Passover Before Instruments

Since the Passover was given and practiced before Moses commanded instruments and before the instruments of David, there doesn't seem to be any connection between the Passover and instruments. Christ himself did not use instruments in the Passover. The Passover was also given before the Levitical Priesthood was designed, so families could practice it without being separated Priests. Christ officiated in a sense without being a mosaical Priest according to Aaron or Levi. So the idea a separated Priest must lead the passover or Lord's Supper isn't really biblical.

This may be why Christian worship can be without instruments and without a separated priesthood. All Christians are priests to bring salvation to the world. We are separated from the world, not from ourselves. We are a royal priesthood.

Genesis 47:22 spoke of the priests of Egypt that existed before and outside the nation of Israel; the Priests of Israel were instituted later in Exodus 19 in a conditional promise for the entire nation which Israel did not meet, then God implemented a separated priesthood after the golden calf in Exodus 32.  There doesn't seem a requirement for Priests to oversee the Passover. Nor were there musical instruments used in the first passover. Instruments were not commanded until later.

Even the first instruments were used outside of actual worship. Like when Saul and David returned from battle and women went out to meet him, which was  not in worship. I Samuel 18:6  It does appear instruments were part of their society, but notalways in a positive way. Earlier at the making of the Golden calf it seems instruments were used in idolatry. So instruments were first used in Egypt with their priesthood and associated with false religion at times. After the Exodus Aaron called a feast with joy and party, which he had no right to call. The feasts of Israel were given later by Moses, Aaron had no authority to call the feast associated with the Golden calf. 

After Saul appeared as king women went out of the camp to meet Saul to celebrate. So, even if you find instruments in the old testament, they appear after the introduction of the Passover, often associated with false worship, outside the camp and not formal worship. They were afterward commanded to be used with sacrifices by the priesthood of Israel, but that law was done away at the Cross. Those instruments can't be associated with Christian worship.

The only commanded worship with instruments was done away at the cross, never to be forced into the Christian community, see acts 15:1-37, leadership was not to compel the keeping of the law. Acts 15:19 that we "trouble" not them, so it was official apostolic policy not to compel the keeping of the law in its various forms, including instruments and separated priesthood. Acts 15:24 explains the idea as "troubled with words", and in vs  21 it mentions preaching.

So it is against apostolic policy to "preach" to "trouble" christians to keep elements of the law of Moses.

We should also note David allowed all Israel to use instruments while moving the ark to Jerusalem, but after the death of Uzzah that practice disappears and instruments only appears with the priests of Levi.

Jesus doesn't seem to use instruments at the Passover.  So instruments were not universally used in all situations.

See Matthew 26:30