Does the Klipsch R-121SW work with the Denon AVR-X1800H?
Verdict
Yes
The R-121SW has a line-level input, and the AVR-X1800H's 2 subwoofer outputs feed it.
Connection
Line-level
Sub out to its LFE input
Sub outputs
2
On the AVR-X1800H
Amplifier
200 W
Built into the R-121SW
How to connect them
- Run a subwoofer cable from the AVR-X1800H's sub out 1 to the R-121SW's line-level input.
- Set speakers to Small with an 80 Hz crossover.
- Run Audyssey MultEQ XT with its microphone at your seat.
Plan the R-121SW and AVR-X1800H in your own room.
Draw your room in 3D, place both, and see every connection checked and how loud they play at your seat. Designing is free.
The specs that decide it
Klipsch R-121SW
- Amplifier
- 200 W
- Low end
- 28 Hz
- Inputs
- Line
- MSRP
- $650 each (MSRP, September 2026)
Denon AVR-X1800H
- Amplifier channels
- 7
- Subwoofer outputs
- 2
- MSRP
- $849 each (MSRP, September 2026)
Questions about the R-121SW and AVR-X1800H
- Does the R-121SW connect to the AVR-X1800H?
- Yes. The R-121SW has a line-level input, and the AVR-X1800H's 2 subwoofer outputs feed it.
- What crossover setting should I use with the R-121SW?
- Set your speakers to Small with an 80 Hz crossover: the standard starting point for a receiver and subwoofer, whichever subwoofer you use.
- How do I connect the R-121SW to the AVR-X1800H?
- Run a subwoofer cable from the AVR-X1800H's sub out 1 to the R-121SW's line-level input.
Swap one of them
References
- Klipsch R-121SW: Spec sheet, assets.klipsch.com, retrieved September 15, 2026
- Klipsch R-121SW: Retailer listing, bestbuy.com, retrieved September 15, 2026
- Denon AVR-X1800H: Spec sheet, denon.com, retrieved September 15, 2026
- Denon AVR-X1800H: Manufacturer product page, denon.com, retrieved September 15, 2026
- Denon AVR-X1800H: Manufacturer product page, denon.com, retrieved September 15, 2026 (2)
- Denon AVR-X1800H: Owner's manual, manuals.denon.com, retrieved September 15, 2026
- Denon AVR-X1800H: Dimensional drawing, manuals.denon.com, retrieved September 15, 2026
Specs verified against the manufacturer's published data. Last checked September 15, 2026.
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