Many use the harps of Revelation as precedent for any instruments we want to bring into worship. To them it is a general precedent for any instrument. It really shouldn't be used that way since the instruments mentioned are specific. Only harps. Plus each of the 24 Elders only had harps. There was no diversity in instruments leading anyone to say all instruments are approved. Since they all used harps they didn't take steps to introduce other instruments. It is precedent for sticking with specific examples, and not broadening the scope.
So, pianos and organs and bands of all types wouldn't have been used by the 24 Elders. It would have been viewed as sacrilegious by them in my opinion.
Like Moses, who only commanded trumpets for the children in the wilderness, they were specific. Then David and the Prophets introduced specific instruments for the Temple, they were specific in time, place, persons playing, and purpoce, Revelations instruments are specific in the same way.
Specific does not qualify as general precedent. People use the example incorrectly.
Later in Revelation it mentions the instruments used within the Harlot realm. We should also realize the harps of the Elders may have been symbolic of the heart, an instrument of God.
Others like Max Lucado taught that instruments were a natural part of society and should be viewed as acceptable without commands. Yet this is disproven by Moses who had to command trumpets and order their usage, and David who brought in instruments not previously used, then order them.
Lucado and others were simply incorrect and had fallible reasoning.