Room Modes in a 22x28 ft Room with an 8 ft Ceiling

A 22 by 28 ft room with an 8 ft ceiling suits a dedicated home theater or media room. Its lowest room mode sits at 20.1 Hz, set by the 28 ft length, the lowest note the room itself reinforces before any speaker or sub plays a thing.

Checked against every mode below 200 Hz, this room scores 70/100, a decent score, typical for a room this shape. The clearest issue is that two of its dimensions reinforce the same note near 100.5 Hz.

Lowest mode
20.1 Hz
Modes under 200 Hz
167
Schroeder frequency
107 Hz
Modal score
70/100

Mode spectrum

Mode spectrum · log frequency · stem height ≈ relative energy
Axial Tangential Oblique Cluster

3 dense clusters (≤5 Hz apart) — overlapping resonances are harder to treat evenly.

Each line is one standing wave. Axial modes, the strongest kind, stand tallest; tight bunches and wide empty stretches are where the bass will sound uneven.

Axial modes by dimension

Dimension1st2nd3rd4th
Length (28 ft)20.1 Hz40.2 Hz60.3 Hz80.4 Hz
Width (22 ft)25.6 Hz51.2 Hz76.7 Hz102.3 Hz
Ceiling height (8 ft)70.3 Hz140.7 Hz211 Hz281.3 Hz

What this means for your room

  • The lowest room mode is 20.1 Hz, set by the 28 ft length.
  • Your 28 ft length and 22 ft width both resonate near 100.5 and 179.0 Hz, so bass at those notes will be much louder than its neighbours.
  • Your 28 ft length and 8 ft ceiling height both resonate at 140.7 Hz, so bass at that note will be much louder than its neighbours.
  • The proportions (1 : 2.75 : 3.50) fall inside the Bolt area, the range of room ratios that spreads modes most evenly.
  • Below about 107 Hz (the Schroeder frequency) individual modes shape the sound; above it, reflections and reverb matter more.

The modes from your 28 ft length and 22 ft width land on top of each other near 100.5 Hz. That stack means one specific low note gets reinforced twice, so it jumps out over everything nearby.

For a home theater, expect that stacked note to color explosions and sub-bass hits unevenly rather than smoothly. For a music room, it means you cannot fully trust what you hear in the low end at the listening position, since a note that sounds loud in the room may be perfectly balanced on the recording.

The room's proportions (1 : 2.75 : 3.50, height to width to length) fall inside the Bolt area, the range acousticians consider best for spreading modes evenly. That is a genuine advantage of this room's shape, not something you can add later with treatment.

How to fix it, in order

  1. Treat the four floor-to-ceiling corners first; they are common to every mode this room produces, and your ceiling height is part of the problem.
  2. At 100.5 Hz the quarter wavelength is about 2.8 ft, deeper than any practical panel, so a porous trap alone will not fully absorb that note. Build corner traps as thick as you can fit (6 to 12 in, straddling the corner with an air gap behind) to take the edge off, then handle the note itself with a membrane or pressure trap tuned near it, careful seat position, and more than one subwoofer with EQ.
  3. Move your listening position off-center along the 28 ft length; roughly 10.6 ft from the front wall (38% back) is a common starting spot before fine-tuning.
  4. Walk the subwoofer around the front of the room while playing a bass-heavy track and listen from your seat: corner placement is loudest but least even, and a second sub or an off-corner spot often fills in this room’s weak points.
  5. Once traps are in, measure with REW from the listening position. Focus on frequencies below 107 Hz (this room's Schroeder frequency); that is where individual modes, not general reverb, are running the show.

These numbers assume an empty rectangular 22x28 room with hard walls. Draw your real room, add furniture and speakers, and simulate the bass at your seat.

Model this room in 3D

Every mode below 200 Hz

This room has 167 modes below 200 Hz, 18 axial, 80 tangential and 69 oblique. Read the axial rows as the ones you will hear most clearly. Tangential and oblique modes add texture but usually only become audible when they land close to an axial mode.

