Focal ISUB Twin Sub Powerful Compact Passive Underseat Car Subwoofer 2x 100w RMS
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The Focal ISUB TWIN is a pair of passive underseat subwoofers rated at 2 x 100W RMS (200W max each) at 2 ohms, featuring double ferrite drivers and aluminium cones. They are part of Focal's car audio subwoofer range and require an external amplifier to operate.
This listing is for the passive ISUB TWIN. Focal also offer the ISUB Active, an amplified underseat subwoofer with a built-in amp rated at 130W RMS.
As passive subwoofers they require an external amplifier. Focal recommend pairing them with the Focal Impulse 4.320, which leaves two front channels free for a pair of door speakers.
Key specifications
- Type: twin passive underseat subwoofers (supplied as a pair)
- Power handling: 100W nominal, 200W maximum per subwoofer
- Impedance: 2 ohms; DC resistance 1.9 ohms
- Sensitivity: 83 dB
- Cone: aluminium with butyl surround, double ferrite driver
- Voice coil: 20 mm (0.8 in), 4-layer copper
- Dimensions: 260 x 240 x 80 mm (10 1/4 x 9 1/2 x 3 1/8 in)
- Net weight: 2.7 kg (6 lbs)
ISUB TWIN underseat passive subwoofer
The ISUB TWIN pair significantly improves bass impact in a car audio installation, thanks to double ferrite drivers and a heavy-duty aluminium cone. Front grilles promote sound dispersion throughout the cabin.
These subwoofers slide under the seats without any car modifications. Attach them using the self-adhesive strips provided — no tools needed — or screw them to the floor if preferred. Check available under-seat clearance before purchasing.
Running-in period
Once installed, run the ISUB TWIN at a medium volume setting with music covering the full frequency range (sub-bass through treble). Maintain this for a few weeks before expecting full performance.
Key points
- Ultra-compact twin subwoofers supplied as a pair
- High-fidelity sound reproduction
- Easy, invisible integration — no car modifications required
- Self-adhesive strips included
- Compatible with all Focal Car Audio and Focal Inside products
Explore the full range in Focal Inside.
Specification
| Sensitivity | 83dB |
|---|---|
| Cone | Aluminium |
| Surround | Butyl |
More specs
| |
What's Included
- ISUB x2
- Velcro strips
Check the available space before installing in the desired locations.
Focal
About the Focal ISUB Twin
From our tech experts at CEN
A Focal Inside subwoofer, handling 100w RMS.
Who it suits
Drivers building a system where the bass has to keep pace with a capable front stage. the Inside range is designed to drop straight into specific vehicles.
Our tech experts advise
A subwoofer is only as good as its enclosure and the amplifier behind it: volume and tuning decide what you hear. We build enclosures to suit both driver and vehicle at our Beeston workshop. Installation is priced per vehicle, so get in touch with your make, model and year and we will confirm what it needs. See car audio installation.
Explore the full Focal range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Focal
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
- 3
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Bring it to our Beeston workshop and we do the rest.
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Plug & Play Kits
Configure the solution best suited to your needs in just a few clicks.
Focal Inside Series
The Focal Inside offer is aimed at all drivers wishing to replace their car's original system with a hi-fi quality Plug & Play solution that integrates easily, without modifying the interior. Different configurations are available by brand (over 50 brands), by car model (1000 vehicle models).
Focal Car Audio
Deliver exceptional sound clarity and precision for your vehicle.
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Frequently Asked Questions
Q: Do I need an amplifier for this subwoofer?
A: Yes, unless it is an active (powered) subwoofer with a built-in amplifier. Passive subwoofers need an external amplifier matched to the RMS power and impedance shown in the Specification tab.
Q: What does RMS power mean?
A: RMS is the continuous power a subwoofer can handle, and it is the number that matters when matching an amplifier. Peak or max figures describe short bursts only. Match your amplifier output to the RMS rating in the Specification tab.
Q: Can CEN build or supply an enclosure and fit everything?
A: Yes. CEN supplies enclosures and offers professional installation from our Nottingham premises, including amplifier wiring. Contact us to discuss your build.
Q: Which amplifier should I use with the Focal ISUB TWIN?
A: Focal recommends the Impulse 4.320 amplifier. The ISUB TWIN uses two of its channels, leaving the two front channels free for a pair of door speakers. The subwoofers are 2 ohm and handle 100W nominal each.
Q: Will the ISUB TWIN fit under my seats?
A: Each subwoofer measures 260 x 240 x 80 mm. They are designed to slide under most seats, but check the available space in your vehicle before installation.
Q: Do I need to modify my car to fit the ISUB TWIN?
A: No. They install without any modifications, attaching with the supplied self-adhesive (Velcro) strips, or they can be screwed to the floor if you prefer.
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