Do you think is wrong to worship God using animal sacrifice as David did? if no why doesn't anyone do it? if yes, what is the difference in playing musical instruments as David did, and not all other worship David did?
Nowhere is it recorded anyone on this earth in the first century church using mechanical musical instruments... for you to add it on your own is will-worship :
Col 2:23 (KJV)
23 Which things have indeed a shew of wisdom in will worship, and humility, and neglecting of the body; not in any honour to the satisfying of the flesh.
Why would we use an animal sacrifice today after the sacrifice of Christ? It is finished! No further sacrifices needed (Hebrews 10:9-14). In regards to your argument about no musical instruments used in the first century church, no church in the first century owned its own building, but met in homes or in other public places. No church in the first century had pews. No church in the first century had electricity or sound systems. The Bible never mentions whether any church service included a time of announcements or a Sunday School. We have all of these and I am convinced that they are acceptable. I assume you have none of these in your church.
Practices of the church fit into three categories: the scriptural, the unscriptural, and the non-scriptural. The scriptural were those things that we are commanded to do in the Bible and we should always do those things. The unscriptural are those things we are commanded not to do and we should always avoid these things. The non-scriptural are those things that are not spoken of in the Bible. Those things that are non-scriptural must be examined in the light of scripture to see if they fulfill scriptural goals or not. If they do, they belong with the scriptural. If they do not, they belong to the unscriptural. For instance, the New Testament does not mention the Sunday School since it is a much later invention. However, if the Sunday School is properly used to teach the Bible (a scriptural command) and to reach the lost (another scriptural command), then the Sunday School becomes a scriptural practice.
Musical instruments, if used with care, can enhance the singing of praise to the Lord. That was seen by the Christian church that split from the church of Christ. Musical instruments were obviously considered a help to praise in the Old Testament and in heaven. It seems strange to say that something God thought was a blessing in the Old Testament and is considered a blessing in heaven is an evil in the New Testament church. The burden of proof would lie on you and not on me.
As I previously stated: Ephesians 5:19 says "..speaking to one another with
psalms, hymns and spiritual songs.." and correspondingly Colossians 3:16 says to, "..admonish one another with
psalms, hymns and spiritual songs." The word "psalm" in the Greek dictionary, definition (#5568):
"A set piece of music, i.e. a sacred ode (accompanied with the voice, harp, or other instrument)." The root word of psalm is "psallo" which means to means "to twitch, twang or pluck," such as pluck a string of a musical instrument.
If the church of Christ (or any other church) wants to leave out musical instruments in their worship, that is their prerogative. But I don't believe that it's right for them to judge and condemn everyone else who chooses to use musical instruments like David did, as the angels in heaven do and as the apostle Paul instructed.