Today, you may be hard pressed to find a Reformed EP Baptist COngregation. You will find many of them adhereing to the RPW, though non-EP.
In earlier years,
The London Confession 1689 says:
I. The light of nature shews that there is a God, who hath lordship and sovereignty over all; is just, good and doth good unto all; and is therefore to be feared, loved, praised, called upon, trusted in, and served, with all the heart and all the soul, and with all the might. But the acceptable way of worshipping the true God, is instituted by Himself,and so limited by His own revealed will, that He may not be worshipped according to the imagination and devices of men, nor the suggestions of Satan, under any visible representations, or any other way not prescribed in the Holy Scriptures.
V. The reading of the Scriptures, preaching, and hearing the Word of God, teaching and admonishing one another in psalms, hymns, and spiritual songs, singing with grace in our hearts to the Lord; as also the administration of baptism, and the Lord's supper, are all parts of religious worship of God, to be performed in obedience to Him, with understanding, faith, reverence, and godly fear; moreover, solemn humiliation, with fastings, and thanksgivings, upon special occasions, ought to be used in an holy and religious manner.
16. I Tim. 4:13
17. II Tim. 4:2; Luke 8:18
18. Col. 3:16; Eph. 5:19
19. Matt. 28:19-20
20. I Cor. 11:26
21. Esth. 4:16; Joel 2:12
22. Exod. 15:1-19; Psa. 107:1-43
Our church holds strongly to the RPW, but, as Matthew has pointed out, we are not psalm exclusivists. We sing selected hymns from the old Trinity Hymnal, the Gadsby Hymnal, and we sing Psalms from the Trinity Psalter.
Our non-instrumental instrument is a piano, which leads us in singing but doesn't do anything else.