Amonia gas to get the smokey finish. Then oil.
The base i warm matte black waterbased paint.
I designed them and my friend who is a high school furniture carpenter teacher made them.
He is making a lot of «world class» DIY things together with a guy who do the engineering.
This is f ex a huge modified Klipsch waveguide with a perfect 1,5 inch throat (JBL beryllium) and synergy mkdwoofers. It have a nearly perfect polar plot.
I reccomend to make a profile to look at this forum thread:
Loftet – superlang byggetrad | Hifisentralen
What's the most suitable damping mat available in US for thin wall box? I just got a set of vintage 60's Jensen cabs with 12" Jensen Flexair unit (they claim 15 Hz fs) it is a 4 -way horn studio monitor ( closed box). There is no damping whatsoever in the cab and the speakers sound absolutely lovely. (I do use subs) I wonder if I'm going to ruin the sound of those boxes by applying a damping mat and some wading inside a close cab.
1" or 2" OC 703 duct board is current version of what Altec used, usually ~ loosely attached with roll roofing felt washer head nails and recommended on just one parallel wall: https://www.owenscorning.com/en-us/insulation/products/700-series-fiberglas-insulation
After WWII, cellulose before: https://lh3.googleusercontent.com/p...blBa0y09bUn4HbE6OCqe_Vx5TQg0bgqRPwcQZaGrpLP1w
After WWII, cellulose before: https://lh3.googleusercontent.com/p...blBa0y09bUn4HbE6OCqe_Vx5TQg0bgqRPwcQZaGrpLP1w