Whether rock wool can be used for sound insulation depends on the sound frequency you need to absorb in the room. Rock wool can silence mid-to-high end frequencies, but is basically ineffective for lower frequencies. Most sound problems start at the low end of the spectrum. If you are doing music, it is recommended that you run pink noise through the mixing speakers at mixing level (for example, you can use 82dBrms a-weight as a reference point for debugging), and use a frequency analyzer at the mixing position to determine which frequencies peak, starting from the lower frequencies. You need to first deal with the low-end frequency peaks (this will reduce the higher zero points) and work up along the spectrum. By dealing with the lower frequencies, you will find that the higher frequencies will handle themselves. If you need to absorb bass, then a better choice is a diaphragm absorber or resonator.
Gypsum board, rock wool board and other cheap DIY solutions cannot effectively play a sound insulation role. Another problem with rock wool is that its construction and installation are not simple. A professional construction team is required. Although rock wool boards have sound insulation effects, it still depends on what you need to achieve. We can also use foam boards for sound insulation, because foam can be used to suppress frequencies above 200 Hz.
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