Yes, a new amp can make a change in the speaker location beneficial. HOWEVER, before you start playing "Waltzing Matilda" with those big boxes (I realize its relatively cheap and easy to do, but it can be frustrating as well) think about the possibility that your notice of some localization of sound may be due to the amp, or more probably the tubes you are using, than the amp/speaker interface/location.
FWIW, I went thru this with my Tylers - I was getting some piano notes, along with other instruments such as the clarinet, sticking out like sore thumbs in the upper mid range. A very narrow range. Initially I thought it was the Tylers, then I blamed the amps, ultimately what I discovered was that the utilization of KT88's in that particular amp (not in my other amps though) that was causing the problem. Put in 6550's and the problem went away. This also applies to small tubes as well. Now if you have changed your input tubes and no matter what kind you use it still is a problem then it might be your speaker location. Might be. But I'd be more willing to bet it was a speaker/amp interface problem than anything else. JMHO. Hope you can work it out.
FWIW, I went thru this with my Tylers - I was getting some piano notes, along with other instruments such as the clarinet, sticking out like sore thumbs in the upper mid range. A very narrow range. Initially I thought it was the Tylers, then I blamed the amps, ultimately what I discovered was that the utilization of KT88's in that particular amp (not in my other amps though) that was causing the problem. Put in 6550's and the problem went away. This also applies to small tubes as well. Now if you have changed your input tubes and no matter what kind you use it still is a problem then it might be your speaker location. Might be. But I'd be more willing to bet it was a speaker/amp interface problem than anything else. JMHO. Hope you can work it out.