Dual skar12 paraflex C CRAM

140dB at 30hz requires 4 big enclosures outside or 1 big enclosure in a corner or vehicle.
You stated 200-220 liters maximum.
Yeah, at the time i wasn't aware of how subs behave...
now i have a better picture of how size, SPL and extension interact....

and i know that you dont get along with 750+ bux drivers but
like to get the most bang for the buck :)
T/S theory peters out at the driver's effective upper [Fhm], lower [Flc] mass corners, so any bandwidth response plot beyond these points are strictly due to [inputted] inductance [mH] and/or mass roll off, with on-line freeware generally just flatlining it:

Fhm = 2*Fs/Qts' end of acceleration BW

Flc = Fs*Qts'/2 end of roll off BW [normally never used]

Qts' = 2*Fs/Fhm

Maybe more easily understood from a horn loading POV along with all the extra math, pg. 7.
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Almost there! I added 15.24cm (6") to both L23 and L34.
Next, I'm going to try removing the stepped function with a 335.48cm2 throat and 2,683.87cm2 mouth.
Basically, I need to get to 130dB at 30hz in 2pi to get to 140dB at 30hz in 0.5pi or 4 enclosures.









I can’t get anymore outa these (im 🐔) having smelt the voice coils on these a few times (😝Oopsie daisy 😝) I’m too scared to push them any further 😃

the ’roar’ i built with these is tuned to 28.8, but I think it pushes too far and don’t feel safe recommending it

but maybe the 36 hz single paraflex I have with this driver, but it’s got that misaligned resonator issue in the response that is ‘weirdAF in ‘ para flex‘es(it always has more resonance/cancel going on then horn response shows left over from the other sides 3/4 mode because nobody sims them or builds them ‘right’, including me in this case)


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I like how you attack that excessive ‘ 3/4 resonance’ with the LP filter. It works really good for me in ‘reality’ (I have 3:1 resonators in parallel) as does a rectangular waveguide @ exit


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Guys you rock!!!
You are not going to believe this but....
Boss was off today so ... I was simming for 4 hours... Almost all of Lord Sansui plans with freeCad...and HR....and always crash with a wall of xmax.... at 700...600..800 watts...

So I guess your fruits of your labor will be!!
Try mid 30s and be happy you did . i just got hit up by another guy who smoked these @~29 hz tuning in a BR.
the sim can give you ‘hints’ of what you must assume is a red flag/warning or foreshadowing if you pay atention to more than ‘SPL’ blinders.

30 hz us an all but guaremanteed failure and/or compromised longevity . Look at the TS parameters ? 38.5 Fs and with a 0.35-0.4 Qts to argue it.
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