To connect a subwoofer to an AV receiver, run one subwoofer cable (a single RCA cable) from the receiver’s SUBWOOFER pre-out jack to the subwoofer’s LFE input. Then turn the subwoofer’s own crossover knob all the way up, tell the receiver a subwoofer is connected, and run the receiver’s room calibration.
This applies to powered subwoofers, the kind with their own amplifier and power cord. That’s what these receivers are built for. You don’t need a Y-splitter, special cable or speaker wire for this hookup. The two settings people most often miss are the speaker configuration, which has to include a subwoofer, and the subwoofer’s auto-standby. Auto-standby can switch the sub off during quiet movie scenes, so Sony says to turn it off.
What you need
- A powered subwoofer. Yamaha’s manual specifies a “subwoofer with built-in amplifier,” and Denon’s and Onkyo’s manuals describe the same thing.
- One subwoofer cable. This is a single RCA-to-RCA cable, sometimes sold as a “mono audio” or “subwoofer” cable. Sony’s manual calls it a monaural audio cable. Klipsch says any standard RCA or subwoofer cable will do. If you hear a hum, try a shielded subwoofer cable.
- A power outlet near where the subwoofer will sit.
Find the subwoofer jack on your receiver
The receiver’s subwoofer output is a line-level RCA jack, usually labeled SUBWOOFER or SUBWOOFER PRE OUT. All six of these popular receivers have two, so you can run one subwoofer or two:
| Receiver | Subwoofer outputs | With one subwoofer |
|---|---|---|
| Sony STR-DH590 | 2 (SUBWOOFER OUT) | Use either jack |
| Sony STR-DH790 | 2 (SUBWOOFER OUT) | Use either jack |
| Yamaha RX-V685 | 2 (SUBWOOFER 1 and 2 PRE OUT) | Up to two subwoofers supported |
| Denon AVR-S570BT | 2 | Either works. Both carry the same signal |
| Onkyo TX-NR6100 | 2 (SUBWOOFER PRE OUT) | Either works. Both carry the same signal |
| Denon AVR-S960H | 2 | Either works. Both carry the same signal |
Don’t plug the subwoofer into some other RCA output on the receiver. Klipsch notes it needs the dedicated subwoofer output.
Which input to use on the subwoofer
- An input labeled LFE: use it. Klipsch recommends the dedicated LFE jack, which on its subwoofers is the white RCA labeled L/LFE.
- Only a pair of line inputs (L and R): use the left or mono one. You don’t need a Y-splitter. Klipsch says a single cable is enough, and splitting into both inputs doubles the input voltage, which works out to about a 6 dB boost. That’s just extra volume, and you can get the same with the subwoofer’s level knob.
- Speaker-level (high-level) inputs: Klipsch lists these as an alternative, but its first choice with a home theater receiver is the RCA subwoofer output. Klipsch also warns that connecting more than one input type at once on modern subwoofers can damage the sub’s electronics.
How to connect and set up the subwoofer
- Unplug the receiver and the subwoofer. Yamaha says to unplug both power cables before you connect the subwoofer.
- Connect the cable. Plug one end into a SUBWOOFER output on the receiver and the other into the subwoofer’s LFE (or left/mono) input.
- Set the subwoofer’s crossover knob to maximum. Some subwoofers mark this position “LFE.” If yours has a digital low-pass filter, turn it off, as SVS suggests. If it has a “direct” or bypass mode, Denon says to use that instead. The receiver will handle the crossover.
- Set the phase to 0. SVS recommends starting there. If the bass sounds weak at your seat later, try the other phase setting.
- Set the power mode. Many subwoofers have Off, Auto and On. Sony says to turn off auto-standby when you watch movies, because the sub may go into standby and stop playing. If your sub keeps dropping out during quiet scenes, switch it to On.
- Set the subwoofer’s volume knob for calibration. Use your receiver’s recommendation: just before the mid-point (Sony), half (Yamaha), 12 o’clock (Denon), or more than half (Onkyo).
