We present novel methodologies for compounding large numbers of 3D echocardiography volumes. Our aim is to investigate the effect of using an increased number of images, and to compare the performance of different compounding methods on image quality. Three sets of 3D echocardiography images were acquired from three volunteers. Each set of data (containing 10+ images) were registered using external tracking followed by state-of-the-art image registration. Four compounding methods were investigated, mean, maximum, and two methods derived from phase-based compounding. The compounded images were compared by calculating signal-to-noise ratios and contrast at manually identified anatomical positions within the images, and by visual inspection by experienced echocardiographers. Our results indicate that signal-to-noise ratio and contrast can be improved using increased number of images, and that a coherent compounded image can be produced using large (10+) numbers of 3D volumes.