Gargoyle mades his point rather effectively. I get it now, they played trombones.

There's even a FAQ site about Moravian trombones:

http://webpages.charter.net/gmtc/GMTCFAQ.html

Gargoyle asked, 'Can you imagine the sound of 50 trombones and ONLY trombones?'

Well, I can, because once I went to a party where two skilled trombonists (members of the symphony) played background. I was quite surprised at their skill and the beauty of the music. It was obvious that modern music doesn't give a trombonist a chance to show what she can do.

However, the two of them were at the limit of what I could stand for volume. If there were fifty trombones, they would have to be outdoors and I would have to be able to move away as far as I wanted.

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I used to attend a church (built 1922) which had two arched niches on either side of the choir loft. I've learned that these niches were originally (say 1600) for brass players, such as the town waits, who would play on feast days such as Christmas.

Clearly brass instruments, which we think of as expensive, hard to play, and unusual, were much more common in the past.