- Tell the receiver a subwoofer is connected. On Sony receivers, choose a speaker pattern ending in “.1,” such as 5.1. On Yamaha, set “Speaker” > “Configuration” > “Subwoofer” to “Use.” On Denon, set Subwoofer to “Yes” (Speaker Layout on the AVR-S570BT, Speaker Config. on the AVR-S960H). On Onkyo, make sure the subwoofer setting under “2. Speaker” is Yes.
- Run room calibration. Sony’s Auto Calibration, Yamaha’s YPAO, Denon’s Auto Setup or Audyssey, and Onkyo’s AccuEQ all measure the subwoofer’s distance and level. Audyssey on the AVR-S960H also works out the subwoofer’s crossover.
- Leave the subwoofer’s knobs alone afterward. Calibration measured the sub with those settings, and Denon says not to change the subwoofer’s volume after measuring. Adjust the bass level from the receiver instead.
How to tell it’s working
Play the receiver’s test tone and listen for the subwoofer channel. Sony’s T. TONE cycles through every speaker including the one shown as “SW,” and Denon’s Levels menu can play a tone from the subwoofer. Then play a movie scene with plenty of low bass. You should feel the subwoofer, not just hear it faintly.
Where to put the subwoofer
Placement is more forgiving than for the other speakers. Denon’s advice is to put one subwoofer “at a convenient location near the front speakers.” With two, Denon says to place them asymmetrically across the front of the room rather than as a mirrored pair. Wherever it ends up, rerun calibration after you move it.
Don’t be alarmed if calibration reports a subwoofer distance that doesn’t match your tape measure. Sony and Denon both say the measured subwoofer distance may differ from the actual one.
Receiver settings that affect the subwoofer
- Speaker size and crossover. The subwoofer plays the bass the receiver redirects from speakers set to “Small,” below the crossover frequency (80 Hz is the usual starting point). Speakers set to “Large” or “Full Band” keep their own bass.
- Subwoofer mode. Denon offers LFE (the default) and LFE+Main. Denon warns that with large front and center speakers in LFE mode, the subwoofer may not play for some signals or sound modes. LFE+Main keeps it playing.
- Sound mode. Some modes don’t use the subwoofer. On Sony receivers, “2ch Stereo” never sends sound to it.
- Headphones. Plugging headphones into the receiver mutes the speakers and the subwoofer output. Denon’s manual notes this.
If the subwoofer makes no sound
- Check that the subwoofer is plugged in, switched on and not in standby.
- Check the cable at both ends: receiver SUBWOOFER output to subwoofer LFE or left input.
- Confirm the receiver’s speaker setup includes a subwoofer (“.1” pattern, “Use” or “Yes”).
- Switch to a movie with a 5.1 or 7.1 soundtrack. If the sub works there but not with music, your speakers are probably set to Large. Choose Small or LFE+Main.
- Turn up the subwoofer’s volume knob, and check its crossover knob isn’t turned all the way down.
- Unplug any headphones.
For model-specific fixes, see our guides to a silent subwoofer on the Sony STR-DH590 and no-sound problems on the Denon AVR-S570BT. If you’re setting up a Denon AVR-S960H, our Audyssey setup guide covers the subwoofer prep for calibration.
Quick answers
Do I need a Y-splitter?
No. Klipsch says a single standard cable is all you need. A Y-splitter into both inputs just raises the level by about 6 dB.
Can I connect two subwoofers?
Yes, on all six receivers above. Connect one subwoofer to each output. Sony notes you can only run two subwoofers this way if the receiver has a second subwoofer output.
Can I use a passive subwoofer?
Not directly. The subwoofer jack carries a line-level signal meant for a subwoofer with its own amplifier. Yamaha’s manual asks for a subwoofer with a built-in amplifier.
Should the subwoofer’s crossover knob match the receiver’s crossover?
No. Turn the subwoofer’s knob to maximum and set the crossover in the receiver. Klipsch, SVS, Yamaha and Denon all give this advice when the receiver handles bass management.
For the manufacturers’ own instructions, see Klipsch’s guide to subwoofer controls and Denon’s Bass settings page for the AVR-S960H.