Instruct: Classify the given review into positive or negative sentiment.
Query: Something is missing...

I bought Blue Man Group's second CD called "The Complex" before I bought this one. The big difference between the 2 cds is that The Complex had vocals on most of the songs. Without the vocals, like this cd, I find Blue Man Group kind of boring. I guess when you're watching their music in a live show, you get into it, but just listening to it gets boring without more mental stimulation such as vocals. I do have to give Blue Man Group that their rythms on this cd are very good.