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<blockquote data-quote="helotaxi" data-source="post: 2444487" data-attributes="member: 550915">Few other things...Anechoic F3 has no real bearing on actual in car response.&nbsp; A sealed box can pretty well play flat well into the infrabass region regardless of the sub in it thanks to cabin gain.There are also several subs (very popular ones on this forum at that) that have F3s in the neighborhood of 80hz in a Chebysev or Butterworth ported alignment.&nbsp; The Fs of said subs are in the low 20&#039;s, but without the right Qts, the Fs has no bearing on the F3, which has no bearing on incar response.&nbsp; Anyone with real experience in car audio will know that a sealed box with an anechoic F3 of 60Hz will play lower than you can hear.&nbsp; Whether or not the sub really rattles your guts at that freq is going to depend on how much air the subs are moving.&nbsp; It&#039;s going to take about 4 8s to move as much air as a single 12 and play as loud.The whole stereotype of bigger subs playing lower is based entirely on volume at low frequency not flat frequency response at low frequencies.&nbsp; Bigger drivers are louder.&nbsp; Not just at low freqs but across the entire range that they play.&nbsp; Because of that simple fact it would logically mean that they are louder at low freqs, too.Fs is dependant on two things: Vas and Mms.&nbsp; It is inversely proportional to the two.&nbsp; An increase in one without a proportional reduction in the other will lower the Fs.&nbsp; Since an increase in cone diameter will result in an an exponential increase in Mms.&nbsp; Duh.&nbsp; Increase Mms without stiffening the suspension comensurately and you get a lower Fs.&nbsp; Stiffening the suspenion and/or increasing the Mms will also lower the efficiency of the driver.I can think of a couple of series of drivers that have the same motors and generally same suspensions throughout the model line.&nbsp; In every case the larger driver has a lower Fs (and also needs a MUCH bigger box).&nbsp; In every case, that higher Fs did not keep the smaller driver from playing well into into inaudibility on the low end.&nbsp; It just didn&#039;t play as loud as it bigger brothers.Basically , you&#039;re both right.&nbsp; The larger drivers have a lowr Fs and Fs isn&#039;t the end all be all of determining low freq response.&nbsp; That&#039;s the long and the short of the whole thing.</blockquote>

[QUOTE="helotaxi, post: 2444487, member: 550915"] Few other things... Anechoic F3 has no real bearing on actual in car response. A sealed box can pretty well play flat well into the infrabass region regardless of the sub in it thanks to cabin gain. There are also several subs (very popular ones on this forum at that) that have F3s in the neighborhood of 80hz in a Chebysev or Butterworth ported alignment. The Fs of said subs are in the low 20's, but without the right Qts, the Fs has no bearing on the F3, which has no bearing on incar response. Anyone with real experience in car audio will know that a sealed box with an anechoic F3 of 60Hz will play lower than you can hear. Whether or not the sub really rattles your guts at that freq is going to depend on how much air the subs are moving. It's going to take about 4 8s to move as much air as a single 12 and play as loud. The whole stereotype of bigger subs playing lower is based entirely on volume at low frequency not flat frequency response at low frequencies. Bigger drivers are louder. Not just at low freqs but across the entire range that they play. Because of that simple fact it would logically mean that they are louder at low freqs, too. Fs is dependant on two things: Vas and Mms. It is inversely proportional to the two. An increase in one without a proportional reduction in the other will lower the Fs. Since an increase in cone diameter will result in an an exponential increase in Mms. Duh. Increase Mms without stiffening the suspension comensurately and you get a lower Fs. Stiffening the suspenion and/or increasing the Mms will also lower the efficiency of the driver. I can think of a couple of series of drivers that have the same motors and generally same suspensions throughout the model line. In every case the larger driver has a lower Fs (and also needs a MUCH bigger box). In every case, that higher Fs did not keep the smaller driver from playing well into into inaudibility on the low end. It just didn't play as loud as it bigger brothers. Basically , you're both right. The larger drivers have a lowr Fs and Fs isn't the end all be all of determining low freq response. That's the long and the short of the whole thing. [/QUOTE]

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