My sister-in-law forwarded this website link to me yesterday.  I have no idea how she found it.
The webpage is in Czech so I can't read any of it, but the video speaks for itself.

http://www.bibri.net/2009/08/31/kapela-hraje-tak-dobre-jak-hraje-bubenik/

Note the microphone setup next to the tractor to pick up the exhaust sound.