KEF Q350 Speaker Review

[amirm]

It can. Here's a screenshot of the DIS module where you can set the voltage steps and frequency range.

Not going to pay $3000+ for just that option. When I had a trial license, it would not go past 2 kHz or so. Could not figure out why. In their documentation they show full response but I could not get it there.

The option is really designed for driver testing, not full range speakers.

 

[tomtoo]

Not Harman enough?

I wouldnt say that. It's more like that even if the measurements look realy good, there is still a lot of room for subjektive impression.

 

[amirm]

Maybe if KEF get bought out by Samsung you'll like it better.

I liked Arcam less when that happened!

 

[amirm]

By the way, forgot to comment on power handling. It is quite good but then hits a ceiling with a nasty crackling sound. I am used to hearing the woofer bottom out sound. It was pretty loud though by then. And this was with one speaker playing.

 

[amirm]

Preference Rating
SCORE: 5.6
SCORE w/ sub: 7.4

I was afraid you were going to do this to me. For those of you who don't know what is going on, I share the measurements @MZKM prior to posting the review. The Son of the you know who, doesn't tell me the score until the review is finished! So in that regard, I am operating blind, albeit with having the graphs in hand.

 

[hardisj]

That is why I noted it on the graph. NFS could do it but I would not want to run it for another 2 hours just for this purpose. Stereophile has an approximation of it.

I just don't want people to draw the wrong conclusion. The point is the FR can be quite different depending on the distance of the mic from the DUT.

 

[hardisj]

Not going to pay $3000+ for just that option. When I had a trial license, it would not go past 2 kHz or so. Could not figure out why. In their documentation they show full response but I could not get it there.

The option is really designed for driver testing, not full range speakers.

Yea. It ain't cheap. DIS is great for other factors as well such as compression testing. Though, I agree the IMD portion is much more useful for raw drive units when you're trying to determine the best range for them to cover in a speaker.

Not sure how much things change when you have the NFS. I assume you are using TRF for HD and batch running separate TRF instances?

 

[Haint]

Predating any of Amirm's reviews, I used Q150's in my living room for almost 6 months and thought they were pretty good for the $299/pr sale price, but was never especially bowled over by them. My impression was also that they sounded muddy and less detailed in a direct comparison to M16's (which I significantly preferred, immediately replacing the Q's with). I'm the furthest thing from a trained or expert listener, and this all predated any of Amirm's measurements, so I wasn't listening for graph anomalies or preference scores. I'm assuming the 150's also measure very well, so I'm curious what objective data may have colored my impressions and preference to such a degree.

 

[napilopez]

Thanks!

I'd like to point out again that Amir wasn't wowed by a narrowish horizontal directivity design. As he noted in the review, but it seems to be trend. (I focus particularly on the 2-8kish region when I determine wide or narrow).

Currently, the Amir winning formula seems to be wide directivity + a bit of a bass boost (at least barring strong bass extension) and lots of power handling, assuming decent spin performance otherwise.

Maybe it's time someone starts recording Amir's reactions along with the measurements and directivity and seeing what trends emerge. You can patent is as the Amir preference score.

Note, for example, that the speaker measures quite similarly to the ELAC. That one scores a teensy bit better, but has noticeably wider horizontal directivity. Q150 was 55 degrees, the ELAC about 75/80.

Just speculating though.

Anyway, looks like a very solid speaker for the price that just wasn't for Amir. I'm going to guess those two resonances would should up in a nearfield port response. Tends to be the case for resonances around 1k in my experience. Should hopefully be EQable with a little effort.

 

[GXAlan]

I was afraid you were going to do this to me. For those of you who don't know what is going on, I share the measurements @MZKM prior to posting the review. The Son of the you know who, doesn't tell me the score until the review is finished! So in that regard, I am operating blind, albeit with having the graphs in hand.

Science doesn’t lie.
Observations, even subjective, warrant additional investigation.

The KEF Q350 is better than the XPL 90 In many regards but the XPL90 is smoother from 100 Hz to 1500Hz or so.

Might the preference score underestimate the value of smoothness in this region compared to somewhere else (say above 16 kHz)

 

[napilopez]

Science doesn’t lie.
Observations, even subjective, warrant additional investigation.

The KEF Q350 is better than the XPL 90 In many regards but the XPL90 is smoother from 100 Hz to 1500Hz or so.

Might the preference score underestimate the value of smoothness in this region compared to somewhere else (say above 16 kHz)

While I'd bet top dollar that some frequency ranges account more for preference than others - or at least we're sensitive to them in different ways - the preference score calculation only includes up to 12kHz for the NBD score, and up 16kHz for the smoothness score. As noted above, my theory Amir seems to have a decreasing preference for narrow horizontal directivity designs - which he noted explicitly in this review. The transition to yellow in the Q150 is roughly 55 degrees vs 65/70 for the XPL90.

 

[richard12511]

I was afraid you were going to do this to me. For those of you who don't know what is going on, I share the measurements @MZKM prior to posting the review. The Son of the you know who, doesn't tell me the score until the review is finished! So in that regard, I am operating blind, albeit with having the graphs in hand.

