Ok let’s jump into 

Starting with the JL audio 12WO-4

This woofers cone  is made of polypropylene which gives you a warmer sound vs paper cone and the surround is foam Which is consist in the full JL audio line except in their shallow line 

It handles 300 watts rms 600 peak  which is the least among the group

• frequency response: 22-250 Hz with 22hz being the lowest frequency the woofers in this comparison can play. 
• sensitivity: 85.64 dB

And this woofer only comes in a single 4 ohm unlike all the other woofers we’ll be looking at that come in dual voice coil in either 2 or 4 ohm. Besides the memphis which comes in a selectable 2 or 4 ohms. So with this JL woofer you are limited when it comes to matching an amp especially if you only want to run a single sub. 

Reco sealed box is 1.375

And ported is 1.75 

The resonate freq is 28.43 now the resonate freq or FS is where the woofer natural resonates so in most cases lower is better if your looking for deep bass 

And the last thing we are gonna look at is xmax which is The measure of a speaker cone’s maximum excursion in one direction while maintaining a linear behavior. And for this woofer it is 11.4 mm

This woofers voice coil is measured at 2” 

Special feature included Dynamic Motor Analysis – DMA that JL has used in there woofer for years that address issues around speaker motor linearity. 

Elevated Frame Cooling

design delivers cool air through slots directly above the top-plate to the voice coil of the speaker. This not only enhances power handling, but also sound quality by minimizing dynamic parameter shifts and power compression.

Current retail price $199

Next the Rockford fosgate P2 12

The cone is Made of Kevlar® reinforced paper 

• Santoprene surround
• 400 watts RMS (800 watts peak power)
• frequency response: 27-250 Hz
• sensitivity: 86 dB
• Comes in either a dual 2 or 4 ohm 
• sealed box volume: 1.02cubic feet
• ported box volume: 1.79 cubic feet
• The resonate freq is 27.2
• Xmax is 10
• 2 1/4” voice coil 

Special features include 

An anodized aluminum voice coil former and spider venting help keep the subwoofer cool.

hybrid StampCast basket provides strength while minimizing weight 

Currently retail price $189

Moving on to the memphis PRX1224

• treated paper cone with double-stitched butyl rubber surround , full poly proprlen dust cap 
• power handling: 300 watts RMS (600 watts peak)
• frequency response: 30-150 Hz
• sensitivity: 85.8 dD
• selectable 2- or 4-ohm impedance( which we’ll talk about more in a minute)
• sealed box volume: 1.25 cubic feet
• ported box volume: 2.75 cubic feet

• Resonate freq is 35
• Xmax is 10.5

Now let’s go back to the selectable impedance, this woofer has a 2” US grade 220C copper voice coil. and actually has 3 voice coils enabling it to have true 2 or 4 select-ability impedance Now the reason why they use US grade 220c copper is because the Chinese or even Japanese 220c copper not as good or more tolerant than US copper. Now in order for memohis to achieve there selectable 2-4 ohm driver the these coils have to be precise and a better quality voice coil makes for a better more reliable driver. 

• Special feature include double stiched surround on the cone  also the dvvc. Direct vent voice cooling and also the treated paper cone with the full polypropylene dust cap giving you the best of both worlds with the stiffness of the treat paper along with the warm mess of thr polypropylene. 
• Current retail $179

Next kickers COmpr series 

• njection-molded polypropylene cone
• double-stitched Santoprene rubber surround
• power handling: 500 watts RMS (250 watts per coil) 
• peak power handling: 1000 watts
• frequency response: 25-500 Hz * this has the widest range 
• sensitivity: 86.9 dB this is the best out of the group* 
• Comes in either a dual 4 or 2 ohm 

• sealed box volume: 1.0 – 2.0 cu. ft.
• ported box volume: 1.75 – 2.25 cu. ft.
• FS 23.14 which is the lowest out of these 12s 
• Xmax 12.73   
• 1.95” copper voice coil now these last 3 specs are not listed on kickers website so we called them and this is the info they gave us. 
• Special features include Forced Air Cooling system, using the motor structure to pull air across the voice coils, helping the sub run up to 25% cooler than the previous model.

Next the alpine s-series 

• Kevlar reinforced pulp cone with HAMR Santoprene rubber surround
• power handling: 600 watts RMS (300 watts per coil)* these handle the most out of the bunch. 
• peak power: 1,800 watts but not recommended 
• frequency response: 24-200 Hz
• 86.4 dB at 1 watt 
• These come in either dual 2 or 4 ohm
• Ideal sealed box .85 cf
• Ideal ported 1.51 which is the smallest recommended  box  sizes for both sealed and ported out of the 6 
• Resonate freq is 31
• Xmax is 15 mm and that’s the largest of the bunch * just edging out the sundown which comes in at 14mm