Fine recording! It took me a while to figure out there was a flute/piccolo playing along with him. I thought it was some sort of overtone or a recording anomaly...
There are a few of Mr. Brooks recordings out there. Here's "King Cotton March" by Sousa.
Thanks for posting this, Ian. Was any "processing" done to the recording? The presence of the banjo is outstanding. Unlike the sound of the banjo on many old records this sounds like a human being playing the banjo.