My ceiling is low... VERY low... we're talking barely 7 feet. It's all I have so I must make due. It CAN work if treated properly. It's a drum room so cymbal content is the biggest offender close to the ceiling.
Needless to say, I wish to make the ceiling sonically disappear. This means I need absorption that has zero reflectivity properties, especially in the upper-end.
The ceiling itself is dual 5/8" sheetrock, a 9" air gap filled with R-15 batt insulation and then a dual plywood floor above. I'm sure a certain amount of low-end will pass through the ceiling to the floor above, so in theory, I may not need to worry so much about trapping low-end at the ceiling. I will of course have good bass trapping inside the room itself at the corners, side walls to help with low-end in general, etc.
Since the ceiling is so low though, I of course wish to use the "thinnest" trapping on the ceiling as I could possibly ever get away with while still getting as close as possible to making the ceiling "disappear". I know, I can't have my cake and eat it too... but I'm gonna at least TRY
I know some high-end bass traps advertise that they actually reflect a bit of upper-end frequencies as to not make the room so dead and lifeless. In normal applications, this sounds like a great concept and I'm sure it works very well... and I plan to use such traps on the side walls.
But for the ceiling, I'm thinking I want ZERO reflectivity, especially at upper frequencies. AND... in a PERFECT world, I'd use a trapping material that is no thicker than 2 inches... ok, maybe I need to go to 3 inches... 4 inches would really be pushing it.. certainly cannot be thicker than 4".... but 2" - 3" preferred... otherwise I'll darn near be scraping my head.
Now, I'm not a fan of acoustical foam (like Auralex, etc), I generally do not like the response of this stuff, HOWEVER, I'm wondering if acoustical foam might be the best thing for my ceiling needs here. Foam will eat up ALL the upper-end and should in theory give me a totally dead response, even at just 2" or 3" thick. I do realize though that it will not perform well for ugly lower frequencies, but again, I am hoping that the ugly low stuff might just pass through the sheetrock to the floor above... it's not like the ceiling is made of 12" of concrete or anything.
Plus if I have GOOD bass trapping in the rest of the room (like RealTraps, GIK traps, etc), it will help eat up any extra low-end that might be bouncing around the room in general.
What do you guys think?
I know in general that most of the forum people here are anti-foam, and I understand why after having used it a few times.... BUT, I wonder if foam might be the ticket in this application.... key terms: thin as humanly possible, zero upper-end reflectivity, max upper-end absorption.
Here's a question... what would be better:
- 2" of SOLID acoustical foam (not wedges etc, but solid) - Note: 2" of SOLID acoustical foam can be achieved by taking two 2" thick wedge foam panels and mating them together, result is 2" thick foam with no wedges... for max performance with limited thickness
- 2" of rigid 703 or 705 (or professionally made traps made from such)
- Any other better options?
My understanding is that some 703 / 705 type traps will have some degree of reflectivity which is why I am thinking they will not be good here. Any upper-end reflectivity at ALL will make the low ceiling height sonically detectable on a recording.
Thanks
