952 Studios Construction!

[Starlight]

John Brandt has a PDF where he walks you through making a door. I am not suggesting you start afresh but you may be able to glean something that would help you beef up your existing doors, particularly adding thickness with sand. If you beef up your doors that may reveal the relative weakness of your existing door seals.

https://jhbrandt.net/wp-content/uploads/2022/11/Building-Studio-Doors-1.pdf

Looking at your photos, my thoughts are whether adding a second door to the outside of the live room frame (hinges on the same side as the existing door) would even be possible as it would be an obstacle with the other doorway so close.

My experience of doors is such that I am persuaded that door seals do a great job in creating an airtight seal and increasing isolation such that it justifies the work, but the real reduction in sound getting through is when pressure can be exerted on the door to actively press it up against the frame, compressing the door seal.

Additionally, do your doors have a good seals underneath them? That would involve having a step (a trip hazard) so that the bottom edge of each door closes up against the 4th side of the door frame. I think there might be room for improvement in your existing door thresholds.

[eightamrock]

Thanks, Starlight. I do have both a drop seal and good threshhold seal. The main issue I think is that the door needs more mass. I can clearly hear resonance of the instruments through the center of the door it self. Of course that is absolutely even worse at the perimeter of the doors, but I am thinking if I add sand or even a sheet of 3/4" MDF to the door, I can make a second jam and have added mass. That PDF was a fantastic resource, thank you!

[Starlight]

Steel sheets (7,850 kg/m3) are simpler and thinner than sand and 3.5 times the density of MLV (2,200 kg/m3). Adding a thin sheet to the jamb side of each door, say 3mm (1/8") would add in the region of 40kg (88lbs) to the mass of each door, subject to your doors' dimensions. Check whether your door hinges are up to bearing the extra weight; I suspect (which is not a scientific measurement) that you will need an extra hinge beneath the top one on each door.