Yes, I have a code for everything CA70. BG70, ST70, etc. These are some new broadband bass traps built by Alan Ulrich (drummer in The Moto-Wrays, woodworker, all-around great friend) and myself. The design is an amalgam of most online designs you’ll find via pro audio and acoustics forums. They are standard 2′ x 4′ x 6″ frames of 3/4″ Chinese birch 11-layer ply. The holes are 3 1/4″, 8 on either 4′ side. 96 total. We used three (3) 2″ batt-panels of Roxul Rockboard 60 (opted for this rather than fiberglass ala OC 703) for the inside and black weavers fabric for covering. They are also fitted with some ersatz FRK (contractor paper) on one side so they have dual function; these are all set to the broadband side for now. We made six (6) in all and they weigh in at 42.6 lbs/19.4 kg each. Solid.
Also seen here: some early tests of the room untreated and treated. Note: I have no cloud absorbers on the ceiling at all. I may shove the rest of the Rockboard up there. But the room is problematic as you can see. I’m guessing due to the room modes (re: size) I cannot ever fill that dip around 147 Hz = too long and too wide a room. I officially start my “Build ST70″ fund today and any acoustic/audio savants that want to chime in are welcome because I’m no expert. Things are sounding better though. In the graph, red is untreated and green is treated; the room is still enormous. Thanks AU for all your help!