Fi Car Audio MT Series Subwoofer
£889.00
- EUR: €1,019
The new MT Series of subwoofers is our competition, high linearity extreme power handling driver
SUCCESSOR to the TEAMv3 Series!
The 2025 MT Series of Fi subwoofers is designed to meet the needs of the serious competitor and and monster basshead. With a massive 4″ voicecoil for increase thermal capacity, we designed the rest of the motor via FEA to optimize the proprietary US steel (water jet and machined in house at Fi when your order is placed). Using three ultra-high grade Y35 magnets, a flux flow derived back plate geometry, and a solid pole with aluminum sleeve and aluminum compression cap, there is plenty of thermal capacity in the MT Series. Our Fi designed heavy 5 spider pack coupled with our special 144 tinsel count leadwire to keep the moving assembly under control at extreme excursion levels. The reworked surround geometry on the 12″, 15″, and 18″ models optimizes cone area vs excursion yielding the most output vs excursion. The 2022 MT Series is designed for competition use and monster daily driving systems requiring high linearity and extreme power handling. From a punishing low end to the subtle nuances in your favorite reference track, the MT Series delivers!
The MT Series allows for 2 stages of cooling and inductance mitigation.
STAGE 1: Is a machined aluminum pole sleeve that reduces inward coil inductance shift and helps linearize overall inward vs outward inductance reducing distortion. This sleeve also aids in heat wicking to the pole as aluminum has a significantly better thermal coefficient than steel alone does.
STAGE 2: Uses both the pole sleeve and an aluminum pole cap to increase compression and cooling. Also, via its profile and increased aluminum around the coil as it gets closer to the pole itself, inductance is further reduced. As a coil moves inward its inductance increases relative to the steel it surrounds, so the closer the coil is to steel, the more aluminum you would want in proximity to it. As inductance is the natural resistance to directional change, reducing and linearizing it increases output range and can ease some amplifiers operation.
Features
Dual 1 and Dual 2 Ohm
Extra heavy aluminum basket
Wrap around gasket
Kraft pulp fiber reinforced cone
Dual layer wide foam surround
Standard heavy duty stitched Push or Hybrid terminals
144 tinsel count leads
FEA optimized motor design
Ultra Flux density design
4” diameter 4 layer coil
Triple stack magnets
Carbon cap standard
Stage 2 Aluminum Cooling
Water jet and machined in house from US steel
Five extreme 10″ spiders
6″ Gloss Carbon dustcap
Thiele-Small Parameters
| MT 12 | MT 15 | MT 18 | |
|---|---|---|---|
| Coils | DUAL 1 | DUAL 2 | DUAL 1 | DUAL 2 | DUAL 1 | DUAL 2 |
| FS | 34.3 Hz | 34.3 Hz | 32.2 Hz | 32.6 Hz | 31.7 Hz | 32.1 Hz |
| RE | 0.75 | 1.49 | 0.75 | 1.49 | 0.75 | 1.49 |
| QMS | 7.93 | 7.83 | 8.52 | 8.43 | 9.91 | 9.79 |
| QES | 0.36 | 0.38 | 0.38 | 0.40 | 0.45 | 0.47 |
| QTS | 0.35 | 0.37 | 0.37 | 0.38 | 0.43 | 0.45 |
| MMS | 408g | 404g | 444g | 435g | 516g | 503g |
| CMS | 0.53 | 0.53 | 0.53 | 0.53 | 0.68 | 0.68 |
| SD | 480cm^2 | 480cm^2 | 810cm^2 | 810cm^2 | 1210cm^2 | 1210cm^2 |
| VAS | 17.17 l | 17.17 l | 49.0 l | 49.0 l | 95.4 l | 95.4 l |
| SPL | 84.6dB | 84.4dB | 88.1dB | 88.1dB | 90.2dB | 90.1dB |
| BL | 19 N/A | 26.1 N/A | 19 N/A | 26.1 N/A | 19 N/A | 26.1 N/A |
| XMAX | 33mm (One Way) | 33mm (One Way) | 33mm (One Way) |
| RMS | 4500W | 4500W | 4500W |
Technical Specifications
| MT 12 | MT 15 | MT 18 | |
|---|---|---|---|
| Overall Diameter | 12.500” | 15.625” | 18.500” |
| Cutout Diameter | 11.125” | 14.125” | 16.750” |
| Mounting Depth | 10.00” | 11.00” | 12.250” |
| Driver Displacement | 0.19cuft | 0.21cuft | 0.26cuft |
| Ported Box | 1.8-2.5 cuft | 3-5 cuft | 5-8 cuft |
This is a complete list of options; not all options are available on all models.
See drop down selections for options available with each speaker model.
Cooling Stage: The new cooling stages are aluminum rings or plugs that aid in cooling and reducing the inductance of a coil (as well as linearizing it to further reduce distortion). The first stage is a machined aluminum sleeve over the pole. This has better thermal conductivity than steel alone does and reduces the effect of the coils inductance increase being an iron core inductor. The second stage includes the first pole sleeve and adds an aluminum pole cap that increases compression and cooling. The third is the first two stages along with the large visible heatsink that surrounds the outside of the coil and transfers heat to the ambient environment as well as greatly reducing the inward inductance of the coil. The overall effect increases cooling/thermal capacity as well as linearizing in vs outward inductance shift reducing distortion ad increasing bandwidth
Cooling: Self explanatory, the cooling channels are machined into the inside of the sub to help cool the coil FAR better. This option is available for subs that do not have staged cooling. While it is not a visible option, it makes a huge difference in long term thermal capacity.
