2x12" full range build


I'm about to build a box for two fane 12-250tc that looks like the first picture (150l, 40hz), but something bothers me. By putting all my box characteristics in a software like winISD or speakerBoxLite and looking at the cone displacement graph (second picture) it goes terrifyingly high.
I first thought that these drivers just can't handle such a big box but then I found this guy's build (link) with even more volume (90l. per driver).
Then I looked at fane's recommendation and they recommend a max of 75l. per driver but even with these numbers in simulator cone displacement gets crazy.

May it be that fane gives an xmax that correspond to absolutely 0 distortion (which I don't really care, it's for partys) and xmech is way higher ?
Or they expect us to not send full power with big boxes ?

Some help or ideas would be very appreciated :)



Don't know about nowadays, but historically Xmax use to be ~10% distortion and let folks find their tolerance while for prosound up to Xmech, but they typically use some form of high pass filter to protect them along with tuning around 1.56x Fs for basic protection.

Anyway, Hornresp (HR) dual driver 150 L/40 Hz Fb w/531 cm^2 x 45.19 cm vent sims ~35 Hz - up/Xmax = 150 W/> ~ 115 dB/m and guessing 5 mm max = 250 W/> ~ 118 dB/m. Add in some Le distortion and GD jumps from ~24 ms to 31 sec..
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This is a common scenario and there is going to be some disparity between what the plot looks like, and the reality of it.

(By the way, if you want this thread moved to 'Subwoofers' let me know since this question may be a good fit there.)


Joined 2003
Just for 'giggles', did a pioneer's prosound alignment = 108.3 L/78 Hz/5 mm = 500 W from ~70 Hz - up and 2 kW dynamic headroom from 150 Hz - up for a nominally flat 130 dB/m/2pi/80 Hz - up. Add a commensurately powerful sub and do some serious partying! ;)
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I will list several possible scenarios:
1. You don't play music loudly and the xmax limit will not be an issue.
2. You don't play music with deep bass below 40 hertz and the xmax limit will not be an issue.
3. You do play music loudly with deep bass and will benefit from an electronic high pass filter.
4. You do play music loudly with deep bass and will benefit from a smaller enclosure, possibly sealed.
5. You do play music loudly with deep bass but don't hit the woofers Xmech and actually enjoy the additional bass distortion.
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If you want to use it real fullrange (with bass) don't count on more than 25 watt per driver. Above the bass is not usable because of the limited xmax (and xmech). I use it that way and it's a great garden speaker. But my cabinet is a lot bigger (175L) than yours for a low tuning.

If you use it with a woofer taking care of all below 250-300Hz, you can use advertised power, and use it as it's intended to be used by the manufacturer. I've seen it used in drum monitors for live concerts that way, with a Fane 18XB as woofer.
3. You do play music loudly with deep bass and will benefit from an electronic high pass filter.
This. Ported boxes should always have a high pass filter - In your case, second order around 40Hz should do it.
Your amplifier will already have a high pass filter on its input as the DC blocking capacitor, and simply changing this to a lower value may be enough
In WinISD, there is a filter option where you can play around with different values to see the results

Thank you!
Considering all of your answers, I think I will use it as a full range driver at low volume and later buy a mini DSP (or similar) to high-pass around 35 and a better amp to benefit full volume. It will be like a 2 in 1: full range for alone myself and a 40hz-.. powerful party speaker :)

I won't use a separate sub because it's an upgrade of my first 2x12" that became "the box that we carry anywhere and throw party simply" so it needs to be one full range piece.

Just to be sure, I will hear the distortion early enough to not damage the drivers when I don't have a high-pass ??
You will hear the voices garble quickly without crossing over to a woofer or subwoofer say 100hz.

I'm not sure if combing will be a problem at 12', but definitely eq down the 1.5khz - 3khz hump that is present 30 degrees off axis.

I look forward to your opinions and results !!!!