KEF LS50

[jerryo]

I have just quickly read the white paper regarding the design of the LS50. It seems to me, that anyone who is interested in the development of drive units and enclosures should read it as well and then to go and take a listen to the speakers before dismissing them. I am actually really looking forward to hearing them. Not just the LS50 but the R100/300 etc range as well.

[Joe Roberts]

I suspect one reason Joe Roberts, given his general equipment/loudspeaker preferences, may have liked them is that they seem to be voiced voiced to add some emphasis to the midrange.

I'm glad you somehow know what I like because I am only starting to figure it out myself. I am fairly sure that the dream I am chasing is not at all the sound you are imagining me to insist on.

That being said, I did not find the LS 50 to be at all "midrange-heavy" in the fat and slow sense. If anything I felt a subjective awareness of the 3-5k presence range giving the speaker a rather lively character with a potent sense of clarity. Decent bass extension and articulation also.

The speaker had what I would consider a monitor-appropriate tonal balance. Definitely not juiced up in the upper bass/lower mids. I try to avoid the term but this is a sonic character that many would consider "neutral."

I must caution against reading too much into the written word. I read a lot of the available literature on the LS50 in the last weeks, given that I have been telling people about them in various forums. I would say that reading the reviews and lit are very interesting follow-ups to my experience of hearing the LS50, but I would have NO IDEA how they actually sound from the literary experiences or the published graphs.

I say think "big, open, clear, detailed sound" and that starts channeling expectations in the proper direction. The thing that stuck me and caught my attention is the scale of the portrayal. They put out a huge 3-D soundscape that drew me in from 50 feet away.

I have no idea what sort of electronics were in use in this demo, certainly not the kind of thing I would be using at home, but the overall presentation was very effective.

[Pallas]

Originally Posted by Joe Roberts

I'm glad you somehow know what I like because I am only starting to figure it out myself. I am fairly sure that the dream I am chasing is not at all the sound you are imagining me to insist on.

I'm not really interested in discussing this further with you, because honestly I'm not sure we have anything to teach one another. I suspect Mr. Oclee Brown, if he's interested, might have quite a bit to offer all of us, though.

But in a nutshell, here's what you like: antique (antiquated is the term I'd prefer to use, but perhaps that's a bit incendiary) amps with high output impedance and high distortion, driving big horns that don't really do bass or treble, but have big dynamics. Probably driven by a source that normal people put away ca. 1955. No doubt some buffoonery with magic wires, too.

Sorry man, but it's not that hard to figure your preferences out. And having seen HFN&RR's measurements of the LS50, it's not exactly a leap to predict someone with your sonic tastes would like them.

[Joe Roberts]

antique (antiquated is the term I'd prefer to use, but perhaps that's a bit incendiary) amps with high output impedance and high distortion, driving big horns that don't really do bass or treble, but have big dynamics. Probably driven by a source that normal people put away ca. 1955. No doubt some buffoonery with magic wires, too.

Actually, I liked that LS50 sound quite a bit and it is not far from where I'm trying to get to, but how can you know what that is if you have not heard the KEFs?

The point I'm trying to make is that they are surprising and distinctive in presentation, quite apart from the general run of "mini-monitors"--I heard at least twenty similarly sized speakers in Munich, snoozers all except the LS50.

You won't get that knowledge from the HFNRR article. That is like shopping for a wife from a catalog.

And I'll have you know I'm using Chinese zip cord from Best Buy at the moment.

[studiotech]

Originally Posted by jerryo

Yeah, you're right. Just one on offer, not a pair. Shame. I wonder how AJ is getting his? Direct from KEF I guess.

AJ lives in Tampa. Pretty sure he is NOT direct with KEF. They liked his design but do not provide him with the drivers.

[Joe Roberts]

@ Pallas:

One other point....it is a bit insulting to creative and motivated speaker people such as the good folks from KEF to think you can read a review, look at at FR plot, and know what their creation sounds like.

The HFN&RR reviewer, like me, said he was "shocked" by the sound of the LS50.

Give the designers some credit and imagine a world where a FR plot will not tell you everything about the universe.

[jerryo]

I'm with Joe on his last point; they (KEF) have got some extremely sophisticated measuring and analysis tools at their disposal and the time and money to use them to what ever they want. In this case, the creation of a new series of drivers and enclosures that offer a step up in performance in certain specific areas. The engineers at KEF, I would imagine, are very intelligent people who take pride in their work and most probably have an earnest desire to bring to market something that they will be proud of.

Is there anyone from KEF reading this Thread I wonder. I doubt it, but it would be good to hear from them directly..

[Melo theory]

Are we trying to learn something about this speaker?
This is DIY audio.

[jerryo]

Yes, we are trying to find out about the correlation between the driver/enclosure design and the reported characteristics of the speaker. In this way, at some point in the future DIY'ers might be able to emulate the design and maybe even improve the design to their own tastes if the specific drivers are made available.
If not this, then I do not know what you mean.

[jackocleebrown]

Hi Pallas,

The drivers from the Q series, R series and LS50 all share a common lineage. The Q were the first to be developed in around 2010 as a concerted effort to get some of the features of the Concept Blade drivers into affordable loudspeakers. Over the years following the launch of the current Q range we have refined and tweaked the drivers resulting in those used in the R and LS50 drivers.

A quick summary:

There are 5.25, 6.5 and 8inch Uni-Q driver in the Q range. This discussion is focused on the 5.25inch which is used on the Q100 and Q500.

The driver in the R100 is based on the Q100 driver but has a different cone (which you can identify the driver by from the font) and some tweaks to the tweeter and midrange magnet systems to reduce the distortion (addition of shorting rings and a copper cap).

The LS50 driver is a special edition of the R100 driver with a different voice coil spec (to give a slightly different bass response in the system). The surround is also different and gives a slightly tidier upper MF response. We slightly adjusted the geometry around the tweeter magnet OD, also to improve the MF response.

All the best, Jack.

Originally Posted by Pallas

As has been stated several times in this thread, it's the driver from the Q100. The Q700 uses a larger midwoofer.

It is more likely than not also the Q500 (5.25" tower), but there's only one person who has posted on this thread who would know that for sure (Mr. Oclee Brown).