Flat Anechoic Measured Frequency Response Speakers

I think these are anechoic or simulated anechoic (time-gated spliced with close-miked) measurements, but don't know for sure. Click on "Measurements", on the right-hand side:

http://www.klein-hummel.com/klein-hummel/icm_en.nsf/root/prof-monitoring_studio-monitors_main-monitors_O500C#

Duke
dealer/manufacturer

Hesson11, that is a very eductional set of curves. Thanks for posting the link.

In the 45 to 75 degree family of curves, you see that big bump between 2 kHz and 5 kHz? Unless you listen nearfield or under quasi-anechoic conditions, that bump is probably audible - and it's right smack in the region where the ear is most senstive, according to the Fletcher-Munsen curves. This excess off-axis energy in the lower treble region is caused by the tweeter having a very wide pattern just above the crossover point, and it's there on most speakers - but you cannot predict its presence from either the on-axis anechoic curve or the "listening window" curve. Kudos to SoundStage for measuring the off-axis response out to 75 degrees.

Duke

Shadorne, I think I heard that model (or possibly a predecessor) about five years ago at CES. My impression was they would indeed play very loud. They were very detailed, but to my ears they sounded forward and a bit bright. Now they may well have been just a few knob-twiddles away from nirvana, and the waveguides around the mid and tweet do appeal to me intellectually, but going by aural memory I'd prefer any of the big ATCs.

Duke

Shadorne, I hadn't seen your post four up when I typed my reply three up. Congratulations on catching the implications and applicability of that off-axis bump. When working on a design, I place most of my attention on what's happening off-axis rather than on-axis.

Bob, no doubt much of the credit for those impressive measurements is due to a very well executed digital processing system. But signal processing cannot do much about radiation patterns, and the polar maps of those patterns are what I'd give the greatest consideration to (the green plots towards the bottom of the measurements page). You pretty much never see polar maps or any sort of off-axis data becaus it almost always sucks, and the K&H polar maps both look pretty darn good to me.

Bob, typically driver interaction has a large effect on radiation pattern in the vertical plane but not much in the horizontal plane. Even with the digital crossover, you can see the results of driver interaction in the vertical polar map.

I use a passive crossover, and my horizontal radiation patterns are as smooth if not smoother than the K&H. My vertical pattern probably isn't a good, but that's less critical (as long as the power response is smooth) because we listen within a fairly narrow vertical window anyway.

I found a website that said the big K&H speakers retail for thirty-six grand a pair, but you can mail-order them for a mere twenty grand a pair. That's actually one helluva discount.

Duke

Jkalman, in my opinion Robert E. Greene of the Absolute Sound (also a high-ranking professor of mathmatics at UCLA) has a genuine understanding of what matters when it comes to a loudspeaker's in-room performance. Here is a link to his website:

http://www.regonaudio.com/

See in particular the measurement supplements to his TAS reviews of the Gradient Revolution and Jamo 909, and the measurements of his Harbeth monitor 40 (that page is currently "under construction" but he has some measurements posted).

The "target curves" that you see in the Gradient and Jamo supplements are similar to a target curve published by Bruel & Kjaer, which I can't find online but it's basically flat below 100 Hz and then slopes down by a little less than 1 dB per octave from there on up. I presume this is a non-time-gated measurement from the listening position.

Duke