Trumpets are horns. A bigger mouth on the horn means that slightly lower frequencies will be amplified more. It also means that the higher frequencies will become more "directional". Like any other single aspect of the horn, when pulled out of context, it is USELESS. We need to judge the entire product. Most of us have no where near the knowledge to base a decision on anything that we measure or read. We dummies need to PLAY THE DAMN THING to know better.