I'd say that's preferable. Knowing the score ahead of time might influence your review.

 

[oivavoi]

I'd like to point out again that Amir wasn't wowed by a narrowish directivity design. As he noted in the review, but it seems to be trend. (I focus particularly on the 2-8kish region when I determine wide or narrow).

Currently, the Amir winning formula seems to be wide directivity + a bit of a bass boost (at least barring strong bass extension) and lots of power handling, assuming decent spin performance otherwise.

Maybe it's time someone starts recording Amir's reactions along with the measurements and directivity and seeing what trends emerge. You can patent is as the Amir preference score.

Note, for example, that the speaker measures quite similarly to the ELAC. That one scores a teensy bit better, but has noticeably wider directivity.

Every time I intend to write something in these speaker threads, I come here and find out that @napilopez has already said it, just more eloquently. Couldn't agree more! I think the missing part of the preference score rating is whether directivity is wide or narrow. Our beloved host, and quite a lot of listeners, seem to like wide directivity.

 

[tecnogadget]

Pretty decent preference score for a pair of $700 stand mounts although not best in class. I wonder how the smaller Q150 would do.

And the fact they are being highly discounted by some dealers makes it even more appealing. They are as of today 498€ brand new in Spain.

 

[GXAlan]

While I'd bet top dollar that some frequency ranges account more for preference than others - or at least we're sensitive to them in different ways - the preference score calculation only includes up to 12kHz for the NBD score, and up 16kHz for the smoothness score. As noted above, my theory Amir seems to have a decreasing preference for narrow horizontal directivity designs - which he noted explicitly in this review. The transition to yellow in the Q150 is roughly 55 degrees vs 65/70 for the XPL90.

Good info on what frequency is included in the calculation.

Amir hated my JBL 4319 which also have wider horizontal dispersion than the KEF's. The JBL4319 weren't as clean as the XPL-90's in that same range (with the dip at 800Hz).

My third set of speakers that are coming to @amirm should have really wide horizontal directivity. Let's see how that scores subjectively

 

[napilopez]

Every time I intend to write something in these speaker threads, I come here and find out that @napilopez has already said it, just more eloquently. Couldn't agree more! I think the missing part of the preference score rating is whether directivity is wide or narrow. Our beloved host, and quite a lot of listeners, seem to like wide directivity.

Amir knows best of course. I'm partially projecting though because that largely reflects my feelings. The difference is when I measure/listen to narrower directivity speakers I will almost universally toe them out or use extreme toe-in to increase the loudness of sidewall reflections. Amir can't really do that with mono listening.

Would be nice to see more research on this. There's some conflicting stuff in Toole's book about it. On one hand, the preference score papers suggest directivity was not a strong factor in preference other than the best speakers had smooth directivity. On the other hand, directivity-specific studies suggest people will pick wider speakers for recreational listening.

Also, we know that the same speakers tend to win overall in both mono and stereo tests, but I wonder whether we can extrapolate that to a single listener who seems (again, this is me guessing and I could be totally wrong) to have particular directivity preferences listening to dozens or (eventually) hundreds of speakers.

 

[napilopez]

Good info on what frequency is included in the calculation.

Amir hated my JBL 4319 which also have wider horizontal dispersion than the KEF's. The JBL4319 weren't as clean as the XPL-90's in that same range (with the dip at 800Hz).

My third set of speakers that are coming to @amirm should have really wide horizontal directivity. Let's see how that scores subjectively

Looking forward to seeing the results of that third speaker!

As for the 4319, that's a good point, but again I bring up directivity. Look at how much smoother the XPL90 is in its DI curves. Also the 4319 does score worse, especially if you remove LFX from the equation.

 

[tecnogadget]

People lost their minds when the Buchardt S400 had a high-Q resonance at ~500hz and that had a Q of about 15. The first peak in the Kef Q350 is at about 700hz with the -3dB points at about 600 and 800hz. That's a Q of about 3.5. Ruh-roh. I expect no less than 15 pages of people arguing over what the culprit of this is.

The steep drop in the low bass, even though it is probably an octave lower than where most would cross it over to a subwoofer may cause some trouble unless you have in phase matching the response in the 40-50hz region. Again, depending on where you cross your subwoofer.

I'm shocked by those two resonances at 700Hz and 1.2 kHz, I was expecting more from this UniQ midrange unit given the fact they included the "rib" stamp over the driver cone, which in theory should make it more rigid and help it work in a "more pistonic" way.

It really strikes me after the great results from your Q100-LS50-R300 isolated driver measurements.

 

[Soniclife]

Bass response is stepped though, being much higher above 100 Hz.

Kef's white paper on the R series shows similar shape in the bass across the range, a deliberate adjustment for room gain?

 

[dc655321]

I'm shocked by those two resonances at 700Hz and 1.2 kHz, I was expecting more from this UniQ midrange unit given the fact they included the "rib" stamp over the driver cone, which in theory should make it more rigid and help it work in a "more pistonic" way.

May not be the driver - look at the "glitches" in the impedance plot.