[davidc1]

Hello all,

I have purchased the drivers and cabinet for an LRC, but will need the diffraction foam for around the tweeter. Does anybody know a good source? Or, more importantly, the specs of the foam. In this day and age, it's easy to get some foam, but there are many, many types. Can anyone help?

[GeorgeAb]

Hi David,

Brian used a spun fiberglass insulation for the major bass interior.  Likely 700 series owens corning. I just use poly fill. For the small enclosure behind the midranges in RM-30/40 etc there is a white poly fill. I forget if the LRC has a small enclosure for the mid ribbons or not.  If there is a small enclosure check the caulk where the wires go in and reapply if necessary so it is sealed.  Many have been lining their cabinets with an acoustic foam material that you cut and it sticks to inside of cabinet https://www.parts-express.com/sonic-barrier-1-acoustic-sound-damping-foam-with-psa-18-x-24--260-525 and then providing fill.  I used 3/4" on my RM-V60, but not on my LRC. I just used the white poly fill on my mid-bass cabinets at it easy to get at parts express. I have a little over a pound of the white poly fill https://www.parts-express.com/acousta-stuf-polyfill-1-lb-bag-speaker-cabinet-sound-damping-material--260-317 left over from a project (should be close to what you need) so give me a shout out via PM and I will send for shipping cost. Manufacture recommends 1/2 lb. of damping material per cubic foot of enclosure.  Also, some folks go to Walmart and get mattress padding. My old Kef 103's came from the factory with that material in them.