Railroads have changed alot in the last 15-20 years since I have been observing trains. There are more of them in some places, less in others, but one of the biggest cahnges I've noticed is in the newer locomotives.
The Dash 8's are more quiet than the Jeeps or SD40-2's of the previou decades. Sometimes they are quieter than regular automobiles, only a slight gurgle even at some higher speeds. They don't even look like train engines to me but more like semi trucks on steel wheels.
Anyone else notice this?