Options Available are as follows:
P Chamfer: This is a chamfer on the end of the pole, it helps to bring the air down around inside of the motor and helps cool the coil better. It also helps relieve the pressure underneath the dustcap. We recommend at the bare minimum to get this option if you choose this series of woofers.
Cooling: Self explanatory, the cooling channels are machined into the inside of the sub to help cool the coil FAR better. But there are some things that you sacrifice. There is less metal inside of the motor so it is a little weaker. If you are looking for a fart/burp only scenario for SPL we suggest that you do NOT get this option. Stick with only the P chamfer. Now if you are looking for a daily sub to beat on and you have 2000+ watts the BTL series is for you.
3rd magnet: This simply adds more clearance in use for the HiXmCoil. If you intend on using the sub for an SPL application we suggest that you get the 3rd slug with No cooling options and only the pole chamfer.
Flatwind: The flatwire coil option is standard in the BTL.
HiXmCoil: This coil is simply much longer than the normal dual 1ohm or dual 2ohm flatwire coils and allows for more xmax. If you are using this in a daily scenario we suggest that you choose this option, especially in the 15 and 18 inch models.
Daily or SPL: Simply put, if you plan on listening to any type of music you MUST choose the daily option. If it is strictly for a fart/burp scenario then choose the SPL option. The reason we have these options is the gap tolerances between the two are different. The gap in the SPL woofer is much tighter and FAR less forgiving in comparison to the Daily option. The Daily option simply gives the coil more wiggle room inside of the gap to deal with the non-linearity tendancys that you can get into when you are using a sub in a daily driving scenario. Typically SPL applications deal with 1 note and it does not change, therefore we can make the gap much tighter and get all of the motor strength that we can out of it.
Universal: This option gives you the choice to later chance the impedence of your voice coils. You can change from dual 2’s to dual 1’s and vice versa by reconing them. If you do not choose this option your motor(s) will be optimized per the coil resistance that you have chosen. (Dual 2’s will forever be a dual 2 motor, Dual 1 will forever be a Dual 1 motor).
