BBIBH
You are absolutely correct. If you audition a pair of speakers which stand among many other speakers, even if the other speakers are not receiving signal their drivers will be excited by the sound waves produced by the speakers which are the subject of the 'demo.' Each driver, in such a listening room, will demonstrate the characteristics of a Helmholtz resonator.
Here are some frequency response plots for the Polk LSi9
Frequency response, 20Hz - 20kHz (measured @ 2m, plotted @ 1m) Loudspeaker sensitivity (averaged 300Hz - 3kHz, 2.83V/1m)
Listening Window, 20Hz - 20kHz (measured @ 2m, plotted @ 1m)
Response curve is an average of five measurements:
on-axis, 15 degrees left and right off-axis,
15 degrees up and down off-axis
Here are the frequency response plots for the M22
Listening Window, 20Hz - 20kHz (measured @ 2m, plotted @ 1m)
Response curve is an average of five measurements:
on-axis, 15 degrees left and right off-axis,
15 degrees up and down off-axis
We can see that both speakers test excellently - the Polks are slightly bumped up in the upper bass region. The Axioms demonstrate remarkably flat response curves.
Where it gets a bit more interesting is if we look at the efficiencies of these speakers (not sensitivity, they both test about the same at 87.5 db.)
The impedance/frequency plot of the Polks show they're a load to drive.
Here's the impedance/frequency plot for the M22s
I'd say the Polks are a more demanding load for an amp, especially a low powered tube amp, than the Axioms because the Polks appear to hit the 2 ohm level and make 4 ohm demands for much of the lower and mid frequencies.
The M22s present as a very easy load except at about 4KHz.
BTW, thanks to SoundStage for their graphs and measurements!
Isn't it interesting how well the Axiom M22s compare to the $1,300 (MSRP) a pair Polk LSi9's?
