In this paper the problem of estimating the impulse response within a reverberant room is investigated. The target application is that of compensating a stereo or multichannel sound reproduction system for variations in room acoustics and the non-ideal placement of the loudspeakers. The prediction of the impulse response at the locations of multiple listeners requires knowledge of the room geometry and the acoustic impedance of the boundaries. The room geometry and boundary impedances may be obtained by estimating the image locations and amplitudes of a source. This has been addressed by the use of small arrays, with novel geometry, and processing both angular and temporal measurements. Localization results are presented; practical results are compared to theoretical predictions.