FrequencyTypeMode (length, width, height)
20.1 Hzaxial(1,0,0)
25.6 Hzaxial(0,1,0)
32.5 Hztangential(1,1,0)
40.2 Hzaxial(2,0,0)
47.6 Hztangential(2,1,0)
51.2 Hzaxial(0,2,0)
55 Hztangential(1,2,0)
60.3 Hzaxial(3,0,0)
65.1 Hztangential(2,2,0)
65.5 Hztangential(3,1,0)
70.3 Hzaxial(0,0,1)
73.1 Hztangential(1,0,1)
74.8 Hztangential(0,1,1)
76.7 Hzaxial(0,3,0)
77.5 Hzoblique(1,1,1)
79.1 Hztangential(3,2,0)
79.3 Hztangential(1,3,0)
80.4 Hzaxial(4,0,0)
81 Hztangential(2,0,1)
84.4 Hztangential(4,1,0)
84.9 Hzoblique(2,1,1)
86.6 Hztangential(2,3,0)
87 Hztangential(0,2,1)
89.3 Hzoblique(1,2,1)
92.6 Hztangential(3,0,1)
95.3 Hztangential(4,2,0)
95.8 Hzoblique(2,2,1)
96.1 Hzoblique(3,1,1)
97.6 Hztangential(3,3,0)
100.5 Hzaxial(5,0,0)
102.3 Hzaxial(0,4,0)
103.7 Hztangential(5,1,0)
104.1 Hztangential(0,3,1)
104.3 Hztangential(1,4,0)
105.8 Hzoblique(3,2,1)
106 Hzoblique(1,3,1)
106.8 Hztangential(4,0,1)
109.8 Hzoblique(4,1,1)
109.9 Hztangential(2,4,0)
111.1 Hztangential(4,3,0)
111.6 Hzoblique(2,3,1)
112.7 Hztangential(5,2,0)
118.4 Hzoblique(4,2,1)
118.7 Hztangential(3,4,0)
120.3 Hzoblique(3,3,1)
120.6 Hzaxial(6,0,0)
122.6 Hztangential(5,0,1)
123.3 Hztangential(6,1,0)
124.1 Hztangential(0,4,1)
125.3 Hzoblique(5,1,1)
125.8 Hzoblique(1,4,1)
126.4 Hztangential(5,3,0)
127.9 Hzaxial(0,5,0)
129.4 Hztangential(1,5,0)
130.1 Hztangential(4,4,0)
130.5 Hzoblique(2,4,1)
131 Hztangential(6,2,0)
131.5 Hzoblique(4,3,1)
132.9 Hzoblique(5,2,1)
134 Hztangential(2,5,0)
138 Hzoblique(3,4,1)
139.6 Hztangential(6,0,1)
140.7 Hzaxial(0,0,2)
140.7 Hzaxial(7,0,0)
141.4 Hztangential(3,5,0)
141.9 Hzoblique(6,1,1)
142.1 Hztangential(1,0,2)
142.9 Hztangential(6,3,0)
143 Hztangential(0,1,2)
143 Hztangential(7,1,0)
143.4 Hztangential(5,4,0)
144.4 Hzoblique(1,1,2)
144.7 Hzoblique(5,3,1)
145.9 Hztangential(0,5,1)
146.3 Hztangential(2,0,2)
147.3 Hzoblique(1,5,1)
147.9 Hzoblique(4,4,1)
148.5 Hzoblique(2,1,2)
148.7 Hzoblique(6,2,1)
149.7 Hztangential(0,2,2)
149.7 Hztangential(7,2,0)
151 Hztangential(4,5,0)
151 Hzoblique(1,2,2)
151.4 Hzoblique(2,5,1)
153 Hztangential(3,0,2)
153.5 Hzaxial(0,6,0)
154.8 Hztangential(1,6,0)
155 Hzoblique(2,2,2)
155.2 Hzoblique(3,1,2)
157.3 Hztangential(7,0,1)
157.9 Hzoblique(3,5,1)
158.1 Hztangential(6,4,0)
158.6 Hztangential(2,6,0)
159.3 Hzoblique(6,3,1)
159.3 Hzoblique(7,1,1)
159.7 Hzoblique(5,4,1)
160.2 Hztangential(0,3,2)
160.2 Hztangential(7,3,0)
160.8 Hzaxial(8,0,0)
161.4 Hzoblique(3,2,2)
161.5 Hzoblique(1,3,2)
162 Hztangential(4,0,2)
162.6 Hztangential(5,5,0)
162.8 Hztangential(8,1,0)
164 Hzoblique(4,1,2)
164.9 Hztangential(3,6,0)
165.2 Hzoblique(2,3,2)
165.4 Hzoblique(7,2,1)
166.6 Hzoblique(4,5,1)
168.7 Hztangential(8,2,0)
168.8 Hztangential(0,6,1)
169.9 Hzoblique(4,2,2)
170 Hzoblique(1,6,1)
171.2 Hzoblique(3,3,2)
172.9 Hztangential(5,0,2)
173.1 Hzoblique(6,4,1)
173.2 Hztangential(4,6,0)
173.5 Hzoblique(2,6,1)
173.9 Hztangential(0,4,2)
173.9 Hztangential(7,4,0)
174.7 Hzoblique(5,1,2)
175 Hzoblique(7,3,1)
175.1 Hzoblique(1,4,2)
175.5 Hztangential(8,0,1)
175.8 Hztangential(6,5,0)
177.2 Hzoblique(5,5,1)
177.3 Hzoblique(8,1,1)
178.1 Hztangential(8,3,0)
178.5 Hzoblique(2,4,2)
179 Hzaxial(0,7,0)
179.2 Hzoblique(3,6,1)
179.3 Hzoblique(4,3,2)
180.2 Hztangential(1,7,0)
180.3 Hzoblique(5,2,2)
180.9 Hzaxial(9,0,0)
182.7 Hztangential(9,1,0)
182.8 Hzoblique(8,2,1)
183.4 Hztangential(5,6,0)
183.5 Hztangential(2,7,0)
184.1 Hzoblique(3,4,2)
185.3 Hztangential(6,0,2)
187 Hzoblique(4,6,1)
187 Hzoblique(6,1,2)
187.6 Hzoblique(7,4,1)
188 Hztangential(9,2,0)
188.9 Hztangential(3,7,0)
189.1 Hzoblique(5,3,2)
189.3 Hzoblique(6,5,1)
190.1 Hztangential(0,5,2)
190.1 Hztangential(7,5,0)
190.6 Hztangential(8,4,0)
191.2 Hzoblique(1,5,2)
191.5 Hzoblique(8,3,1)
191.6 Hzoblique(4,4,2)
192.2 Hzoblique(6,2,2)
192.3 Hztangential(0,7,1)
193.4 Hzoblique(1,7,1)
194.1 Hztangential(9,0,1)
194.3 Hzoblique(2,5,2)
195.2 Hztangential(6,6,0)
195.7 Hzoblique(9,1,1)
196.2 Hztangential(4,7,0)
196.4 Hzoblique(5,6,1)
196.5 Hztangential(9,3,0)
196.5 Hzoblique(2,7,1)
198.9 Hztangential(7,0,2)
199.4 Hzoblique(3,5,2)

