As someone who has been going to shows in Denver for the past 10 years a lot of singers have trouble with the high altitude and they have trouble with their voice sometimes, so if the recording is from a Denver show that's probably why his voice sounds rough, I wouldn't know though because I didn't sign up for this record and can't listen to it, but thought I would share my opinion on the topic because i am bored. Also I missed that show and regret it