May have been until recently the Dominie T1 (HS125 200 Series). Two Vipers in close formation made a hell of a noise. In recent years we were theoretically banned from many European civilian airports. We were often asked for our Noise Certificate? The Dominie noise was never certified at any level apart from "Very Noisy"
We talked our way into many places such as Milan Linate and Paris Le Bourget but very rarely welcome back until their memory faded as to how many noise complaints we generated.
All that noise for just over 6000lbs of thrust!!!