No, and apparently no rubber membrane or green glue between the layers of sheetrock. I didn't hear if the two layers of sheetrock were the same thickness. If so, you can stop different frequencies by using different thicknesses. And I would've also plastered and sealed the first layer of sheetrock before adding the second.
Yes it will. I work for a national house builder in the UK and we fit resilient bars to ibeams and use only standard 15mm plasterboard,one sheet, not double boarded and we get great results. If you use soundproof board though be aware that it is heavy, 44 kg per board. Use a board lifter.
@@Landofhopeandglory575 Long shot of a reply after 3 years, but would you say resilient bar + standard sheet gives comparable results to lath and plaster when factoring in airborne noise?