Are you able to give a little more detail on "entertainment gathering"?

The music I have asked, you will mainly hear them in war like music, they generally have no lyrics.

However, given they are a form of orchestra, you may find a band who will perform them in an opera like setting, so would this be considered an entertainment gathering?

So entertainment sessions are those sessions where such events take place:
-Singing haram songs (love, sex, etc…)
-Singers performing

So that’s what scholars mean by entertainment gatherings