You might find mixing some mariachi trumpets in with the regular trumpets gets you closer to the old brass band sound. One of the signature sounds of a brass band is that cornet vibrato that is SO different from orchestral and jazz trumpets!

And the rest of the brass is very muted (dull) compared to orchestral and jazz horns other than the trombones. Maybe EQ out some high end?

I played trombone for years in high level brass bands, I just love that sound! But it’s close to impossible to get on an arranger…

Loves me some Black Dyke Mills Band, and Brighouse and Rastrick! Ooh aye, ecky thump!