Questions about 22x28 rooms

Will a 22x28 room work for a home theater?
This size suits a dedicated home theater or media room, though the 70/100 modal score signals some work ahead, mainly because two of its dimensions reinforce the same note near 100.5 Hz.
Where should I put bass traps in a 22x28 room?
Start in the four floor-to-ceiling corners; every mode in this room peaks there. The 100.5 Hz mode itself would need about 2.8 ft of depth to fully absorb, more than any panel can give, so build corner traps as thick as you can fit (6 to 12 in) and pair them with a membrane trap tuned near 100.5 Hz.
What subwoofer size is right for a 22 by 28 ft room?
There is no fixed sub size tied to 616 sq ft; that number mostly sets this room's mode frequencies (167 of them under 200 Hz). At this size you will want more headroom than a small room needs, and two subwoofers usually beat one at keeping bass even from seat to seat.
Why does my 22x28 room have one loud bass note?
The short answer for this room: two of its dimensions reinforce the same note near 100.5 Hz. Bass unevenness like that is built into the shape of the room and shows up regardless of what speakers or sub you use.
How do I fix bass problems in a 22x28 room?
Put bass traps in the four floor-to-ceiling corners first, as thick as you can fit (6 to 12 in) plus a membrane trap tuned near 100.5 Hz, since that note's own quarter wavelength (about 2.8 ft) is too deep for any panel. From there, move your seat to about 10.6 ft from the front wall, then measure with REW below 107 Hz to see what still needs work.

Similar room sizes

How these numbers are calculated

Modes use the rectangular-room equation f = (c/2)·√((nx/L)² + (ny/W)² + (nz/H)²) with c = 343 m/s, for an empty room with rigid walls. The Schroeder frequency is fs = 2000 x sqrt(RT60 / V), assuming RT60 = 0.4 s. The modal score starts at 100 and subtracts penalties for stacked modes, density dips, gaps, proportions outside the Bolt area and dimension multiples. Doors, openings and furniture shift real rooms away from these values, which is what the room mode calculator and the 3D editor are for.