Audio Asylum Thread Printer
Get a view of an entire thread on one page
|For Sale Ads|
In Reply to: RE: Outdoor Speakers Sound Degradation posted by jackwalton on April 14, 2017 at 09:43:16
I deal with loudspeakers, sound out doors at distances at work and can offer an explanation.
If you had a single very small driver, it would radiate as a "point source" and project a portion of a sphere forward. As you move away, the loudness falls off at the "inverse square law" or -6dB every time you double the distance. Also at high frequencies, there is air absorption which attenuates the high frequencies although at a hundred feet or less it is insignificant (a calculator below)
The problem is that if one has more than one source in a loudspeaker, one has an interference pattern when they are both radiating and in loudspeakers, one manifestation is that the spectral balance and loudness changes with distance.
On a larger scale, this inherent multi-source interference pattern is what gives concert line arrays "that sound", variable spectrum based on location and a limited working distance, it isn't a loudness issue, it's more of a spectral and intelligibility issues.
So, in general outdoors when the weather is good, is a more benign environment for listening, especially at the scale of home stereo as there are NO room effects and it is surprising what one can do outdoors even at the scale of a football stadium.
What scale are you dealing with?
Wow - thanks for the detailed reply, also to the other posters. In terms of scale I'm really just thinking "average backyard". I have no doubt I can find a setup that would sound great for my purposes, I'm curious about a discussion I had with a friend about outdoor environmental impacts. Assuming the speakers are a set variable, would a more "bushy" environment dampen the sound volume (break or absorb the waves) and would a pool for example cause sound to travel further?
I get that the actual impact may be very little to the untrained ear like mine, but in theory...?
Well, heck, Tom, I was hoping/expecting that you'd get into a little about temperature, humidity, air pressure, temperature inversions, bodies of water, etc.
tomservo knows vastly more about this subject than me, but I might be able to add a (hopefully) interesting little note. Several decades ago when I was much more energetic than now I had a pair of good 3 way d'Appolito towers with all Dynaudio drivers I had built for myself. Being aware of all sorts room effects problems I wondered how my speakers would sound If I set them up way out in my yard far away from reflective surfaces except the ground and an occasional tree trunk. Once I got toe in and listening distance optimized and got over missing various room resonances the sound was wonderful. Rather than speaking of outdoor placement degrading the sound I think of it as being a placement that improves the sound very much.
One caveat to the above is that the speakers were actively biamplified, and if I remember correctly I boosted the bass some in the outdoor setting.
The only acoustic down side to being outside is you might have to add a bit more bass but begin free of room effects can be wonderful!
Post a Message!
This post is made possible by the generous support of people like you and our sponsors: