Where do you mount a subwoofer in a car?

In most vehicles, the best bass is achieved with a sealed or ported enclosure placed in the trunk or cargo area, or with a compact sub mounted under a rear seat or on the rear deck. The location affects bass tightness, space, and installation practicality.

Common mounting locations

Car audio installers commonly categorize mounting spots by how much space they consume and how they influence cabin acoustics. Here are the typical choices people consider.

• Trunk or cargo area in sedans, wagons, and many SUVs — ideal for large enclosures and strong bass with minimal cabin resonance.


• Under the rear seat — space-saving and keeps bass closer to the cabin, but may limit enclosure size and require careful mounting depth.


• Rear deck or parcel shelf (behind the rear seats in hatchbacks and some coupes) — convenient for compact subs and can leverage the car’s interior air path for impact.


• Spare tire well with a compact enclosure — a clean look that preserves most trunk space, though it may require trimming the spare compartment and managing heat/vibration.

Not every car supports every option. Check clearance, wire routing, and safety considerations such as airbags and seat mechanics before choosing a location.

Trunk and cargo-area mounting

Mounting in the trunk usually involves a sealed or ported enclosure. This spot offers plenty of air volume for deep bass and straightforward wiring, but can introduce rattles if the trunk isn’t damped well and may reduce cargo space.

• Pros: strong, deep bass; easy power routing to the amplifier; ample space for larger enclosures.


• Cons: potential cargo-area rattles; reduces available trunk space unless custom mounting is used.

To maximize performance and minimize rattles, add damping material and secure the enclosure firmly.

Under-seat and compact options

Under-seat setups save space and keep the woofer close to the cabin, which can improve perceived bass in some vehicles. They require shallow enclosures and precise mounting to avoid interference with seats and passengers.

• Pros: preserves trunk space; shorter signal path to the cabin; easier routing of power and signal wires.


• Cons: limited enclosure size; potential heat and clearance issues under seats.

Under-seat subwoofers are a popular compromise for small cars or when trunk space is at a premium.

Enclosure types and mounting considerations

Choosing between sealed, ported, or infinite-baffle designs and how you mount them affects sound quality, size, and vibration control. Here are the basics to guide placement.

• Sealed enclosures are compact and deliver tight, controlled bass; they pair well with trunk or under-seat mounting but require careful tuning for cabin size.


• Ported enclosures provide more output and deeper bass but need space and proper placement to avoid port noise in the cabin.


• Infinite-baffle or free-air designs rely on the vehicle’s panels for support; useful when space is extremely tight, but response can be uneven without proper integration.

Whichever enclosure you choose, ensure a good seal, appropriate damping, and consideration of how vibrations will be managed across the car’s panels.

Wiring, safety, and install tips

Aftermarket subwoofer installations require careful power routing, proper grounding, and sound integration with the vehicle’s electronics. Follow best practices to stay safe and maximize performance.

• Run a dedicated power wire from the battery with an in-line fuse near the battery; ground to a clean chassis point near the amplifier.


• Use a suitable amplifier with adequate power and proper gain staging; keep signal wiring (RCA cables) away from power cables to minimize noise.


• Secure all wiring, avoid hot surfaces, and apply vibration damping to reduce rattles and wear.


• Disconnect the vehicle battery while making electrical connections to prevent shorts and accidental airbag deployment.

Plan routes to minimize interference with airbags, sensors, and seat mechanics, and consider any warranty implications of aftermarket installations.

Summary

For most cars, the trunk or cargo area offers the best balance of bass output, space, and ease of installation, with under-seat and rear-deck options serving tighter or more space-conscious setups. The right choice depends on vehicle type, enclosure size, and how you want the sub to integrate with the cabin’s sound. Proper enclosure, wiring, and vibration management are essential to achieving clean, powerful bass without unwanted rattles.

How to properly mount a subwoofer in a car?

Mount the subwoofer and amplifier
Your trunk or underneath a seat are typically the best spots. Then, use brackets or a custom enclosure to firmly anchor the subwoofer. For a separate amplifier, pick a well-ventilated area to help prevent overheating and secure it with screws or mounting kits.

Can a stock alternator handle a subwoofer?

Yes you absolutely can, but this doesn't mean it will fix voltage drop or light dim issues. Absolutely, even if all you need is say 9awg to handle the stock alternator. If you get large draws of current you will drop a lot of voltage on small wire vs having a very unrestricted flow.

Where not to place a subwoofer?

Avoid Walls and Corners
If you have to place your sub along a wall, try to find a spot away from the corner and pull the sub 12 to 18 inches away from the wall to minimize bass build-up.

Where is the best place to put a subwoofer in a car?

The best place for a car subwoofer is often in the trunk, especially in the corners, for the best bass performance and to save passenger space. For a more compact solution that saves space and wiring, consider a subwoofer under a seat, which can also be easier to install. The ideal placement depends on the type of vehicle and your priorities for sound and cargo space. 
This video explains where to place a subwoofer in a car for maximum bass: 53sAudio RevampYouTube · May 13, 2025
Trunk

• Corner placement: Placing the subwoofer enclosure in a corner of the trunk is a popular and effective method called "corner loading". It helps reinforce the bass sound waves by reflecting them off the back and side walls of the vehicle. 
• Facing the back: Position the subwoofer to face the rear of the car. This allows the sound to reflect off the back of the vehicle, boosting the bass output in the cabin. 
• Upward or upward-firing: In a hatchback or SUV, placing the subwoofer upward can also work well, helping to blend the bass more evenly throughout the cabin. 
• Pros: Provides powerful bass and surround sound, and keeps the subwoofer out of the way of passengers. 
• Cons: Requires running wiring from the front of the car to the trunk. 

This video demonstrates how to find the optimal subwoofer position in a car: 1mCarAudioFabricationYouTube · Jan 2, 2017
Under a seat

• Placement: Install a compact subwoofer under one of the front seats. 
• Pros: Saves a lot of space, simplifies wiring, and can provide more vibration since it's closer to the passengers. 
• Cons: Only suitable for smaller, powered subwoofers, as many boxes are too large. 

You can watch this video to learn how to install a powered subwoofer under a seat in your car: 52sCRUTCHFIELDYouTube · Apr 19, 2023
Other options

• Spare tire well: A skilled installer can place a subwoofer in the spare tire well, which is a good option for keeping it hidden. 
• Rear deck: In some sedans, a subwoofer can be installed through the rear deck or a "ski pass-through" opening. 

This video shows how to install a subwoofer in the spare tire well: 59sAutomotive SuperstoreYouTube · Jul 29, 2025