Scene.background?

Hi, sorry for bother you again, I have been trying to make it work but still having problems.

I tried something like; var tx=new THREE.CubemapGenerator() and give me an error …

How can I apply this on this example? https://jsfiddle.net/jauregui/cbnmwgp4/4/
I’m trying to put the equirectangular to the scene background to the scene background…