SBIR Calculator
Drag your speaker. See the exact bass nulls from front, side, and rear walls — then hear them.
Room lengthm
Room widthm
Speaker from left wallm
Speaker from front wallm
- Rear wall21 Hzwall behind the listening area (bottom of plan)4.00 m to wall · -8 dB dip
- Right wall29 Hzright side of the plan3.00 m to wall · -9 dB dip
- Front wall86 Hzwall the speakers face away from (top of plan)1.00 m to wall · -14 dB dip
- Left wall86 Hzleft side of the plan1.00 m to wall · -14 dB dip
Hear the dip
0:00 / 0:00
Your speaker is 1.00 m from the left wall, creating a -14 dB null at 86 Hz.
Preview only — open the 3D builder for full placement, treatment, and analysis.
Frequently asked questions
- What is SBIR (speaker boundary interference response)?
- SBIR is the cancellation that happens when sound from a speaker reflects off a nearby wall and arrives at the listener out of phase — typically a quarter wavelength later. The null frequency is f = c / (4 · d), where c is the speed of sound (343 m/s) and d is the distance to the reflecting boundary.
- How do I avoid SBIR nulls from the front wall?
- Either place the speaker very close to the wall (under 0.2 m / 8 in, with boundary EQ compensation) or far from it (over 1 m / 3.3 ft). Distances in between push the cancellation into the critical midbass region.