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Neumann KH 80 DSP Monitor Review

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All reflections are filtered before calculating Listening window.
It’s pretty consistent from the graphs, so maybe the system is not filtering these reflections entirely? They’re happening at 8kHz-10kHz, that’s 3-4cm distance from the tweeter. Stuff like that shows up when the faceplate of the tweeter is not perfectly flush with the baffle. But here it shows up with very smooth waveguides as are on Neumann and Samsung 305P. Does the Klippel mic get that close?
 

ctrl

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I mean something causes an "comb filter like effect" by interference - e.g. by reflection.
All reflections are filtered before calculating Listening window.
Room reflections are "filtered out" by using a gate. If the mic or measuring gear itself causes reflections you need some sort of "calibration file" for each position of the gear.
 

Krunok

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It’s pretty consistent from the graphs, so maybe the system is not filtering these reflections entirely?
If that would be the case all measurements so far would be totally wrong and certainly not similar to the measurements of that reference JBL that was sent to calibrate the NFS.

Guys, proposal to repeat the measurement at a reference axis specified by the manufacturer and at a lower level to avoid LF compression is one thing but these conspiracy theories of yours are totally different thing and are completely off.
 
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edechamps

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Guys, proposal to repeat the measurement at a reference axis specified by the manufacturer and at a lower level to avoid LF comrepssion is one thing but these conspiracy theories of yours are totally different thing and are completely off.
Agreed. Small high-Q ripples in the treble are benign; they are unlikely to be audible and could be anything from sample-to-sample variation to small differences in the measurement process. (Personally my money is on reflections off the NFS arm and microphone.) That's very different from the broad tilts in the bass and treble, which are way more audible and cannot be explained that easily.
 
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I really don't care for now as speakers measurement is a much different beast from electronics measurements and I think we are in a kind of beta test for now, but if you put the speakers on a desk and if they have a freaking switch that you are instructed by the manufacturer to use when you put them on a desk I think you should measure them that way. In addition measurement wise the neumann measure better compared to JBL (and are very very very small too!).

Anyways the JBL are going back and I have a pair of Genelec incoming.
What Genelecs are you getting? I have been using 8020c for the last 4 years and really like them for nearfield listening. I would like to upgrade but dont know what to get.
 

Thomas_A

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The system works, there are just small things to think about such as SPL limits for small speakers. Let Amirn do his tests and find out.
 
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Very good suggestions, I haven't listened to the 8331A but if I could afford them they would probably be my first choice.
 

BYRTT

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Thanks BYRTT!

So, this really bothers no one? Every measurement shows comb filtering in the same frequency area - what are the chances?
Welcome, not i'm specialist but think we should relax maybe NFS is monster of precision instrument so they can open up a higher resolution with less smoothing/interpolation than we usual see and what scare some here, will imagine omni microphones in a diffuse field catch a havoc of information as can be seen with too long a window and filter less measurement, look all the grass below in a 500mS window, second one is 1/6 FDW and IR/SR stays always the same, debate is probably fine and informative for us but think we should give it time, think so far analyze quality looks be high and hopefully also precise.

Difuse_field_1.png


Difuse_field_2.png


Difuse_field_3.png
 
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Thomas savage

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These threads have always been a chance to ' review ' the data provided. Peer review if you like .

A separate thread addressing communalities of concern from multiple speaker reviews wrt Amirm's measurement setup would be nice.

Folks here don't like creating new threads , I ask and they ' like ' the request but just ignore it. They also ignore my request to provide post numbers so I can transfer content and create a new thread for new branches of discussion.

So I give up . I'm not going through hundreds of posts reading them all and trying to work out what thread to put them in. Take some responsibility for yourselves please! Create new bloody threads and if you make a mess in a thread give me the post numbers so I can create a appropriate place posthumously.

Examining data like this will never produce a choir of approval, it's a bit of a ball buster for @amirm.

Suck it up champ , everyone is valuing what your doing. We just need to build a form of consensus and shared understanding before we gallop off with loads more speaker reviews.

Short term pain long term gain imo .

If you want blind approval there's always your dog's ha ha
 
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These reflections are happening at a distance of 4cm. These are not room reflections. Maybe top of the cabinet, area where the the tweeter transitions to woofer, mic, mic boom, etc.
 
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Juhazi

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Thanks BYRTT!

So, this really bothers no one? Every measurement shows comb filtering in the same frequency area - what are the chances?
View attachment 47232
Well, don't all these speakers have a waveguide for the tweeter? Here we can see how well each manufacturer has taken control of the cavity effect of the waveguide/horn. Kali IN-8 has deepest wg and because it's coaxial, there are also more wiggles caused by discontinuities in the throat (junction of tweeter and mid). Most waveguides show smoothest response 10-15deg off-axis and IN-8 is smooth then, and it's listening window response is smooth too!



More about this in these links
http://techtalk.parts-express.com/f...-axis-response-of-various-tweeters-waveguides
https://pdfs.semanticscholar.org/a1af/8f8fc0c22a31a9d46efb360737de993ecab2.pdf
https://jblpro.com/innovation-directivity

dxt proto gain.jpg
 
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Juhazi

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Does this mean that listening window curve contains reflections above 1kHz or that above 1kHz time windowing is used to eliminate reflections?
I have understood that the NFS system checks each of the about 300 measurements individually, and by some algorithm decides when short gating (like 4ms) is enough and when its starts doing that fancy Field Separation of reflections. That's why in the picture transition zone is 500-1000Hz.

At least NFS should handle each measurement individually, because each mic location has different reflections from boundaries!
 
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