room size resonance mismatch

[skyfly]

5.15 meters from the wall behind the speakers to the wall behind the listening sofa
(the left side - in the view of the listener - is open to some additional space, another room, kitchen, and hallway)

(343/5.15)*(1/2) = 33.3 Hz

However, the room resonance frequency when L and R speakers are played together is 37 Hz. About 11 percent mismatch.

 

[skyfly]

Any insights?

Can such a sharp long-lasting peak be due to a defective bass reflex system of the loudspeakers?

 

[antcollinet]

is open to some additional space, another room, kitchen, and hallway

As you point out - your room is not a simple box.

Even with a simple box resonant frequency will be impacted by the contents of the box. Your simple calculation can only ever give an indication. In the situation you describe, with an open side, then all bets are off.

 

[KSTR]

'Back of the envelope'-style calculated resonance frequencies usually assume
a) perfect shoe-box geometry
b) infinitely rigid walls
c) room completely empty
d) defined air pressure, temperature and humidity
In real life values will always be off and +-10% is nothing I would worry about. Only way to check whether the speaker itself is involved would be using different speakers, or the existing ones with ports stuffed.

 

[CapMan]

I have an interior partition wall on the right, exterior on the left - more bass suck out on the right which I am fairly certain is the partition wall taking energy out at that frequency. No way to know unless I rebuild that wall