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KEF Q100 Speaker Review

Poseidons Voice

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It’s interesting but per Amir’s first post on this thread, the speaker comes with a port plug and apparently GR feels this is the right way to go as well (it’s unclear if Danny knew that a port plug comes with the speaker). But honestly, I would be interested to see this modified Q100 remeasured by Amir and to see if Amir hears any audible improvements.

Best,
Anand.
 
D

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It’s interesting but per Amir’s first post on this thread, the speaker comes with a port plug and apparently GR feels this is the right way to go as well (it’s unclear if Danny knew that a port plug comes with the speaker). But honestly, I would be interested to see this modified Q100 remeasured by Amir and to see if Amir hears any audible improvements.

Best,
Anand.
I'm sure the Danny version would sound better and measure better. The issue here is the cost/inconvenience of it.
I'm pretty familiar with the Q100 speakers. 'Have had a pair for many years and I modified the crossover a long time ago.
They do clearly sound better with the supplied port plugs installed.

Dave.
 

aarons915

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I'm sure the Danny version would sound better and measure better. The issue here is the cost/inconvenience of it.
I'm pretty familiar with the Q100 speakers. 'Have had a pair for many years and I modified the crossover a long time ago.
They do clearly sound better with the supplied port plugs installed.

Dave.

Port plugs are really only good to help them blend with a sub, I can't imagine many people would prefer a speaker with less bass. The only exception would be if you have a large bass peak that is attenuated by plugging the port but the better option is just EQ'ing that peak.
 
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Port plugs are really only good to help them blend with a sub, I can't imagine many people would prefer a speaker with less bass. The only exception would be if you have a large bass peak that is attenuated by plugging the port but the better option is just EQ'ing that peak.
No, there is some viable usage even if no subwoofer is mated. But that depends upon the application the speakers are used in.
The roll-off characteristic is smoothed/changed and there's actually a bit more bass lower in the frequency range. And that's before any closed-box EQ might be applied.
And, in this case, as a side feature, it appears to solve the "port resonance" issue.

Dave.
 

aarons915

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No, there is some viable usage even if no subwoofer is mated. But that depends upon the application the speakers are used in.
The roll-off characteristic is smoothed/changed and there's actually a bit more bass lower in the frequency range. And that's before any closed-box EQ might be applied.
And, in this case, as a side feature, it appears to solve the "port resonance" issue.

Dave.

I actually experimented with the Q150 awhile back and measured Open ports, partial sealed and sealed parts and got this.
Q150 port plugs.jpg


You're giving up a lot of output where it matters by sealing the speakers in my opinion. I personally prefer running the Q150 and LS50 with the ports open and 4th order slopes to blend to a sub, they sound much better not trying to reproduce deep bass and it takes care of any port resonance also.
 

wowo101

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'Have had a pair for many years and I modified the crossover a long time ago.

Can you share a bit of info on your modification? Would love to compare the different options popping up here before having a stab at modifying my pair of Q100s...
 

QMuse

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I actually experimented with the Q150 awhile back and measured Open ports, partial sealed and sealed parts and got this. View attachment 54777

You're giving up a lot of output where it matters by sealing the speakers in my opinion. I personally prefer running the Q150 and LS50 with the ports open and 4th order slopes to blend to a sub, they sound much better not trying to reproduce deep bass and it takes care of any port resonance also.

If you set XO point to 80-90Hz and high-pass Q150/LS50 with 4th order slope it really doesn't matter if you keep the port open or seal it. In fact, you would do better to seal it to get rid of port resonance and turn them into sealed boxes as low bass will be played by SW(s).
 

maty

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KEF Q100 with the mods of GR-Research, aka Danny Richie. Port closed.

Resized and optimized, from the YouTube Lets fix the Kef Q100!

Frequency and crossover

KEF-Q100-GR-Research-frequency-crossover-by-Danny-Richie.png



Impedance

KEF-Q100-GR-Research-impedance-by-Danny-Richie.png



Spinorama Horizontal

KEF-Q100-GR-Research-spinorama-by-Danny-Richie.png



Cumulative Spectral Decay (CSD)

KEF-Q100-GR-Research-CSD-by-Danny-Richie.png
 
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maty

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Original, measured by Zvu, at 30º-40º-50º

index.php


Spinorama Horizontal of Danny Richie mod

index.php



It would also have to touch up with minimum phase PEQ.
 
