...
Here is a link to another analysis of the IN-8 where the reviewer did his own measurements:
http://www.hifi-forum.de/index.php?action=browseT&forum_id=30&thread=13717&postID=33159#33159
His comments are in German, but you can see the overall frequency response of the speakers. Minus the bumps below 200 HZ, which I write off to the room, these measurements reflect what we would expect as far as the performance of the loudspeaker.
...
Hello everyone,
Since I am the guy who did those measurements and review (I bought my pair myself as I like to collect neutral, good measuring speakers and Genelec 83x1 are too expensive for my current listening situation), I would like to give some comments, but first of all thank Amir for this excellent platform (which I knew since some time due to his great electronics measurements) and his huge step to get himself a so expensive Klippel NFS system from my country.
As I wrote in my German text/review (best translator for English to German is imho
https://www.deepl.com/translate ) my measurements of course are by far not as accurate as the ones here, since I just use the common windowing or spacial averaging methods in my unfortunately not big listening room.
Before I did my measurements, I listened to the Kali pair for a week, so my listening impressions are not biased by them. The only small problems I heard then were that metallic cymbals were too polite and also few common room modes.
The cymbal problem was confirmed later in my measurements and now also on Amirs and is common to most coaxial drivers with very few exceptions like KEF which optimises they coaxial drivers since more than 20 years. Most coaxial drivers show some problems on axis (which multiply due to the coaxial symmetry) but disappear on other angles, so correcting them on axis would deteriorate the off axis and even worse the power response of the speaker, so an experienced engineer like Charles Sprinkle correctly didn't do so. One thing that could have been done though is to recommend in their user manual not to tow them exactly in to the listeners position, but more or less, which I also did in my later listening tests.
The other main complaint of Amir is actually an approximately a 3dB too silent woofer, since the official crossover frequency is at 330 Hz and thus quite at the frequency where the drop/step in his measurements happen. This one is questioned by Kali in their post this morning and I can't comment it from measurements point of view due to my windowing technique. What I can comment though is its relatively low relevance in typical listening rooms and loudspeaker placements, as due to nearby boundary surfaces and room modes there are always discrete peaks and dips below
the Schröder frequency of the room which need equalising. On the other side, in my room setup as well of some friends of mine where I took some measurements too, loudspeakers with deep linear bass usually have a bit too much lower bass, even compared to the Harman target curve with the low bass bump, but that can be different for example in rooms with non-solid walls.
I can post a moving microphone measurement around my listening position in my relatively new, unfortunately not yet acoustically optimised, listening room compared to my preferred Harman target curve when I don't toe them fully in:
As it can be seen, almost no EQ is needed above 500 Hz, which is often an indication of a good loudspeaker, a louder woofer would actually mean rather more correction necessary in my setup, only the bit too tame higher treble could need a couple of dB, here my current equalised response:
As it can be seen except the slight high shelve filter there are only 2 tiny filters above 500 Hz which are also more for my conscience and the listening difference without them is very small and actually without them the sound is a bit more pleasing due to the small presence dip.
With all this I am trying to say that precision measurements of loudspeakers, like they are now performed on this platform, are extremely welcome, but also need upmost care in their interpretation (not different to their audio electronics counterparts), one simple metric like SINAD is too nice to be alone fully informative, especially with loudspeakers, because I already saw few people writing the JBL 305 is much better. Well, I own the 305 MKI (which is very similar to the measured MKII) since it was released and can assure you, that is not true in most cases, maybe only at extreme nearfield listening distance and if not using EQ. We cannot ignore audible intermodulation distortion in the psychoacoustically critical mid regions when things get louder on a small two way speaker and/or more bass-heavy, also the more continuous power response and vertical radiation pattern of a coaxial driver. Also we shouldn't forget that as Dr. Floyd Toole says, anomalies in the frequency response can be easily corrected by EQ but not anomalies in the radiation pattern, a reason why I also have kept my passive KEF LS50 since they were released (now as my desktop speakers), because they are really great with just a bit of EQ which corrects their FR anomalies.
Best regards
Thewas, who loves and owns many models of loudspeaker brands with serious engineering like also Genelec, JBL, KEF etc.
