I was playing around with my older Holton this past weekend. I was having one of those days where I could get a nice tone with very little air. the trumpet had a really nice "core" sound. I notice horns brighten up when I accerate the air flow and also when I play louder. Some horns seem to be more sensitive to this. Some horns take alot of work to have them do it as well. I have known this somewhat for years but this time the core sound seemed alot stronger. Can anyone explain to me in layman's terms why or how a trumpet works like that?