TromboneChat

I'm not going to be able to see most of my family this Christmas so I'm thinking of recording them some trombone christmas tunes. I'm hoping this will make them smile, or at least be glad they don't have to share a house with me and listen to me all the time.

I have The Official Real Christmas Book https://officialrealbook.com/real-books ... s-clef-ed/ which has some good tunes in it. I'd like to compose a simple second part to the tune I decide to play (I have ambitious plans to do more, but will start with one).

My music theory knowledge skills are pretty much close to nill. I know what a chord is, or at least I think I do.

Does anyone have any advice of how to create a really simple second part that I can record as a backing part?

I'm going to make an end run on your question. Why not give it a full accompaniment. I use Band in a Box. You can choose your background, type into it the chords you want to use, and you can control the tempo and key. Easiest way to get a much "professional" accompaniments quickly , and with little work, that I know.

I'm really early on this learning curve as well, but here are a couple ideas.
1 - Canadian Brass "Flex for Two" arrangements https://canadianbrassstore.com/christma ... -download/.
2 - If you've got the chords in the reel book, have the second part play the root and fifth of the chords. If measure 1 has a Bflat, play Bflat. If measure 2 has an F, play C. It takes some iteration because sometimes the root of one chord is the same as the third of the next one. But it's hard to go wrong. If you want to sound more jazzy, use the third and the 7th of the chord instead of the root and the fifth.
3 - Band in a box or iRealPro have chord backing tracks. I like playing along with iRealPro. I've not tried to export the backing track into recording that overlays with me playing, but I'm sure it can be done.
4 - When I lived in the UK our village brass band would warm up from the Salvation Army red book. I think there's a version for Christmas tunes? It would take some digging and you might have to transcribe some of the parts for trombone.

If it's good voice leading you want in another voice, the 3rd and 7th are the go-to choices, regardless of genre (modal music discounted). An old rule: when voice I moves, voice II takes slower countermelodies, and vice-versa.

Thanks everyone. All this advice is really good and just what I was looking for.

Richard, here's one example of the carol books I mentioned. There might be a UK distributor for the books: https://www.hickeys.com/search/products/sku011285.php. The Salvation Army Carolers' Favorites is here (US supplier again): http://shop.salvationarmy.org/ecom/prod ... lang=en-US