The possibility to alter a room’s acoustic conditions is useful for spaces requiring specific acoustics depending on diverse functions they serve. Such solutions are applied mostly in multipurpose auditoriums and concert halls, as well as in audio research facilities. The variable acoustics laboratory Arni, a facility within the Acoustics Lab of Aalto University in Espoo, is an example of a space where the wall absorption can be altered considerably with the help of specialized wall- and ceiling-mounted panels. The present work shows the results of measurements of over 5000 panel combinations in Arni, showcasing the change in values of the room acoustic parameters, such as reverberation time and clarity, in relation to the variation of the wall absorption.