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<blockquote data-quote="John_E_Janowitz" data-source="post: 6137999" data-attributes="member: 550657"><p>Apparently since you have the desire to post your response in every thread I should post my response everywhere. I'm hoping that just maybe one of these times you'll take enough time to actually read and try to comprehend what is going on here. I think just about everyone else can understand. The 10 people who were here from the forum on saturday heard the already damaged papermaker woofer STILL playing to 200hz. No lack of upper end response. And that was with a small 125W/channel amplifier. You can see the videos here as well as all the people here to witness.</p><p></p><p><a href="http:////forum/showthread.php?t=418231" target="_blank">http://www.caraudio.com/forum/showthread.php?t=418231</a></p><p></p><p>Thanks to Bumpin Buick for the videos.</p><p></p><p>Again I'll try to educate you, although I'm starting to feel like i'm talking to a rock. If you have no upper end response it is due to your setup, not the woofer. I spent some time measuring transfer functions in Bose301's Jimmy, my Audi S4, and my bravada. One of the things you will find out is that positioning has a HUGE effect on upper bass response. You have a time delay from the direct signal off the woofer and the reflected signal off the back of the vehicle. This delay causes a substantial notch in frequency. Below are the measurements in Bose301's Jimmy.</p><p></p><p><img src="http://www.aespeakers.com/pics/measurements/vehicle_TF/2001_GMC_Jimmy_positioning.PNG" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>You can see that the red curve is smoothest and has the least amount of drop in the upper region. This is because the distance from the woofer to back of the vehicle is only a few inches. Any dip occurs well above 200hz and is not an issue. The closer the box is to the back of the vehicle, the better the upper response will be. If you have your box firing forward right behind the back seat this maximizes the time difference and you get the most significant dip at the lowest point in frequency. This is seen in the orange curve. The difference at 88hz between the 2 positions is 20dB. Output is lost everywhere from 57hz on up to over 100hz. Bose301's now stated he has much better upper end response from the same woofer just due to positioning. This of course makes perfect sense to most people.</p><p></p><p>As another example, here are the measurements from the 01 Audi S4. Again we see the same thing. Box at the back of the vehicle firing towards the back of the trunk gives the best results. Box firing forward at the back of the seat again is very poor. Box firing up actually causes even more loss lower in frequency.</p><p></p><p><img src="http://www.aespeakers.com/pics/measurements/vehicle_TF/2001_audi_s4_positioning.PNG" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>In case this isn't becoming clear yet, here is one more set of measurements from the 02 Olds Bravada. Again from 65hz on up, there is much more upper bass with the box at the back firing back. This vehicle, which i drive all the time has another cancellation that I have to deal with. The dip at 65hz occurs only at the headrest position and is changed due to mic placement. It just so happens my head has to go in that spot where the dip is.</p><p></p><p><img src="http://www.aespeakers.com/pics/measurements/vehicle_TF/2002_olds_bravada_positioning.PNG" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>What we can see here is that over and over, you lose upper bass output due to positioning. The current measurements were with the subwoofer only from 10hz to 200hz. No front stage was brought in. The other thing that affects the upper bass response is the integration with the front stage. That will be a lesson for another time though.</p><p></p><p>John</p></blockquote><p></p>
[QUOTE="John_E_Janowitz, post: 6137999, member: 550657"] Apparently since you have the desire to post your response in every thread I should post my response everywhere. I'm hoping that just maybe one of these times you'll take enough time to actually read and try to comprehend what is going on here. I think just about everyone else can understand. The 10 people who were here from the forum on saturday heard the already damaged papermaker woofer STILL playing to 200hz. No lack of upper end response. And that was with a small 125W/channel amplifier. You can see the videos here as well as all the people here to witness. [URL="http:////forum/showthread.php?t=418231"]http://www.caraudio.com/forum/showthread.php?t=418231[/URL] Thanks to Bumpin Buick for the videos. Again I'll try to educate you, although I'm starting to feel like i'm talking to a rock. If you have no upper end response it is due to your setup, not the woofer. I spent some time measuring transfer functions in Bose301's Jimmy, my Audi S4, and my bravada. One of the things you will find out is that positioning has a HUGE effect on upper bass response. You have a time delay from the direct signal off the woofer and the reflected signal off the back of the vehicle. This delay causes a substantial notch in frequency. Below are the measurements in Bose301's Jimmy. [IMG]http://www.aespeakers.com/pics/measurements/vehicle_TF/2001_GMC_Jimmy_positioning.PNG[/IMG] You can see that the red curve is smoothest and has the least amount of drop in the upper region. This is because the distance from the woofer to back of the vehicle is only a few inches. Any dip occurs well above 200hz and is not an issue. The closer the box is to the back of the vehicle, the better the upper response will be. If you have your box firing forward right behind the back seat this maximizes the time difference and you get the most significant dip at the lowest point in frequency. This is seen in the orange curve. The difference at 88hz between the 2 positions is 20dB. Output is lost everywhere from 57hz on up to over 100hz. Bose301's now stated he has much better upper end response from the same woofer just due to positioning. This of course makes perfect sense to most people. As another example, here are the measurements from the 01 Audi S4. Again we see the same thing. Box at the back of the vehicle firing towards the back of the trunk gives the best results. Box firing forward at the back of the seat again is very poor. Box firing up actually causes even more loss lower in frequency. [IMG]http://www.aespeakers.com/pics/measurements/vehicle_TF/2001_audi_s4_positioning.PNG[/IMG] In case this isn't becoming clear yet, here is one more set of measurements from the 02 Olds Bravada. Again from 65hz on up, there is much more upper bass with the box at the back firing back. This vehicle, which i drive all the time has another cancellation that I have to deal with. The dip at 65hz occurs only at the headrest position and is changed due to mic placement. It just so happens my head has to go in that spot where the dip is. [IMG]http://www.aespeakers.com/pics/measurements/vehicle_TF/2002_olds_bravada_positioning.PNG[/IMG] What we can see here is that over and over, you lose upper bass output due to positioning. The current measurements were with the subwoofer only from 10hz to 200hz. No front stage was brought in. The other thing that affects the upper bass response is the integration with the front stage. That will be a lesson for another time though. John [/QUOTE]
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