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<blockquote data-quote="Ivan Beaver" data-source="post: 58047" data-attributes="member: 30">Re: Funny specs provided for show I&#039;m doing this weekend.Watts does not say a whole lot.&nbsp; While 70dB may not seem to be very loud-it depends on how far the loudspeakers are away from the listener-the sensitivity of the loudspakers and so forth.When you start to look at distances of say 1000&#039; can result in losses of at least 50dB-some football stadiums have listeners further way than that from the loudspeakers.&nbsp; Once you throw in air absorbtion-the highs could lose another 50dB.So you are looking at up to 100dB of loss at that distance.We don&#039;t know-but 40Kw may not really be all that loud where it needs to be.&nbsp; 40Kw is 46dB of gain.So if you look at a little bit of &quot;math&quot;- to provide 70dB (we are not assuming any headroom here-which will require more output)&nbsp; + 100dB loss=170dB.&nbsp; Take away the 46dB gain in power and you have 124dB.&nbsp; So the speaker system should produce 124dB with 1 watt of power to meet the &quot;minimal spec of 70dB @ say 8Khz.Of course at lower freq the air absorbtion-or in a more humid climate- will be less-AND there will be a lot of other factors to take into consideration-but it is always a good idea to do a little bit of quick math to see if the system will perform as desired.</blockquote>

[QUOTE="Ivan Beaver, post: 58047, member: 30"] Re: Funny specs provided for show I'm doing this weekend. Watts does not say a whole lot. While 70dB may not seem to be very loud-it depends on how far the loudspeakers are away from the listener-the sensitivity of the loudspakers and so forth. When you start to look at distances of say 1000' can result in losses of at least 50dB-some football stadiums have listeners further way than that from the loudspeakers. Once you throw in air absorbtion-the highs could lose another 50dB. So you are looking at up to 100dB of loss at that distance. We don't know-but 40Kw may not really be all that loud where it needs to be. 40Kw is 46dB of gain. So if you look at a little bit of "math"- to provide 70dB (we are not assuming any headroom here-which will require more output) + 100dB loss=170dB. Take away the 46dB gain in power and you have 124dB. So the speaker system should produce 124dB with 1 watt of power to meet the "minimal spec of 70dB @ say 8Khz. Of course at lower freq the air absorbtion-or in a more humid climate- will be less-AND there will be a lot of other factors to take into consideration-but it is always a good idea to do a little bit of quick math to see if the system will perform as desired. [/QUOTE]

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