Based on the early conversation between the youth and the loud soldier, what irony does there seem to be in the description 'loud'?

Continuing to call Wilson the "loud soldier" is ironic because he cares for Henry with tenderness and concern.

At the fireside the loud young soldier watched over his comrade's wants with tenderness and care. He was very busy marshaling the little black vagabonds of tin cups and pouring into them the streaming iron colored mixture from a small and sooty tin pail. He had some fresh meat, which he roasted hurriedly on a stick. He sat down then and contemplated the youth's appetite with glee.

The youth took note of a remarkable change in his comrade since those days of camp life upon the river bank. He seemed no more to be continually regarding the proportions of his personal prowess. He was not furious at small words that pricked his conceits. He was no more a loud young soldier.