The No.1 Website for Pro Audio
 All  This Thread  Reviews  Gear Database  Gear for sale     Latest  Trending
Thinnest effective and sturdy gobo design?
Old 24th June 2019
Thinnest effective and sturdy gobo design?

Hi all, sorry for yet another DIY gobo thread.

I have a pair of 4'x6'x4" gobos on casters. They are a simple box frame, pocket-screwed, with 4" of 703 inside and an 1/8" BAD-type panel of plywood on one side. Functionally and structurally, they work fantastic. I use them primarily to tighten up the room sound, and they do well at helping isolate instruments.

I want to build another gobo and I'd prefer a) the width to be 4" or less, and b) both sides to be absorptive. This gobo's primary use would be to help prevent mic bleed. I don't have another BAD panel (and swore never to build one again ), but the sheet of plywood was instrumental in providing structure for the gobo itself.

My question: is 2" 703 | 1/8" hardboard/pegboard | 2" 703 enough for isolation help and decent absorption? Do you think 2" of insulation and a wider barrier would be a better way to go for a thinner gobo at the price of a reflective side? Is there a layout that would be better? I know the classic BBC design had 2" of foam but was also faced on both sides with reflective panels.

Thanks for any advice!
Old 27th June 2019
gobo bump
Old 1st July 2019
Here for the gear

What about a torsion box construction for a gobo panel that's absorptive on both sides? its frame would provide rigidity/structure that you could cover with fabric of your choosing. Another option would be to build a plywood box consisting of a series of cubes like this:
Old 1st July 2019
Torsion box is an interesting idea, though seems like a ton of work. Are you suggesting filling each square in the frame w/ insulation, or having insulation on either end?

I ended up building an identical gobo to the one I had before, though I’m also thinking of building a few “screens,” BBC style.
Old 4th July 2019
Gear Nut
Ultrasonic_UK's Avatar

How robust does it really need to be? For home use I've made a free standing gobo-style panel which is a single piece of 4" thick Rockwool just supported around the edges by a frame like in a regular panel. I'm not sure if I'll be keeping it long term so it only has a cheap fabric covering for now, but it looks like this:

I'd have made the legs/feet more substantial if it was going to be moved around regularly but I'm not sure that the layer of wood proposed in the middle of the panel is really necessary, and performance would be better without this.

Edit: I chose to leave the frame visible as I quite liked the look but if fabric was wrapped over the frame like on a standard panel then this would of course hold the absorbent material more securely in place. Not that there is much danger of mine falling out of the snug fitting frame.
Old 12th July 2019
I like that idea…it's similar to how I build my acoustic panels, just larger! Although for my specific use it's probably not substantial enough.

I ended up building one with 4" of 703 and pegboard on one side; I figured I'd keep the formula going. I may build a vocal "screen" for some projects coming up (BBC-style) where my curiosity about 2" of insulation and thicker mass (MDF?) is still high.
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.

Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump