AIA Small Project Design (SPD) Knowledge Community supports, celebrates, and promotes small projects by engaging designers and the public.
You might look at "Acoustiblok"
We used it on a patio and owners said it worked great.
William Peck, AIA
William Peck & Assoc., Inc.
a r c h i t e c t s
105 W. Main St.
Lewisville, Texas 75057
Office 972.221.1424 ext 106
One of the issues you will be facing will be the physical characteristics of the space. Obviously, a 6'-6" fence is not going to block noise to second (or more) floors overlooking the space. Also, if the space is surrounded by taller buildings, the sound will reflect off of those as well and likely circumvent the wall.
There seems to be all whole lot of confusion in this thread regarding sound absorption vs. sound attenuation.
James G. Richardson AIA LEED-AP
Richardson & Associates Architects
210 Noble Avenue
Montgomery, AL 36101
There are ways of reducing the "loudness" of the sound/music/live performances/etc. Maybe you might want to consider this, as opposed to an architectural solution.
If you've ever heard a car with a loud stereo, you will relate to this. Short wavelength sound (higher pitch/whispers/tapping) can in fact be dispersed/absorbed/masked/deflected with fairly thin materials,; car windows, sheetrock, thick hedges. Landscaping and walls do a great job at this. It's the long wave length (bass beats/vibrations and lower "notes") sound that is nearly impossible to control. When a car playing loud music (with the windows rolled up) passed by, it's those pesky low wave sounds that you hear and feel. Think "thump, thump, thump". Airborne low wave frequencies are extremely difficult to attenuate.
However, you might want to look into "sound pressure limiters" on the sound system which limits the amount of low wave frequency pressure and vibrations. They basically eliminate the "head pounding" effect of sound. This is a special piece of equipment that filters out the lowest end of the sound but leaves the sound still intelligible. In a restaurant setting, most people begin to amplify their own speaking when they can't hear intelligibly what other people are saying. A natural response. Sound pressure limiters just remove the "loudness" (pressure on the ear) that causes this to occur.
I'm not recommending any particular manufacturer, and this is such a common problem that there are tons of companies in this business, but here is an example of one with an explanation of what it does. https://fitnessaudioshop.com.au/products/gov-nor-sound-limiter
Best of luck with this,
Mark Forth, AIA, NCARB
Sent from Mail for Windows 10
I know of no evidence that landscaping (plantings) will have any measurable effect on sound absorption. In our experience, even a fence, mass wall, or a barrier incorporating sound absorption material will not provide a sound level reduction more than 5 to 10 dB. Before-and-after testing test with a meter might detect a reduction in sound level, but your neighbor's ears will still hear the music and will likely not be appeased by attempts to block amplified music with a barrier.