That line of drivers is not really optimized for any specific type of tuning i.e. sealed, ported, passive radiator, TL, etc... As such, it works equally well ( or is it equally poorly ??? ) in several different alignments. It was kind of designed as a "universal" driver and work in various alignments. Only problem is that it will do all of them kind of "half-heartedly" if you know what i mean.
Drivers with a very long throw tend to be very poor at doing any type of pitch and lack definition. Part of this is typically due to the increased amount of travel that the suspension requires and the associated lack of damping / increased ringing. The other part has to do with amplifier being able to control the driver and damping factor.
Woofers with large motor structures generate a measurable amount of reflected ( stray ) voltage back into the amp. A woofer with a BIG motor and a REAL long throw is capable of producing even more stray voltage that the amp has to deal with. The fact that these drivers are very low impedance somewhat compound these problems in multiple ways.
Since it is such a low impedance, the driver will be pulling quite hard on the amp as it is. This typically lowers sound quality on most amps, makes them run hotter and reduces the damping factor of the amp. You now have an amp that is working as hard as it can, running hotter than normal, has reduced damping factor and is now being hit with a much higher level of reflected emf ( electromotive force or "voltage" ) than it would normally see.
In order to overcome all of the above factors and keep control over the driver, it would need to be capable of extremely high power levels. I am talking both current and voltage here, not just one or the other. That is why i said a KW ( kilowatt i.e. 1000 watts ) for each voice coil.
Due to the problem with ringing, this type of driver typically works best crossed over VERY, VERY low. This keeps any of the mid or upper bass out of its operating range and minimizes the harmonic content that it will generate. If you don't do this, you'll typically experience muddy bass even though it is above the range that this driver is handling.
I will admit that this driver appears to have a pretty tight suspension with good impact, so ringing might not be quite as bad as i suspect. However, it is kind of a high Q design for porting and that is the part of the market that they seem to be pushing it for. High Q designs in ported enclosures typically ring like crazy, which is not a good thing. On the other hand, it does not appear that the driver would go as low as expected using "tight" sealed woofer alignments, making it kind of a "half breed" that isn't really at home anywhere. Something that comes to mind is a big brute that will never be capable of fully harnessing and optimizing the power that it is capable of. Sean
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