Its possible that one of the drivers are wired out of phase rather an entire speaker. That might sound a bit more spaced out than if both speakers are assembled correctly.
If the speakers and drivers are wired correctly, try bringing the speakers closer together. That should squeeze the soundstage inward and put more centering on the imaging.
Also, to be sure, you are using the same recordings as a basis for comparison, correct? Some recordings use a lot more stereo panning than others. Furthermore, I would expect the Ascend speakers and Salk speakers to share a lot of attributes. They go for the same flat response and both are wide dispersion speakers. They should sound a lot more alike than not. If you want something that has more precise and contained imaging, I would recommend looking at narrower dispersion speakers. Look at the JBL LSR 700 series, specifically the 708 speakers.