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Your Price:
$354.00 (You save $61.00)
70.00 LBS
Estimated build time of 10-15 business days
Calculated at checkout

Product Description

All US steel machined in house at Fi.

The BL Series fills the gap between the all out SPL monster and a solid daily driver. Featuring a chamfered solid pole piece and standard double stack motor structure with 8.660" magnets as the foundation for a truly tough subwoofer, you can choose from a variety of options to custom tailor the sub for your exact application. With the addition of the hyper chamfer, or our patent pending heli-cooling channels along with the Daily option, you can bump up the subs thermal capacity for long term daily driving abuse. Looking for an ultra tough SPL sub? Choose the SPL option, one of the 8 layer aluminum flatwind voicecoils, add power, and let it rip. With head cracking upper bass and brutal low end, the BL handles the extremes with ease.


BL Series: 10”, 12”, 15”, and 18”
Dual 1 and Dual 2 Ohm (custom options available)
Cast basket
Wrap around gasket
Kraft pulp fiber reinforced cone
Single layer wide foam surround
Push terminals
16 integrated leads option
FEA optimized motor
High Flux density design
3” diameter 4 layer coil (Flatwind option)
Double stack magnets
Five progressive spiders
Optional Heli-cool systerm
Machined in house at Fi
And many other custom options


Fs: 33.2 Hz | 33.2 Hz
Re: 0.7 Ohms/coil | 1.4 Ohms/coil
Qms: 5.82 | 5.82
Qes: .32 | .32
Qts: .30 | .30
Mms: 302g | 302g
Cms: 0.88mm/N | 0.88mm/N
Sd: 1210cm^2 | 1210cm^2
Vas: 181.0 l | 181.0 l
Spl: 94.1dB 1W/1m | 94.1dB 1W/1m
Bl: 16.6 N/A | 22.7 N/A
Xmax: 18mm | 18mm
Rms: 1500W * | 1500W *
Sealed box: N/A cuft | N/A cuft
Ported box: 5-8cuft | 5-8cuft
Sub OD: 18.500” | 18.500”
Cut ID: 16.750” | 16.750”
Mounting depth: 9.750” * | 9.750” *
Displacement: 0.26cuft * | 0.26cuft *


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Product Reviews

Showing reviews 1-10 of 24 | Next

  1. Hot damn 5 Star Review

    Posted by on 28th Jul 2015

    I have one of these behemoths in a 92 jeep Cherokee running off 1500 watts and it's amazing. I plan on buying a second one in the near future. Bass is strong and crisp, the woofer is heavy and feels very durable, FI is the way to go.

  2. Very loud! 5 Star Review

    Posted by on 28th May 2015

    I put two of these fully loaded in a ported box in my Tahoe! Very loud and moves a lot of air. Got them on a 3500 watt amp. I have always been a fan of FI. I do suggest getting fully loaded

  3. amazing performance & quality craftsmanship 4 Star Review

    Posted by on 28th Apr 2015

    Started off a lot smaller, different brands of course, spent a Some time with different brands of subs and different sizes, and I quickly learned the bigger the sub, the more power you pushed generally , and you were going to loose sound quality. I wanted to stay around 12" subs because of quality, then I heard the Fi Audio sub, it was a pair of bl series 18s on a crescendo amplifier custom built box, it was then at that moment very clear to me that I was using the wrong equipment, I now own 4 of the bl series 18's. Can't see running another sub, they are rated at a very moderate 1500 RMS, personally have had 4500s on two of them, they got un-clipped clean power, I beat on them for 8 months, literally GAVE THE ENTIRE 4500 watts to them, decided to go with 2 more, ordered re-cones so all Subs would be fresh, to my surprise they were no where close to needing a re-cone! The subs on that power in that box created enough pressure to known back hatch open on my Tahoe, but sound quality is surely there..Old setup was 2 Fi audio bl series 18's, Phoenix gold elite.1 series, 2 stinger spp1500's, 2 runs stinger pro series 1/0 gauge, custom 13 cu ft box built by victor bazan tuned to 30 hz I believe.

  4. Demm!! 5 Star Review

    Posted by on 9th Oct 2014

    As soon as the delivery man brought it I knew this was something serious. Then I opened it. Holly this thing is heavy and well made you can't push it down like most subs. I didn't hook em up yet but I'm in love already !!

  5. Beyond impressed. 5 Star Review

    Posted by on 8th Sep 2014

    Ok, I started off small when I bought my first system. Only 2 10s. From there I went bigger and bigger. One day I just decided that I wanted to go huge. Ordered two BL 18s and threw 2 Db 2800.1s at them. When I ordered them, I bought everything extra that you could buy. They are rated for 1500rms but at the moment I have 2k rms at 1 ohm stable on each subwoofer. The speakers are barely flexing and seem to not be bothered by it. Soon to be putting 3K on each subwoofer. I highly recommend.

  6. Amazing Subwoofer. Loud as hell! 5 Star Review

    Posted by on 14th Aug 2014

    This subwoofer is loud as F***. And for only 1500 rms that's crazy. I give mine around 2000 watts and it still can handle more power. This 18 is a lot louder than a lot of other systems too. I get nice windshield flex and a lot of air movement. People hear me coming from deep. The funny thing is the subwoofer shakes houses that I drive by, no joke! It also give a little bit of a hairtrick haha. It hits the high notes good and also smacks on the lows. It took a month to get my subwoofer but it was definitely worth the wait. I'll be ordering another one soon.

  7. Top of the line quality 5 Star Review

    Posted by on 26th Jul 2014

    Everybody that heard the name already knew this is top of the line quality and the performance speaks for itself. And the dimension for the box Fi Audio gave really helped as well.

  8. customer service 3 Star Review

    Posted by on 8th Jul 2014

    Customer service was terrible they messed up my order and I waited forever to get the product but the product itself is amazing and well built

  9. Good Strong Subwoofer-Not your average Subwoofer-Best 5 Star Review

    Posted by on 27th May 2014

    I had it for a few weeks not played much past half volume just so sub loosens up to be safe, box around 6.91 with 2 6" aero ports. Already starting to want to beat you up tuning is a little below 33Hz. I wondered how much lower it would of hit if had a little more Xmax, but so far it is a very impressive sub. I have it on a HiFonics Brz 2400 and Fi help me get the extra cooling, flat wound coil 2 ohm sub, Daily Universal option were used, it does not disappoint. One 18 seems hit harder then the 2 Kicker Comps I use to have in pickup port through, to me very accurate, I always figured you can turn bass down but if it is not there your out of luck, diffidently a sub above the rest. TY Fi for putting up with all my questions and their help.

  10. Fi stands for Fucking Insane 5 Star Review

    Posted by on 6th Mar 2014

    I recently purchased a BL18! I have always wanted a Fi subwoofer and finally got it. It was my first time ordering from them but it will definitely not be my last. It only took about 2 weeks to get my sub from the date I placed my order. Any questions I had I emailed and they got right back to me with the answer. This sub hits so fucking hard it's insane. Thank you Fi for making my car audio experience the best it's ever been!

Showing reviews 1-10 of 24 | Next