Yes. If you are using the staggeringly expensive scan speak acoustic resisters, one for cabinets up to around 40 litres. 40-80+, two per cabinet.
Not an exact science. Start with drivers with a relatively high qts, certainly above .35 and decent excursion. The original Dynaudios used the 10" Seas drivers, long gone. Peerless sls 10 and 12 are good drivers for this application.
For measured results used Dats software which will give you the impedance curve, the qts and fs, etc. Adjust stuffing amount to tune to qts of around .7...
A simple "ported" to atmosphere gives you around a 15db/octave roll off and not the same power handling as the dual chambered aperiodic cabinet design but does have the "advantage" of utilising a small cabinet volume. To establish cabinet volume, design for a qts of around 1.2 assuming a sealed cabinet. Your qts will drop of course with the damped port.
The twin chambered aperiodic is a very good way of achieving superb bass performance but comes at the cost of a large cabinet. Always a good thing for bass!! You split the cabinet internally into two chambers. The smaller one is around 1/3rd the vas of the driver. The driver is loaded into this one, benefits include a non symmetrical small cabinet which is great for mid reproduction. The small cabinet is "ported" using the acoustic resister into the larger chamber which is between .75 and 1 x the driver vas.
Loading this way gives you the 12 db/oct roll off of a sealed cabinet and an f3 approaching the fs of the driver. Superb, damped, great power handling, optimised mid range cabinet, low group delay associated with sealed box.
But a big box....
Many thanks for this information, I will probably use 1/3 vas - 1x vas for my next one ( the 1x becoming 2x and shared between two drivers, Dayton audio TCP115-8 4" ), have you found any similar information on the size of the acoustic resistor, I think Hi Fi world published something on slots but like a total idiot I didn't buy that issue, something I now regret!
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