Why subwoofer placement matters
Low frequencies have wavelengths of several meters, so they reflect off every wall and create room modes – peaks where bass booms and nulls where it almost disappears. Moving the subwoofer even a meter can change bass at your seat by 10 dB or more. Placement and alignment with your main speakers matter more than the sub's price.
Time alignment and phase
Sound travels about 1,125 ft (343 m) per second – roughly 1 ms per foot. If the subwoofer is farther from your seat than the main speakers, its output arrives later. Around the crossover frequency, where both play together, that delay shifts phase and can cancel bass.
Delay (ms) = distance difference (ft) ÷ 1.125 · Phase (°) = delay (s) × crossover (Hz) × 360
Proven placement positions
| Subwoofers | Placement | Result |
|---|
| 1 | Front corner or found by "sub crawl" | Maximum output; uneven across seats |
| 2 | Front & rear wall midpoints, or ¼ and ¾ along the front wall | Much smoother bass for several seats |
| 4 | Midpoint of each wall, or four corners | Smoothest bass across a seating area |
The subwoofer crawl
- Place the subwoofer on your main listening seat.
- Play bass-heavy music or a bass sweep.
- Crawl around the floor along the walls where the sub could go.
- Where the bass sounds smoothest and fullest, place the sub.
Setting up the receiver
- Set speakers to "small" and use a crossover of 80 Hz as a starting point.
- Enter accurate distances, or run room correction with a microphone.
- Try the sub's phase switch or dial while listening near the crossover frequency.
- Level-match with a sound level meter, then fine-tune by taste.
Frequently asked questions
Where is the best place for a subwoofer?
Often a front corner or along the front wall, but the best spot depends on your room – the subwoofer crawl finds it quickly.
Should the subwoofer phase be 0 or 180?
It depends on distances. Try both and keep the setting that gives more bass around the crossover frequency.
How much delay does a subwoofer need?
About 1 ms per foot of distance difference between the sub and the main speakers.
Are two subwoofers better than one?
Yes for even bass – two or four subs smooth out room modes across seats.
What crossover should I use?
80 Hz is the THX standard and a good start for most speakers.
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Last updated: October 28, 2026
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