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warbleed apparently said double woofers double power is 6.

and geolemon has said exactly what I am saying.

the laws of physics confirm my theory, and untill someone explains exactly what its a 6 dB gain, I still say it is impossible. I am pending and explanation from warbleed.

so you have 400 watts on one sub. doubling power DOES add 3db becasue it pushes twice as far. (assume 100% efficiency)

if you just add a second sub, that 400 watts goes to two subs, each sub gets 200 watts, and thus only pushes half as far. but you have both subs doing half the work each, so you get NO benefit at all.

you double power AND double woofers, now you have twice the duty of a single woofer, twice teh excursion, twice the air displaced. thus, a 3 dB increase.






that is not the issue. you say twice the power and TWO additional woofers was 9 dB. does that mean one additional driver (4 total) would be another 3 db increase? and then another? and another? each woofer adds 3 dB?

you say that double cone area same power is double spl. so you have 1 watt and one woofer. , thats 90 dB. add another woofer, thats 93 dB. add two more, (double cone area) thats 96 dB. add 4 more, total 8, thats 99 dB.

you are saying that if 1 watt and one sub is 90 dB, 1 watt and 8 subs will be 99 dB? I dont think so, you are not moving 8 times the air.




Finally, i will speak abotu teh 15. a 15 lets say has same excursion and exactly double the cone area of a 10. (not so far off) therefore, going from a single 10 to a single 15 is like going to two tens, and if it gets the same excursion from 1 watt as the 10, then you will get a 3 dB increase from just switching to the 15, becasue its moving just as far, but has twice the cone area. thats twice the pressure.

these are simple laws of physics here, you cant double teh work load and expect a fourfold increase in pressure.

 
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so basically i await my explanation still abotu how double power double aea = 6 dB increase.

 
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the 9DB reference was a mistake on my part..I said that [IMG]i/expressions/face-icon-small-smile.gif[/IMG] I did mean 6.

going from 2 to 3 woofers is a 1.5DB increases as it is not a doubling of cone area.. going from 2-4 woofers would be doubling..I'm tired..but that's beside the point...

 
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wanna throw $20 on it [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

 
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i think you need to reread yoru own post, but since you kinda corrected what you said, i think we are on teh same wavelength, because you cant double teh por and triple the woofers and get a 9 dB increase, which was the final option on yoru chart, which had nothing to do with only doubling woofers as you said you corrected yoruself on earlier....

im gonna wait till war and geo can explain exactly how it works. tried searching the audio forums, cant find any of the classic posts arguing how it works exactly. becasue i knwo that will support the laws of physics here.....

 
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Krisa..I forget her sername on SD has I believe 6 RF 18" Subs and 400 watts of power in her dodge dart and hits well over 150DB's...not sure if yer familiar with that one?

 
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nope, and im still waiting for those said to come online.....

 
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Cool.

 
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spoke with geolemon, he explained everything very clearly, would you like to guess who is right? (hint, it is who is usually right at the end of our debates...)

i still wanna digest the info a bit better before i post it.

(post *****! post *****!)[IMG]i/expressions/laugh2.gif[/IMG]

 
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I'd say 80% of our debates end up with both of us right and both of us wrong..and both us walking away knowing more info..

15% End up with you right..5% Me right..

But that's another persons opinions..ask Richard CLark..or a respected "expert" [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

 
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haha your good! we are both right, again! im baking right now, so cant write it up. but it had to do with us using two different scales [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

 
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It goes on lol..

Termpro thread

 
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alright, to avoid confusion between teh differences between acustic energy and pressure, i will refer as any change to the system as a change in OUTPUT. to define output, we will say that it is literally the amount a sub can displace through cone movement.

we start with teh test system, a single 10" woofer on 100 watts, that throws 1/4" due to those 100 watts.

We will also assume that 1/4" is not even halfway to xmax, and that efficiency is 100% (no power lost to heat, etc....)

so: excursion and power ARE on a linear scale, but a 2 to 1 ratio. therefore, you have to QUADRUPLE your power to double your excursion, therefore doubling output. Therefore, do double the output of our test system with a single 10, we would need to give it 400 watts.

this ALSO means, that if we halve power, we do not halve excursion! it only reduced to 75% of its original value. SO: if we add another 10 inch woofer, but give the PAIR 100 watts, we are increasing the output by 1.5, because each woofer is getting only half the power and moving three quarters as much.

to have a two woofer system have the same output as the one woofer system, we woul dneed to give each of the two woofers 1/4th the power (25 watts each, or 50 total) to equal the output of the single 10 on 100 watts.

now to teh system in question: when we double the power AND double the number of woofers, we exactly double the output. each woofer is pushing out what one would if it had 100 watts to it, and with double the cone area, you double the output.

makes sense? just like i was saying before, exept i had the ratio wrong, its not 1 to 1, its 2 to 1.

so how does this relate to pressure and acustic energy?

acoustic energy and pressure both are logarithmic scales, measured in dB, but a doubling of acoustic energy is equal to 3 dB, while doubling pressure (measured on any SPL meter) is 6 dB.

so is doubling your output (by doubling both woofers and power) increase your output by 3 dB or 6 dB? depends on what scale you use! those measuring by output will generally use the acustic energy scale, and competitors who care about numbers will use the pressure scale.

so we were both right =p and we'll always hear it both ways [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

 
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depends on the scale.. another one that pops into the 80% Bracket..

 
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we're just two different schools [IMG]i/expressions/laugh2.gif[/IMG]

 
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yup..the more we argue though..the more we learn

 
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Thanks for duking it out guys I learnt a lot [IMG]i/expressions/face-icon-small-smile.gif[/IMG] and i'm not being sarcastic. You guys sould playfight more often.

 
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lol, someones gotta lock these after 5 consecutive messages of mohawk and rabbit ....lol
[IMG]i/expressions/face-icon-small-cool.gif[/IMG]

that was entertaining and informative though [IMG]i/expressions/face-icon-small-smile.gif[/IMG]

RF Bwoy

 
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hehehe I agreee sooo good i love these guys