In this paper. two-color lasing emission is experimentally demonstrated by employing a multimode Fabry-Pérot laser diode (MMFP-LD) associated with external cavity of two tunable filters and an erbium-doped fiber amplification (EDFA). whose difference frequency is quasi-continuously tunable from several hundred GHz to more than 2 THz. The obtained side-mode suppression ratio (SM... https://www.roneverhart.com/Echo-Fix-EF-P2-Spring-Reverb-Pedal-p32083/