Robert Lamm (1944 - ) is an American singer, songwriter and keyboard player who was one of the founder members of Chicago Transit Authority in 1968.
Chicago, as they came to be known, was a big band with a large brass section. Sue and I loved the sound they made, in fact I booked an Edinburgh band who played the same music for our dinner dance when we opened the Ulstein Scottish factory. Unfortunately the majority of guests did not seem to like Chicago style music!
The track below is possibly Lamm's most popular track from their first album called Chicago Transit Authority.
Another popular hit song of his was '25 or 6 to 4'.
Robert Lamm's extensive discography can be found here.