between floors speakers

[Swagger II]

Hey guys quick question:
trying to install some speakers in the ceiling of an office, which which happens to be the floor for the 2nd story. because of the type of construction, there is only going to be about 1.5'' of rigid foam insulation between the speaker housing and 2nd floor plywood...

(Im a newbie here, and trying to post a link, need to get post count up, message continues below in next post...)

 

[Swagger II]

my concern is with sound transmission into the 2nd floor, as you may have guessed already. Given the circumstances, what is the best way/material to insulate the enclosure to block sound transmission?

 

[Swagger II]

I was thinking to use some MLV and wrap that around the enclosure and caulk all gaps...

 

[annunaki]

I would recommend using a Roxul 80 product or finding some Thermafiber Versaboard 80. They are 8lb per ft^2 in density and do a great job with sound absorption. You can also caulk seams etc but avoid using products that will eat too much into your available cubic volume for the speaker itself. That is where the Roxul/Thermafiber options work well since they are "breathable" for the speaker.

 

[TheWarrior]

I did a review of Triad Inwall loudspeakers: https://forums.audioholics.com/forums/threads/triad-inwall-bronze-lcr-4.110548/

In there you will see that my 2x4 wall has no insulation, and one of the speakers even backs up to a fiberglass shower unit. Despite that, I think I measured a full 20dB attenuation in the bathroom.

In addition to what was said above, you will also want to consider what is on the floor on the 2nd story. If you find sound leakage after trying the other recommendations you may want to explore adding a thick pad and carpet.

What loudspeakers are you using - Are they sealed, or do they have an open back? If open back, and you still have trouble with too much sound leakage, you may want to consider a model with a sealed back.