KEF Speakers

[canelli]

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jcunwired,

I have the R300s roughly 7 feet up on a wall and mounted via a pair of Pinpoint AM-40. The R300s are rear ported, but I have not had a bass issue with the speakers tilted as far forward/down as possible.

I inverted the speaker to get the uni-drivers closer to my ears, and I thought it made a huge improvement in sound quality. Amazing how a foot can make such a large difference in sound.

To keep the speaker from tipping forward and/or sliding out of the mount, I utilized zip ties thru the secondary speaker plugs to make things more secure. I anchored a small hook into the support beam and attached the ties to the hook. The hook and zip ties don't handle more than a few pounds of load so they can be very small and are not noticeable unless you get right up to the speaker. I am 6'2" and I have to stand on a chair and look behind the speaker to see the ties.

On a side note: I would not use the AM-40 tilted forward with a decent sized speaker. The reason I secured everything is due to finding one speaker on the edge of falling after installing it a few hours earlier. The 50lb load limit might be possible if you add something to help secure the speaker from sliding.

The only issue I have had with the inverted R300s is that my wife asked if I could rotate the KEF emblem so it's not upside down.

 

[jcunwired]

LOL! Leave it to our wives to pick out the most miniscule fault in our mad plans. I hadn't thought of inverting the speakers, but my room is so wide and deep that it probably makes little difference.

I did the same with zip ties. The Q300 have wall mount brackets already on the back of the speaker, I put two large staples in the wall behind each and secured them with the biggest zip tie I could find.

Thanks for the reply.

Steve, thanks to you as well, the Kef info you posted is great.

 

[AcuDefTechGuy]

A little bit of information (specifically a small batch of measurements on all of the speakers) for those interested in the Q series:
http://www.audiocinema-art.hr/UserFiles/File/recenzije/Stereoplay_02_11_Kef_Q_E.pdf

The Q-series measurements look great. John Atkinson should learn to measure them like that for Stereophile.

 

[monkish54]

The Q-series measurements look great. John Atkinson should learn to measure them like that for Stereophile.

As most know, i'm not a fan of JA or stereophile, but John's measurments are better. He is able to show the individual driver response which is very helpful and important, he shows cabinet vibration, and his polar plot looks better. His FR could use some work. He measures in such a way, and uses a certain scale that even the most neutral speaker has huge peaks or dips. It's less than forunate.

 

[Steve81]

The Q-series measurements look great.

They sound quite good too (at least IMO). The ultimate arbiter of sound quality, my son enjoys dancing to music played through the Q700s...and I'm usually there to join him

 

[monkish54]

I want a pair of the R900s...

I also want the AuraSound NRT patent to expire! Have you seen their motor structure? :O I cannot wait for the influx of NRT motors that will result from the expiration!

 

[Steve81]

I also want the AuraSound NRT patent to expire! Have you seen their motor structure? :O I cannot wait for the influx of NRT motors that will result from the expiration!

Not familiar with that, but I'll have to give the white paper a look. Just gave it a quick skim and the promises are exciting if nothing else. Reminds me a bit of XBL2 in that regard.

 

[Dennis Murphy]

I certainly agree that John's measurements are more useful, but I'm not sure I understand your comment about the "certain scale" used. It looks like the standard 5 db demarcation to me. Some of the plots look good, others are pretty problematic in the critical 1 kHz region.

 

[Steve81]

He is able to show the individual driver response which is very helpful and important, he shows cabinet vibration, and his polar plot looks better.

I'd actually be curious to know how the 6.5" and 5.25" Uni-Q drivers perform in terms of break up versus their larger 8" sibling.

 

[monkish54]

I'd actually be curious to know how the 6.5" and 5.25" Uni-Q drivers perform in terms of break up versus their larger 8" sibling.

Quite a bit better, I imagine!

Look at the difference between the Seas 6" and 8.5" Seas:

The Q900 is crossed at 1.8khz while the Q500 is crossed at 2.5khz. The Q500's breakup should be low enough, even with KEF's pretend XO.

I certainly agree that John's measurements are more useful, but I'm not sure I understand your comment about the "certain scale" used. It looks like the standard 5 db demaration to me. Some of the plots look good, others are pretty problematic in the critical 1 kHz region.

I blundered. I thought he used 10db deviations. My bad. I prefer 1db deviations.

 

[Steve81]

For those that might be interested, here is a quick on axis FR sweep of the Q700, taken at 1m, in room, 1/12th octave smoothing.

 

[Steve81]

A little more time on my hands tonight, so I took a couple more measurements, this time on the other speaker of the pair:

On Axis, 1m, 1/12 octave smoothing:

90 degrees off axis, 1m, 1/12th octave smoothing:

Again, just pure direct mode, so no help (or harm) from Audyssey.

 

[AcuDefTechGuy]

What does it look like non-smoothed?

 

[Steve81]

What does it look like non-smoothed?

Less smooth?

 

[cpp]

I picked up some Kef's K140's ( early 1990 Kef's and notes made in UK) at a local pawn shop yesterday for $75.00. Brought them home hooked them up, nice sound...

 

[AcuDefTechGuy]

Less smooth?

Doh!

I just wanted to see raw data for a change. Everyone uses smoothing.

But it's better than nothing.

 

[monkish54]

Doh!

I just wanted to see raw data for a change. Everyone uses smoothing.

But it's better than nothing.

Unsmoothed can get a bit crazy. 1/12 is generally a good enough resolution. I use 1/24 most of the time.

One of these days I'll measure my BS-22 and post 1/24, 1/12 and 1/3 for yah!

 

[Steve81]

I just wanted to see raw data for a change. Everyone uses smoothing.

Here you go

On axis, 1 foot, unsmoothed

 

[AcuDefTechGuy]

Here you go

On axis, 1 foot, unsmoothed

The non-smoothed graph looks better than the smoothed?

 

[Steve81]

Then non-smoothed graph looks better than the smoothed?

Yay for close miking