Speaker replacement question

[poorbassist15]

I have a Behringer BXL900 I've been trying to get rid of because the speaker sucks, but, since no one wants it, I was thinking about giving it another chance. I decided to replace the speaker a few weeks ago. I was thinking of an Eminence 12", but the amp is 4 ohms and the speaker is 8. I'm confused about this, will the speaker work, or do I have to get another one?

 

[Hollywars]

It will work, but it will get less power.

 

[poorbassist15]

Thanks, I know now why the speaker sucks. It's rated at 70 watts, and the amp is 90.