Analysing system response in the time domain from Bode plot (intuition)
A rough calculation for the first harmonic at 2kHz - assuming a gain decrease of 40dB/dec above 700 Hz - results in a damping factor of app. 9.44 (19.5dB). Hence, the first harmonioc at 2kHz should have an amplitude of 10/9.44=1.06 volts. 

Visual justification: At f=1kHz we have a damping of 7.5dB (factor 2.37) 

EDIT1: Due to some incorrect numbers (obtained from the diagram) I have corrected the damping values slightly. 

EDIT2: Simulation of a corresponding 2nd-order lowpass with a squarewave input results in sinusoidal signal (good quality) with an amplitude of app. 1.3 V. This is more than roughly calculated above - however, the filter data couldn`t be quite exact because the evaluation of the given magnitude response is not error-free (pole frequency?, 0 dB crossing of the asymptote or the actual curve ?).