A repeater comprising: a rare-Earth doped fiber amplifier that amplifies an optical signal and operates at least partially in the gain saturation regime; a doped fiber amplifier optical pump configured to supply optical pump power to the rare-Earth doped fiber amplifier; a Raman pump configured to provide Raman amplification to the optical signal in which the Raman gain of the optical signal has a tilt of at least 1 dB, wherein the tilt is the maximum Raman gain experienced by any optical channels of the optical signal minus the minimum Raman gain experienced by any of the optical channels of the optical signal; a tilt sensor configured to detect tilt of the optical signal downstream of the rare-Earth doped fiber amplifier in the optical path; wherein the tilt of the optical signal detected by the tilt sensor is the maximum signal gain of any of the optical channels minus the minimum gain of any of the optical channels; and a tilt adjustment mechanism configured to permit adjusting of the tilt to within 1 dB gain by controlling a power of at least one of the optical pump power (231,232) supplied by the doped fiber amplifier optical pump and the Raman pump that influences tilt measured by the tilt sensor; wherein an output optical signal power from the rare-Earth doped fiber amplifier is at least ten percent of a corrected optical pump power received at the rare-Earth doped fiber amplifier from the doped fiber amplifier optical pump, wherein the corrected optical pump power is the amount of optical pump power provided to the doped fiber amplifier corrected for differences in wavelength, the correction calculated as the pump wavelength over the signal wavelength. a rare-Earth doped fiber amplifier that amplifies an optical signal and operates at least partially in the gain saturation regime; a doped fiber amplifier optical pump configured to supply optical pump power to the rare-Earth doped fiber amplifier; a Raman pump configured to provide Raman amplification to the optical signal in which the Raman gain of the optical signal has a tilt of at least 1 dB, wherein the tilt is the maximum Raman gain experienced by any optical channels of the optical signal minus the minimum Raman gain experienced by any of the optical channels of the optical signal; a tilt sensor configured to detect tilt of the optical signal downstream of the rare-Earth doped fiber amplifier in the optical path; wherein the tilt of the optical signal detected by the tilt sensor is the maximum signal gain of any of the optical channels minus the minimum gain of any of the optical channels; and a tilt adjustment mechanism configured to permit adjusting of the tilt to within 1 dB gain by controlling a power of at least one of the optical pump power (231,232) supplied by the doped fiber amplifier optical pump and the Raman pump that influences tilt measured by the tilt sensor; wherein an output optical signal power from the rare-Earth doped fiber amplifier is at least ten percent of a corrected optical pump power received at the rare-Earth doped fiber amplifier from the doped fiber amplifier optical pump, wherein the corrected optical pump power is the amount of optical pump power provided to the doped fiber amplifier corrected for differences in wavelength, the correction calculated as the pump wavelength over the signal wavelength.