Excursion vs. Cone area

[JonJT 10+ year member]

As we all know, total driver displacement influences the drivers ability to play low. Now, there are 2 ways to get there, mechanical movement and cone area. We also know that increased movement can induce extra distortion via ineffective surrounds, BL reduction, mechanical compression, etc. Increasing cone area calls for increased moving mass, which calls for a stiffer surround.

I would just like to hear someone in the know to contrast the 2 characteristics in relation to total displacement, and sound quality and, if possible, suggest which would be preferable.

Ex, we all know and love the high excursion woofers that Adire, RE, etc has created. We've got drivers like te Koda 8, Extreme excursion for an 8 inch woofer, but a small cone area. Would this driver be better off with a larger cone and less excursion from a low frequency extension and sound quality perspective?

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[Spkrman]

Larger woofer, doesnt have to work as hard to put out the same displacement... you can also generally save $ by going with a larger, lower xmax woofer.

Of course, its all install //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[JonJT 10+ year member]

Yeah, I know, but I was speaking from a strictly technical standpoint.

 

[Spkrman]

theoretically it doesnt matter... displacement is displament. Your moving the same amount of air either way.

 

[T3mpest 10+ year member]

I'd say cone area wins this battle overall. It takes power to increase excursion, in many cases a lot of it. 4x any given amount of power to raise by 3db or in other words, double excursion. Cone area is inherent. If we have a 15 inch sub running off 1000 watts we would be better off getting 2 15's and giving each of them 500 watts. We'd 1/2 power, which wouldn't lose half of our excursion, but then we'd gain 3db by the increases surface area.

 

[nauc 10+ year member]

isnt 2x the power = to a 3db gain

 

[req 5,000+ posts]

isnt 2x the power = to a 3db gain

roughly, thats what i was thinking... not 4x...

 

[Mackenzie 10+ year member]

roughly, thats what i was thinking... not 4x...

x2 around that area

 

[vosschs 5,000+ posts]

**scrolls down to see what jmac has to see** clicks back cuz i dont know wtf he is talking about

 

[vosschs 5,000+ posts]

Sub A produces 110 dB w/ 10 mm of excursion (250 watts) ... Assuming it can handle 1000 watts and 20 mm of excursion with any undue effects (power compression, etc.) ...
Doubling Power ...

dB = 20*Log(D1/D2)

dB = 20*Log(Sqrt(2)*10*Sd/(10*Sd))

dB = 20*Log(Sqrt(2))

dB = +3.0103 dB

110 + 3.0103 = 113.0103 dB

Doubling Displacement (4x Power)

dB = 20*Log(2*10*Sd/(10*Sd))

dB = 20*Log(2)

dB = +6.0206 dB

110 + 6.0206 = 116.0206 dB

OK MUCH BETTER THANKS!//content.invisioncic.com/y282845/emoticons/veryhappy.gif.fec4fed33b4a1279cf10bdd45a039dae.gif