NRC Certificate for VocalBoothToGo More information NRC can be found in Articles on NRC Noise Reduction Coefficients Â Â Â Â Â Post Views: 1,564 Q) I am interested in your soundproof curtain. Our doorway is 65″ tall and 80″ tall . Can I use your curtain to soundproof adjoining two rooms instead of installing a double door? Q) Which type of booth do I need? A Vocal Booth or a Sound Booth?