I have just found this very interesting article on a Arnold Jacobs masterclass. Is there any Arnold Jacobs students out there? If, so have you any interesting stories about his lessons or philosophies? http://www.windsongpress.com/jacobs/arnold jacobs masterclass to the international trumpet guild.pdf (The link might come up as page not found. However if you click on it, it should work). This link might start up some new controversies within the whole air pressure discussions.