Hello people! In a previous incarnation I was planning on buying a bunch of realtraps for my space in NYC........... but now I am seeking refuge from New York City in Nelson BC Canada and my resources have dwindled. I have relocated my audio gear to my brothers garage. The sound is OK for recording my cello but a little too much slap back with a cement floor and plywood walls and a wooden garage door. Looking to build panels to kill the reverb a little (and help with the first reflections for mixing) I can only get rockboard 80 2'x4'x2" here (remote BC interior). Planning on building 4" panels with 2 2"pieces of 80 in a frame and mounting them 4" from the wall. I would prefer rockboard 40 but i really can't seem to get it without jumping through hoops. At 8 pcf will it work ?? Or should I jump through hoops to get rockboard 40? The online data does not give specs for Rockboard 80 at 4 inches and I know more depth does not always mean more performance when we start getting into higher densities of material. If it really doesn't translate into a big difference I won't worry about it. If the cognoscenti of the audio world say it will all come out the same in the wash I won't worry about it. But I am a little out of my depth with the world of panels and i am trying to pull off a magic trick here before the cold comes! i would hate to do all this tracking and realize I should have used different panels. Thanks Rufus
If this is a temporary situation and you're mainly recording and not setting up a mixing room, I think the LF problems you will address with thicker 4" panels are not your biggest enemy. 2" panels will address the slap and other reflections and if your mike is reasonably close, (one rule of thumb: mic distance=size of acoustic body so for cello ~30" but closer or farther is not wrong either). Closer will help minimize your pickup of room reflections. Moveable panels on stands work great for recording too so you can place them around your mics and instrument and change acoustics on the fly etc.
One thing that can mess up your recordings is attempting to get a "room sound" in your recordings from a bad sounding room. You're way better off recoding close miked and adding digital reverb later than recording a terrible room sound which cannot be removed later.
For room acoustic treatment in general, 4" or thicker is always better for the LF performance but when cost comes into play, you're better with more coverage at 2" than less coverage at 4".
Oh, I almost forgot to mention that if you space your 2" panels 2" from the wall, you will get effectively the same LF performance of a 4" panel mounted flush against the wall.
I will be doing a fair amount of mixing so i will set up a cloud and side panels and a rear panel as well on a stand. It won't be that much more energy to set up 4" panels 4" from the wall......... the question I am really wondering is wether the rockboard 80 at 4" would work or if it is too dense or effectively the same for my applicationas as rockboard 40. Will the 80 work or is 8 pcf too dense? I am assuming it is not that different. Owens corning 705 is 6pcf ....... so I was thinking we are in the ball park...........but perhaps it is too dense? This is above my paygrade to figure out. So hoping for those smarter than myself can advise. Is it worth locating Rockboard 40 or can I stay with the readily avialble rockboard 80?