Electroacoustic absorbers consist in employing loudspeaker diaphragms as resonator absorbers with adjustable performance. They have been recently shown to allow almost perfect sound absorption (&ₐlpha;>0.8) in the low-frequency range, typically in the range of a few octaves around the natural resonance frequency of the membrane. Several passive (open circuit, shunt electric networks, stacked cabinets, etc.) and active concepts have been developed since then, showing outstanding broadband performance in the low-frequency range, up to more than 1 frequency decade (from 20 Hz to 500 Hz in the best cases reported so far). Therefore, they have been assessed as an efficient solution to address room modes damping in the low-frequency range, outperforming the existing passive solutions available so far. In this presentation, an active electroacoustic absorber prototype will be tested as a perfect anechoic termination down to 20 Hz, in order to facilitate the measurement in a standard impedance tube facility. In that view, several control strategies will be deployed at the end of a tube, and the results in terms of Transmission Loss measurements will be compared.