A fiber laser amplifier system comprising: at least one master oscillator providing an optical seed beam at a certain center wavelength; at least one phase modulation electro-optic modulator, EOM, responsive to the seed beam and a first RF drive signal, said phase modulation EOM phase modulating the seed beam using the first RF drive signal so as to broaden its spectral linewidth to span a carrier spectral band; at least one frequency modulation, FM, EOM responsive to the phase modulated seed beam and a second RF drive signal, said FM EOM frequency modulating the seed beam using the second drive signal so as to broaden its spectral linewidth beyond the carrier spectral band; at least one amplitude modulation, AM, EOM responsive to the phase modulated seed beam and a third RF drive signal, said AM EOM amplitude modulating the seed beam using the third drive signal so as to provide an amplitude modulated seed beam that is synchronized with the frequency modulated seed beam; at least one non-linear fiber amplifier receiving the AM and FM modulated seed beam and a pump power beam, said amplifier amplifying the seed beam using the pump beam to provide an output beam where most of the beam power resides in the carrier spectral band; a beam sampler sampling off a sample beam from the output beam; a filter receiving the sample beam and filtering out the carrier spectral band from the sample beam; a photodetector for detecting beam power of the filtered sample beam and providing a beam power signal; and a controller receiving the beam power signal, said controller controlling one or more of the second drive signal, the third drive signal and the pump power beam to change the FM modulation depth, AM modulation depth and/or pump power in a manner that reduces the beam power of the filtered sample beam. at least one master oscillator providing an optical seed beam at a certain center wavelength; at least one phase modulation electro-optic modulator, EOM, responsive to the seed beam and a first RF drive signal, said phase modulation EOM phase modulating the seed beam using the first RF drive signal so as to broaden its spectral linewidth to span a carrier spectral band; at least one frequency modulation, FM, EOM responsive to the phase modulated seed beam and a second RF drive signal, said FM EOM frequency modulating the seed beam using the second drive signal so as to broaden its spectral linewidth beyond the carrier spectral band; at least one amplitude modulation, AM, EOM responsive to the phase modulated seed beam and a third RF drive signal, said AM EOM amplitude modulating the seed beam using the third drive signal so as to provide an amplitude modulated seed beam that is synchronized with the frequency modulated seed beam; at least one non-linear fiber amplifier receiving the AM and FM modulated seed beam and a pump power beam, said amplifier amplifying the seed beam using the pump beam to provide an output beam where most of the beam power resides in the carrier spectral band; a beam sampler sampling off a sample beam from the output beam; a filter receiving the sample beam and filtering out the carrier spectral band from the sample beam; a photodetector for detecting beam power of the filtered sample beam and providing a beam power signal; and a controller receiving the beam power signal, said controller controlling one or more of the second drive signal, the third drive signal and the pump power beam to change the FM modulation depth, AM modulation depth and/or pump power in a manner that reduces the beam power of the filtered sample beam.