Some opponents on using instruments say that instruments are "devilish". Well, they can be. But when it comes to communicating, nothing can be more "devilish" than human tongue. It's not about the tool, but how it's used. Pure heart speaks with pure tongue and plays instrument with pure touch. And, instrumental music can't lie. It's always naked before the listener. What you hear is what it is. If what is played on an instrument sounds divine, it is divine.
Some say that instruments are only mentioned in Old Testament (even though they are not, since use of psalms is instructed in New Testament, and with it, use of instruments is instructed too), and ask if we should also sacrifice animals, as sacrifices were instructed in Old Testament too. Somehow, playing an instrument from your heart, gracefully to God, is the same as slaughtering an animal over altar.
Anyway, there are a lot of arguments that show that instruments are allowed in worship. But it's tiring to even think about them. It tells us something that this is an issue in the first place.
By the way, basically all great composers are instrumentalists. If you want to write choral music for four voices, for example, you sit at keyboard instrument or take stringed instrument in your hand, and compose on it, so you can hear it - and shape it - immediately. Sergei Rachmaninov, one of the great Russian composers from the last century, who wrote Russian Orthodox Liturgy (for choir), was virtuoso pianist. If instruments are good to create God worshipping music, they are probably good to perform it too. Bach believed that, thankfully. I have searched for information about famous Byzantine composers from earlier times, and couldn't find if they did or didn't use instruments for composing their choral works. But it's safe to say that if they didn't compose layered choral music with the help of an instrument, they probably didn't compose the best music they could. At the very least, you need some instrument to get the intonation right, unless you have perfect pitch (which is a rare physical talent, and God worship doesn't depend on a rare physical talent). So, just a quick glance finds instrument as seed for singing worship. As such, it's significant part of worship from the beginning.
Finally, a word about performing. In my view, if instruments are played for communal worship, players shouldn't be at the center stage, for everybody to see them. Worship is not about the players, so they should be, preferably, out of sight. On balcony or obscured in some other way. They are there to serve worship, gracefully, not to be worshipped themselves.