High QTS: This option is for users who intend on using the subwoofer in only a sealed enclosure.
Low QTS: This option is for users who intend on using the subwoofer in only ported enclosures.
Extra Spider: This option adds an additional spider to the spider pack to help with mechanical power handling and keeping the moving assembly under control. It can have small detrimental effects on the sound quality of the sub if the sub is made too stiff (reducing excursion ability and low frequency bandwidth). But in some applications the losses are offset by the ability to use extra power. An extra spider is not a bandaid for improper subsonic filter settings on your amp/DS with respect to the box tuning (should be 2-3 Hz lower than box tuning to avoid mechanical issues when the port unloads).
Internal Lead: This option is for 8 lead per coil, increasing the current flow from coil to terminals. It is sandwiched between the spiders to keep it linear and from flopping around under extreme excursion.
Plus Coil Pack: This option adds an extra spider and the larger/higher power handling Omega/TeamV3 coil. This well bump thermal capacity from 3500W to 4500W or more depending on other options and application. The extra spider helps keep the additional moving mass and power under control while the coil has much higher current carrying capacity over the standard 4″ coils.
Speaker Terminals
We have two terminal options on selected subwoofers.
Our Standard Push terminal using 144 strand count sewn tinsel leads Or our new Hybrid+ lead system with ring terminal attachment for high power systems.
“Fi Terms & Conditions”
These are not mass produced items. Each and every order is built from the ground up. This is not by using pre made parts and bolting/gluing them together, far from. They are machined to exact tolerance for your given application. There is no mass produced magnet sitting on the shelf, your woofer is made for you, when you order. Sure others can produce drivers faster but our manufacturing goes much deeper giving greater control during manufacturing resulting in a ultra high performance regardless of the footprint.
As a result build time is typically 10-30 days. With the distance from USA to the UK this can be anywhere from 14-28 days till you receive your Fi subwoofer.
We can offer a faster service with additional freight charge to express. Typically 7 days. Please contact us about this before ordering.
Refunds, If your custom-built-item has not yet begun to be manufactured you will be charged a 5% processing fee for refunding your payment. If your speaker has begun to be manufactured, or is finished, but has not shipped, you will be charged a 30% refund fee. If the speaker has already shipped, you will be charged the 30% refund fee plus all applicable return shipping costs.If we sent you a faulty subwoofer, or was received damaged, you will still be liable for a 30% refund fee plus all applicable return shipping costs.
By reading these terms and conditions, you agree to wait for the item to be recieved. If order is delayed or if there are manufacturing delay or part shortage you will be notified in good time.
If you have anymore questions do not hesitate in contacting us.
| Weight | 36 kg |
|---|
Only logged in customers who have purchased this product may leave a review.
UK Delivery
All items ordered before 14.00pm are shipped the same day unless otherwise stated at the time of ordering. Orders placed after 14.00pm on a Friday will be shipped the following Monday (excluding bank holidays, in which case it will be the next working day). If the item is out of stock for whatever reason you will be emailed within 24hrs to inform you of this. Our site manages stock inventory so if it says ‘IN STOCK’ that means goods are available for immediate dispatch.
If an item shows the logo as ‘Next Day Delivery*’ this means the item is available for immediate dispatch for a next day service. If your complete order is not over £50 then the order will be sent on a Royal Mail service. If its over then it will be sent with the most economical next day service. If you are unclear then please contact us.
- Shipping will be calculated at the checkout.
- Free shipping available for customers in the UK mainland ONLY when orders are over £50.
- We use DPD for all UK next day deliveries (aswell as for orders over £50 if the weight exceeds 2kg) and Royal Mail Recorded Post for orders under 2kg.
Free Delivery
Free delivery is available to UK mainland addresses ONLY and excludes addresses in the Scottish Highlands & Islands and Northern Ireland. Free delivery is applicable to orders over £50.00 (inc vat) ONLY. This offer doesn’t necessarily mean your goods will be sent on a courier next day service. However assuming the weight exceeds 2kg your goods are usually sent via courier (DPD Local).
Guranteed 24 Hour
- Next Day Delivery - Over £50 Inc. VAT - Any weight - Free!
- Next Day Delivery - 2-5KG - £8.00
- Next Day Delivery - 5-20KG - £9.99
- Next Day Delivery - 20-30KG - £11.99
- Next Day Delivery - 30-40KG - £15.00
- Next Day Delivery - 45KG+ - £50.00
Economy
- Royal Mail 1st Class Recorded 1-3 working days - Upto 1KG - £4.45
- Royal Mail 1st Class Recorded 1-3 working days - Upto 1-2KG - £6.90
- Royal Mail 2nd Class Recorded 2-5 working days - 0-2KG - £3.95
Saturday
- Royal Mail Special Delivery Saturday - Upto 2KG - £14.00
- Courier Saturday - Upto 5KG - £15.95
- Courier Saturday - 5-20KG - £19.95
- Courier Saturday - 20-25KG - £22.95
Back Order
European & International Delivery
Finally we advise you to check the contents of the order with the inventory sent with the goods. In the rare instance that goods are missing, please contact us within 24 hours and we will happily send out the missing goods at no extra cost to you. If goods are damaged or faulty please inform us within 3 working days of receiving your order.
Please refer to our Terms and Conditions for more information.
Reviews
There are no reviews yet.