No, the additional 600 sounds make the difference. I think the identical 1,100 sounds really sound identical. I'm not sure if there's a noticeable difference in the effects, I haven't noticed any, but I don't think there's a difference in the sample quality of those 1,100 sounds. (Small surprising exception: the BK-7m even has one tiny advantage: it has two or three so-called "Natural sounds" - a simpler type of "SN" sounds: at least one sax and one trombone. Their pitch bend reacts with natural scales. This feature has been eliminated in these 2 or 3 sounds in the BK-9 probably due to the 22 SN sounds - however these 22 SN sounds don't include such a trombone and a different (worse!) sax.)