KEF LS50 playground - measurements of raw drivers in factory cabinets and simulations

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Maty, i don't think that harshness in Q100 comes just from tweeter being 1dB louder than it should. In Q500 thread in this forum i did slight mod of its factory crossover and i think that the same approach (different values of course) would help with Q100. I had some Q100 raw driver sim files. If i find it, tank filter and 12dB/o electrically should fix the harshness. That chainsaw look over 7kHz is product of woofer cone breakup since it is 6dB/o electrically - 0.68mH if i remember correctly.
 
I found it. Here's factory crossover:

fabricka.png

And here's slightly modified:

modifikovana.png

Adding four cheap components seems to work quite well. Point of crossing over and slopes remain virtually the same. You can buy resistors say 1R, 1R5, 2R2 and 3R3. Given the tolerances in LS50 drivers i don't expect anything less in Q100. Additional benefit is that you can set the level of the tweeter per your liking.
 
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I've made some measurements of my modified Kef LS50.

Bare in mind that this is 1dB grid.

0, 10 and 20 degrees
0.10.20.png

30, 40 and 50 degrees
30.40.50.png

60, 70 and 80 degrees
60.70.80.png

Here i had to make the grid 2dB to be able to see the level of 90 degree against 0 degrees

So 0, 80 and 90 degrees
0.80.90.png

Tangerine phase plug obviously works like a charm.

I guess it is time we christen this crossover ... PSM XO :)

Enjoy and have fun
 
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Just another approach, +-1dB on axis, +-1.5dB off axis with reference to the 0.6dB/oct slope line (actually at one point it's 1.8dB), 8-9kHz midwoofer breakup >27dB below system spl. 2R, 4L, 4C. Not minimalistic, but also not very complicated. Pic1: on axis, Pic2: off axis.
 

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@Zvu

Off topic or not

I am so satisfied with the current sound of my modified KEF Q100 that I am afraid to modify the filter.

Yesterday, with acoustic instrumentation, the sound was sometimes incredible. Percussion, guitars above all.

Just now, orchestral music: Lieutenant Kijé (Prokofiev). I still marvel at how such a small speaker is capable of playing an orchestra.

The logic improves, to be in another larger room, would be two subwoofers cut at 110 Hz, I think.
 
@Zvu

Off topic or not

I am so satisfied with the current sound of my modified KEF Q100 that I am afraid to modify the filter.......

The logic improves, to be in another larger room, would be two subwoofers cut at 110 Hz, I think.

A wise man told me once - I can only show you the door. You're the one that has to walk through it.

I'd also expect improvement by correctly adding few subs, but i's also deprive the Q100 of frequencies bellow that.

And don't worry about the off topic, i don't mind :)
 
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This crossover was actually designed using XMachina software. It is shown in XSim because I usually try to modify selected results in an external (more handy) circuit editor. (This time I made only one change, 2 coils in series were replaced with a single coil with appropriate L & dcr).

That's actually pretty cool.

Is there an option in Xsim that can show Rdc of coils shown in schematic ? I'd simulate your crossover and make it a pic as i did with mine and with Goran's, if that's ok with you ?

Once again, great stuff your software is. I'll have the opportunity to try it very soon.
 
Is there an option in Xsim that can show Rdc of coils shown in schematic ? I'd simulate your crossover and make it a pic as i did with mine and with Goran's, if that's ok with you ?

No problem of course. Fell free to process or modify. And thanks for sharing the measurements!
The DCRs of the coils are on the schematic (blue labels). I've put them manually, I don’t know a way display DCRs directly but maybe it is because I'm working with an old version of XSim.
 
After the read of a lot of unanimous laudatory comments about those speakers, interested by the original design of this coaxial speaker, I decided to buy a LS50 wireless speaker set.
What was my surprise to see how the rendering of these speakers was caricatural. Fantastic trebles, awful high mediums (everything is aggressive and thin), inconsistent basses.
And this is all the more annoying as the high-end spectrum is detailed, precise, dynamic in an exceptional way.

The abrupt fractionation of the bass HP's membrane is probably responsible of this coloration that transform a piano to an harpsichord and a snare drum to a tambourin, and I do not understand why it was not filtered with steeper slopes, which should be so easy with the integrated DSP.

I'm hesitating between reselling or shelling them to add a passive plug to see if it improves things.

Another unbearable thing is that the directivity connection between the two speakers is so bad that simply changing the listening position vertically changes the tonal rendering in a huge way and that, changing the room of listen, we do not recognize the same speaker.
 
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LS50 definitely isn't a loudspeaker for everyone. No loudspeaker is. You obviously need a different set of compromises in a loudspeaker. I listened both LS50 and LS50W. Wireless is much better but it isn't worth the cash in my opinion. It is just too expensive for what it does. Even regular LS50 is too expensive.THIS loudspeaker costs 1000$/pair and LS50 is around 1500. Go figure.
 
When I first heard my KEF Q100 I was very disappointed. I thought about returning them! They sounded garish, without bass. After a very long burnin, of about two hundred hours, the sound was very different.

I think the fault is the speaker suspension, which is extremely rigid.

Frank Sinatra is playing right now and the sound is marvellous.

Frank Sinatra - September of My Years (1965), Vinyl, stereo, 2015, Universal, Holland

Now Playing + What are you listening to?
 
Stereophile and SoundStage are independent so you can trust their impedance plots.

There is no way to open LS50 without leaving a trace. There are rubber plugs, four of them, on the back. They are glued so when removing them, and you must remove them to get to the bolts that hold front baffle, they conveniently disintegrate. Plugs have printed something like -LS50 anniversary- or similar so there is no point in replacing it.

EDIT: now i see that you wrote -wireless-. Try and tell us how it went.
 
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Stereophile and SoundStage are independent so you can trust their impedance plots.
I have not fond any, only impedance curves of the complete enclosure (IE other side of the passive filter). That don't tell e lot.
EDIT: now i see that you wrote -wireless-. Try and tell us how it went.
I'm not very hot on this. So disappointed by those speakers. I hesitate between reselling or trying to voice them,
 
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