As rolling noise of trains is generated by wheels and rails, the noise radiation of these two sources can be reduced by damping systems mounted directly at the sources themselves. Today the development of new rail absorbers need costly tests directly at wheels or rails under working condition on railway lines to verify the efficiency of the absorbers. The DeuFraKo supported R&D-project STARDAMP is aiming at new techniques to prove the efficiency of new absorbers at laboratories before the final stage of the homologation procedure is needed, to save both money and time along the development process. This paper is dealing with the process of testing rail absorbers at rails with a finite length, which can be used for indoor tests. Beside the comparison of measured damping effects of rail absorbers at endless rail versus finite rail, the methodology of collecting data (= Track Decay Rate measurements) will be highlighted. The paper is addressed to developers of rail absorbers as well as to consulting engineers to discuss new measuring techniques in railway noise