Quote Originally Posted by SunByrne View Post
the results for the S2-EX are quite compelling, particularly the horizontal dispersion—not that great horizontal dispersion is a surprise. In-room response overall outstandingly smooth, too, and great impedance results.

Also as expected, slight bowing upward of the in-room means they'll sound just a teensy touch bright to some, which I'm sure the ASR guy will say makes them terrible.

Yes, the horizontal dispersion is remarkable as to how wide and linear it remains, with no narrowing. It clearly shows just how well the RAAL ribbon blends with our EX woofer.


Those who think they can judge the “brightness” of one speaker compared to another that have dramatically differing radiation patterns by simply viewing the estimated in-room response graph would be in for a surprise if they actually spent the time to listen. We have never had a single Sierra-2EX customer comment that the speaker sounds bright, most comment that is on the warm detailed side.


I have done extensive comparisons with the 2EX compared to the Revel M106, most have found the M106 to sound brighter in comparison (including myself) This could also be due to the fact that the 2EX has considerably deeper bass extension and also more midbass so more research needs to be done on my part, but this is something I am heavily vested in.


The calculation determining EIR is heavily weighted towards the horizontal response of the speaker. With such wide horizontal dispersion, EIR will always appear to be tilted up a bit in the high frequency range (keep in mind that woofer dispersion is horizontally and vertically symmetrical)


Since vertical dispersion of the ribbon is more limited compared to a dome, the total energy released into the room is actually a bit less which isn’t represented in the EIR due to the weighting I mentioned above.


EIR works well when comparing two speakers with similar radiation patterns (for example, dome speaker vs dome speaker) but things get thrown off when we introduce a tweeter with dramatically different radiation.


It is also important to keep in mind that CEA-2034 is based on technology and research that occurred in the 80’s. It looks at only 2-axis (+/- 180 degs vertically and +/- 180 degs horizontally). Sound produced by a speaker is 3 dimensional, not 2. For example, we also hear the energy produced at every possible angle from the speaker (for example, 30 degrees vertically and 30 degrees horizontally). This energy is not measured in the CEA-2034 standards because, to be honest, it was a practical impossibility back then to measure it. We placed a speaker on a turntable vertically, rotated the speaker 360 degrees and recorded measurements at every 10 degs. We then positioned the speaker horizontally and did the same.

The NFS changes all of this as it moves the mic around the speaker in a sphere (two 3 dimensional cylinders actually) and we are able to see a much truer picture of the actual energy produced.

I have a hunch that at some point, CEA-2034 standards will be updated to reflect this new technology and thus provide a truer visualization as to correlating what we hear with what can be measured.