Great question. Just to be clear with your answer: the music being played here is by David with a harp. So we can kinda guess the type of music therapy Saul is getting.
With that said however, I also want to be careful with the fact that this text is descriptive not prescriptive. It is a recounting of what took place, not a teaching what kind of music should be played for one’s wellbeing.
In terms of genre of music, the Bible respect both, in your own words, the soothing and happy-clappy music. In 2 Sam 6:14, David was “dancing before the Lord”. I’m sure David is dancing to a music / groove / tune (I’m not a musician, forgive me), and it’s hard to imagine dancing “with all his might” to a soothing music.
And of course, the Lord also respect one’s preference of music and opinion on its benefit. I think every form of music has their artistic beauty we can all enjoy, as well their benefit to different situations too.
Thank you Jer for your music service and ministry to hospice patients, the world is definitely a better place, with musicians such as yourself. I can’t imagine the bland reality without music. May the Lord be glorified always through your music.