changes to the Audio presence.
So in a way, the AMC can help with carrier and envelope, another ALC helps with LIMITING the audio peaks during this process - used more for SSB modes - but can be made to have the last word on all.
So, in some form of another...
You have RF Compression occurring - during SSB modes - ALC
You have AM Modulation Compression occurring - in AM mode - AMC.
You have FM Deviation Compression occurring - in FM mode - AMC/AVC
Each mode depends on the other. But one type of limiting or Audio Signal Gain as well as Dynamic - cannot be controlled by just one - it needs the others - and in some ways, AVC (Automatic Volume Control) is controlled by the USER (Gain) thru the Mic Amp/Preamp section.
