The answer is really quite obvious if you've ever heard a British brass band live - even the relatively small brass section in a symphony orchestra can completely dominate in terms of volume. It was established in Goldscheider v Royal Opera House that a typical brass section can achieve peak sound pressure levels of 137dB(A) without any special effort.
If a brass section give it the beans, then it's literally like standing on the deck of an aircraft carrier for anyone sat in front of them. You can feel your eyes vibrating in your head. You need a lot of string players to even hope to keep up with that.