Dynamic features of a non-polarized Erbium-doped fiber ring laser subjected to external cavity-loss modulation

•Experimental external cavity-loss modulation on EDFRL using loudspeaker modulator.•Linear and non-linear dynamical behaviors are seen in EDFRL under loss modulation.•EDFRL is sensitive to acoustic wave at driving amplitude < 200 mV to < 1000 mV.•EDFRL acts like a damped non-linear oscillator at 500–1000 mV driving amplitudes.•Two regions of optical bi-stability are obtained during loss modulation.