4 ohm. > 89 db.

Is your question; "Are there other loudspeakers out there"?  Yes, there are. 

I agree with @russ69 -- not really sure what your question is about. There are a LOT of factors beyond impedence and sensitivity to consider when picking a speaker.  The first question -- have you heard these?

I agree with those above. What are you getting at. What system do you have?
 

I have Sonus Faber Amati Traditional 4 ohm 90db sensitivity. I think most Sonus Faber are about that.

Or do you want them to play that loud… mine will.