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Poseidons Voice

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Maty,

Those are NOT Spinoramas. Those are horizontal off axis curves that are gated measurements with smoothing such that they are only somewhat relevant at 1khz and above (Frequency resolution of Danny’s measurements is 250Hz, Amir’s is < 1Hz). So especially below 1khz his measurements start becoming highly irrelevant.

Please correct it.

Spinoramas are NOT easy to obtain and are very expensive & time consuming to boot.

Best,
Anand.
 
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maty

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My fault, you are right. Corrected. Thank you.
 

maty

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I suppose it has been noted how the boxes rumble when knocked with the knuckles. The improvement that I noticed after adding mass + damping was substantial. It is something that cannot be solved with equalization or a new crossover.
 

maty

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The conclusion is clear: the 5.25" Uni-Q coaxial driver is excellent. KEF has saved on everything else.

The logical thing, to me, would be to buy the substitutes, KEF Q150 (now at $ 300 again in NA) and improve them. The frequency response on the axis is already very good, so all you have to do is improve the quality of the crossover components and everything else -> much less money to spend.

With the rear port closed and one or better two subwoofers we would have a good equipment to listen up to 2.5 - 3m away from the speakers or a little more thanks to the sub(s). Then a few gentle tweaks to the frequency response at the listening point and enjoy!

Of course, much better on supports.
 
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Can you share a bit of info on your modification? Would love to compare the different options popping up here before having a stab at modifying my pair of Q100s...
It was an active crossover.......as usual with many of my speaker modifications.
I see little point in spending a good chunk of money on passive "high-quality" audiophile components when you can spend the same, or a bit more to take an existing speaker as far as it will go....with a line-level scheme.

Dave.
 
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maty

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Being a simple filter the cost of the improvement is affordable, something that I do not think happens with JBL Studio 530 having too many components. To improve the frequency response -> a good soft player with minimum phase PEQ + rePhase.

Active but the box need more mass+damping yes or yes. What did you do about it?

With miniDSP?
 
D

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I actually experimented with the Q150 awhile back and measured Open ports, partial sealed and sealed parts and got this. View attachment 54777

You're giving up a lot of output where it matters by sealing the speakers in my opinion. I personally prefer running the Q150 and LS50 with the ports open and 4th order slopes to blend to a sub, they sound much better not trying to reproduce deep bass and it takes care of any port resonance also.
You need to make a close-up measurement to properly characterize the difference. You have room effects contributing.
That said, when you plug the port of a typical vented-box speaker the box is now too big and you'll get a low-Q response. (Thus, my comment about equalizing.)
The bass response (in any configuration) is certainly the weak-link in the Q100 system.....if asked to operate full range. Without augmentation, I consider them more like computer speakers. Which is how I used them. :)

Dave.
 

aarons915

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If you set XO point to 80-90Hz and high-pass Q150/LS50 with 4th order slope it really doesn't matter if you keep the port open or seal it. In fact, you would do better to seal it to get rid of port resonance and turn them into sealed boxes as low bass will be played by SW(s).

I've tried both ways but you can't seal the port and use a 4th order high pass or the bass will roll off way too fast and not blend very well. With a sealed port I use a 2nd order high pass to complete the 4th order slope, this is the best option for most people who use receivers with the typical 2nd order high pass and 4th order low pass. I personally prefer to keep the ports open and use a 4th order high pass to take advantage of the low distortion bass above port tuning, it sounds a bit more open to me that way.
 

QMuse

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I've tried both ways but you can't seal the port and use a 4th order high pass or the bass will roll off way too fast and not blend very well. With a sealed port I use a 2nd order high pass to complete the 4th order slope, this is the best option for most people who use receivers with the typical 2nd order high pass and 4th order low pass. I personally prefer to keep the ports open and use a 4th order high pass to take advantage of the low distortion bass above port tuning, it sounds a bit more open to me that way.

You don't need to have same slope on the sub side and on the mains side. Sealed boxes generally sound better except they require larger volume to produce deep bass. if you handed over bass duties to sub no need to have port open anymore.

Are you using high pass for your mains or not?
 

aarons915

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You don't need to have same slope on the sub side and on the mains side. Sealed boxes generally sound better except they require larger volume to produce deep bass. if you handed over bass duties to sub no need to have port open anymore.

Are you using high pass for your mains or not?

You don't need to, but it's optimal if you want your subs and mains to blend properly. Of course everyone should try it both ways and do what sounds best to them, as mentioned I've done this and prefer to keep the ports open, YMMV.

Yes I mentioned twice now I use a 4th order high pass on the mains, with open ports.
 
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