Buying two subwoofers instead of one is one of those home theater upgrades that can make a bigger difference than simply buying a larger, more powerful sub. RSL Speakers is making that route considerably cheaper for a limited time, offering two factory-new Speedwoofer 10E subwoofers for $575.

The Speedwoofer 10E normally sells for $339.34 each, meaning two would ordinarily cost $678.68. The promotion knocks $103.68 off the pair, bringing the effective price down to $287.50 per subwoofer. Free shipping is included within the contiguous United States, and buyers can choose black or white versions. RSL says quantities are limited and the promotion will remain available only while the designated inventory lasts.

For buyers in Australia, RSL is offering a slightly different version of the promotion: 15 percent off a pair of Speedwoofer 10Es, with shipping costs depending on location.

Why Two Speedwoofers Can Be Better Than One

The obvious temptation when shopping for bass is to put the entire budget toward the largest subwoofer possible. But adding a second subwoofer addresses a different problem.

Bass behaves unpredictably inside normal rooms. Depending on where the subwoofer and listening position are located, room modes can create areas where certain frequencies become excessively loud and others nearly disappear.

Adding a second properly positioned subwoofer can help smooth those variations, giving multiple seats more consistent bass instead of creating one particularly good listening position.

RSL highlights several advantages to using two 10Es:

• More consistent bass across multiple listening positions
• Greater overall output and available headroom
• More placement flexibility
• Better coverage in larger or open-plan rooms

That doesn't mean two inexpensive subs automatically outperform every larger single subwoofer. Placement, calibration, room size, and the frequencies you want to reproduce all matter. But for a living room or multi-seat home theater, dual subs can solve problems that simply adding more amplifier power cannot.

What You Get With the Speedwoofer 10E

RSL introduced the Speedwoofer 10E as a less expensive alternative to the Speedwoofer 10S MKII, while retaining many of the basic ideas used across the company's subwoofer lineup.

At its center is a 10-inch high-excursion woofer driven by a Class D amplifier rated at 300 watts RMS and 800 watts peak. RSL specifies an anechoic frequency response of 26Hz to 200Hz, ±3dB, while estimating extension to roughly 22Hz once typical room gain is factored in.

The cabinet uses RSL's rear-vented Compression Guide design, which divides and braces the interior while directing the driver's rear output toward the port. The enclosure uses 3/4-inch MDF panels with a laminated one-inch front baffle.

Other specifications include:

• Variable 30Hz–200Hz low-pass filter
• Continuously variable 0–180-degree phase control
• RCA line-level inputs
• Automatic power mode
• 15.5 x 15 x 15.75-inch cabinet
• 38-pound weight

The 10E is therefore relatively compact by modern high-output subwoofer standards, which could also make finding locations for two of them easier than trying to accommodate a pair of much larger 12- or 15-inch models.

What the Speedwoofer 10E Is Designed to Do

The Speedwoofer 10E is designed to add substantial low-frequency impact without requiring the larger cabinet or higher price associated with more powerful subwoofers. Its 10-inch high-excursion driver and 300-watt RMS amplifier are intended to handle the bass demands of both music and movies while remaining compact enough for typical living rooms and dedicated home theaters.

The rear-vented enclosure uses RSL's Compression Guide design to help manage airflow and reinforce the cabinet. That approach allows the 10E to deliver useful output into the lower bass region while keeping the enclosure relatively easy to place.

Using two units can further improve the experience by increasing available output and reducing the strain placed on each subwoofer. It also gives owners more flexibility when experimenting with placement and calibration. Running two doesn't suddenly turn the 10E into a pair of giant infrasonic subwoofers, but it does give buyers more total output and more tools for dealing with room acoustics.

The Fine Print Matters

There are a few conditions worth knowing before ordering. The $575 price requires purchasing and keeping both subwoofers. Returning one removes the bundle discount, and RSL recalculates the retained unit at its normal $339.34 price. The company's standard $50-per-unit return fee also applies.

A 3.5 percent cancellation fee applies to orders canceled before shipment, and the promotion cannot be combined with other discounts. RSL's normal warranty, performance guarantee, and trial period still apply.

At $575 for the pair, the RSL Speedwoofer 10E offers an unusually compelling way to upgrade your system. Instead of spending the same money on one larger subwoofer, you can use two compact units to deliver smoother, more even bass throughout the room. For listeners who want deeper impact, better coverage, and a more immersive home-theater experience without overspending, the Speedwoofer 10E pair is an easy upgrade to recommend.