Yeah, this morning just before 4, I was awakened by a large "thud-boom" sound. I thought it was a sonic boom that's how loud it was! I woke up my wife, and she was oblivious to it. I got out of bed to see if my son had fallen upstairs or something. He was fine. I turned on the scanner to hear the police being dispatched to a "burglary in progress, someone in the house" and to a "sound of a helicopter crash"!. Earthquakes in northern Illinois are really rare, and from what I gather, the loud boom sounds are strange and not typical to earthquakes. I don't know about this since this is only my second earthquake I've ever experienced in my lifetime. I never felt any shaking, but my daughter texted me at 4:30, and she said her house was shaking since she live about 8 miles from the epicenter and things were rattling.
Steve F