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<blockquote data-quote="Immacomputer" data-source="post: 8288524" data-attributes="member: 570419">A standard line will have slightly lowered mechanical power handling for starters. It will also have slightly less output. Depending on the size, sometimes the compression chamber is really just part of the tline that&#039;s slightly larger making it a minutely tapered line lol. This gives minimal differences. If large enough though, it can add a Helmholtz resonance to your transmission line (ported box style). If done correctly, this can gain you increased mechanical handling and output around the combined 1/4 wave resonance and the Helmholtz resonance. If you&#039;re able to make these two values equal, interesting things can happen. For instance, I made a tline like this for an old Acoustic Elegance AV12 that matched the Fc for the sub in a sealed box of equivalent size, the Helmholtz resonance, and the 1/4 wave resonance. It took some work to get all three to equal and they all were 35hz. In my old integra hatch, it was -3dB at 17hz and 75hz with a peak at 22hz of 3dB. At 22hz, the sub wouldn&#039;t move just as if it were in a ported box tuned to 22hz but it wasn&#039;t. It was also flat within .1dB everywhere except at the end of range and at 22hz. It was also loud enough to do a small hair trick at 22hz with just the sunroof open (I guess that&#039;s kind of cheating... Still loud as **** for that low and that flat.). The compression chamber allowed me to get those three resonances to line up. Combining them gave a nice smooth response with plenty of output capabilities and not a huge enclosure though it was probably 3.5ft^3 for one 12 lol.Size calculations for the compression chamber are based around VA&#039;s and (bl^2)/re. The bigger the compression chamber, the more boomy the response will be. The smaller, the tighter and controlled the response will be. It also varies based on your line.</blockquote>

[QUOTE="Immacomputer, post: 8288524, member: 570419"] A standard line will have slightly lowered mechanical power handling for starters. It will also have slightly less output. Depending on the size, sometimes the compression chamber is really just part of the tline that's slightly larger making it a minutely tapered line lol. This gives minimal differences. If large enough though, it can add a Helmholtz resonance to your transmission line (ported box style). If done correctly, this can gain you increased mechanical handling and output around the combined 1/4 wave resonance and the Helmholtz resonance. If you're able to make these two values equal, interesting things can happen. For instance, I made a tline like this for an old Acoustic Elegance AV12 that matched the Fc for the sub in a sealed box of equivalent size, the Helmholtz resonance, and the 1/4 wave resonance. It took some work to get all three to equal and they all were 35hz. In my old integra hatch, it was -3dB at 17hz and 75hz with a peak at 22hz of 3dB. At 22hz, the sub wouldn't move just as if it were in a ported box tuned to 22hz but it wasn't. It was also flat within .1dB everywhere except at the end of range and at 22hz. It was also loud enough to do a small hair trick at 22hz with just the sunroof open (I guess that's kind of cheating... Still loud as **** for that low and that flat.). The compression chamber allowed me to get those three resonances to line up. Combining them gave a nice smooth response with plenty of output capabilities and not a huge enclosure though it was probably 3.5ft^3 for one 12 lol. Size calculations for the compression chamber are based around VA's and (bl^2)/re. The bigger the compression chamber, the more boomy the response will be. The smaller, the tighter and controlled the response will be. It also varies based on your line. [/QUOTE]

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