Most subwoofers announce themselves. They boom, they thump, they draw attention to their presence. The REL S/812 does something more sophisticated—it disappears. At $2,499, this British-designed subwoofer exists to extend your speakers' bass response so seamlessly that you forget it's there. You just hear music, complete and whole.
The REL Philosophy
REL approaches subwoofers differently than home theater brands. Where others optimize for maximum SPL and room-shaking impact, REL optimizes for musical integration. The S/812 isn't designed to impress—it's designed to complete whatever speakers you already own.
This philosophy manifests in their signature high-level connection. Rather than connecting to a preamp output (low-level), REL recommends connecting directly to your amplifier's speaker terminals. This ensures the subwoofer receives the exact same signal—including your amplifier's sonic character—as your main speakers.
Driver and Amplifier Technology
The S/812 features REL's 12-inch aluminum-reinforced ContinuousCast driver, designed for speed and precision rather than maximum excursion. The 500-watt Class D amplifier (NextGen5) provides ample power while running cool and efficient.
A 12-inch down-firing passive radiator extends low-frequency response and increases output without adding driver cost. The sealed cabinet eliminates port noise and provides controlled, tight bass response.
Speed Matters
Audiophile subwoofers differentiate themselves through speed—how quickly the driver responds to transients. The S/812's lightweight aluminum cone and powerful motor structure enable exceptional transient response. Upright bass attacks emerge distinctly. Kick drums have impact without lingering. The bass starts and stops when the music does.
Integration: The Art of Disappearing
Setting up the S/812 requires patience and careful adjustment. REL provides independent gain controls for high-level and low-level inputs, plus a continuously variable crossover. The goal is finding settings where you can't localize the subwoofer—where bass simply exists as part of the music.
In my reference system with floor-standing speakers, this took several hours of micro-adjustment. The result was worth the effort. My main speakers suddenly sounded larger, fuller, and more authoritative without any sense of "boom" or "thump" from a subwoofer.
Music Performance
String bass has weight and texture. Pipe organ pedal notes emerge from the foundation with authority. Electronic music has presence without overwhelming detail. The S/812 handles every genre with equal competence because it's not imposing a character—it's extending what exists.
Critically, the S/812 improves the perceived performance of the midrange. By handling deep bass, your main speakers operate more comfortably, reducing intermodulation distortion and improving clarity throughout the frequency range.
Home Theater Capability
While optimized for music, the S/812 handles home theater content admirably. The low-level LFE input works alongside the high-level connection, providing dedicated home theater bass when needed. Action movie explosions and rumble are convincing, though dedicated home theater subs will produce more absolute output.
Build Quality and Finish
The S/812 is available in Piano Black or White lacquer finishes—genuine lacquer, not vinyl wrap. The construction is solid, the finish is impeccable, and the overall impression is of serious audio equipment, not budget furniture.
Pros and Cons
Pros:
- Exceptional musical integration and speed
- High-level connection for amplifier matching
- 500W Class D amplifier with headroom
- Genuine lacquer finish options
- Improves main speaker performance
- Tight, controlled bass without boom
- Comprehensive adjustment options
Cons:
- $2,499 price is significant
- Requires careful setup for best results
- Not the loudest option for home theater
- Musical focus may disappoint bass-heads
- Single subwoofer may not fill very large rooms
Final Verdict
The REL Acoustics S/812 is for listeners who value seamless integration over maximum impact. It's for audiophiles who want their subwoofer to enhance rather than dominate. It's for those who understand that the best bass is often the bass you don't consciously notice.
If your priority is shaking the room for movie explosions, look elsewhere. If you want music reproduction that's simply more complete, the S/812 delivers exactly that.
Rating: 9.1/10 - The audiophile's subwoofer that serves the music.