The KEF LS50 and tubes WOW WOW WOW!
- Thread starter Andre Marc
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How small? From my experience, for HT, you really need efficient, easy to drive speakers.
I made the mistake (what was I thinking!) of trying to use Spendors all around in a 5.1 system, with a PSB sub.
It was a disaster. I went to the Paradigm Monitor series (94 db eff.) all the way around and it was the best thing I did. I barely
tax my Marantz 140 wpc MM amp now.
Of course, YMMV if it is a really small set up.
garylkoh
WBF Technical Expert (Speakers & Audio Equipment)
How small? From my experience, for HT, you really need efficient, easy to drive speakers.
I made the mistake (what was I thinking!) of trying to use Spendors all around in a 5.1 system, with a PSB sub.
It was a disaster. I went to the Paradigm Monitor series (94 db eff.) all the way around and it was the best thing I did. I barely
tax my Marantz 140 wpc MM amp now.
Of course, YMMV if it is a really small set up.
Yes - I agree. Most receivers have really small power supplies when you consider that they have so many channels driven. So, even the most "high power" ones will be taxed with small loudspeakers. In general, I would argue that the smaller the loudspeaker the less EFFICIENT they are. Different measure from "sensitivity".
Hence, higher powered amplifier needed to achieve the intelligibility of speech when used with a smaller center channel.
How small? From my experience, for HT, you really need efficient, easy to drive speakers.
I made the mistake (what was I thinking!) of trying to use Spendors all around in a 5.1 system, with a PSB sub.
It was a disaster. I went to the Paradigm Monitor series (94 db eff.) all the way around and it was the best thing I did. I barely
tax my Marantz 140 wpc MM amp now.
Of course, YMMV if it is a really small set up.
The room is only 10x11
Gary, you nailed it. Trying to watch a movie and not being able to hear the dialogue, and having the volume dangerously
near full throttle is not good for the speakers, the amp, or the listener.
Took mine to a friends today. I can report that they sound really really good with Nottingham Nalagoue Dais, Manley Shrimp, Chinook, and Snapper. Besides the missing bottom end only the very highest treble has a slight sheen that allows you to tell it appart from the best silk domes. Compared to the Bösendorfer VC-1 that my friend normally plays the ls50 provides more spatial resolution resulting in a wider and possibly more transparent soundstage. The VC-1 on the other hand provides a rich bottom end and provides a fleshier presentation overall - no sheen in the treble either.
But hey, the VC-1 cost at least five times the price making the ls50 an unbeatable bargain.
But hey, the VC-1 cost at least five times the price making the ls50 an unbeatable bargain.
Wow, great post. Can you tell us the size of the room? I LOVE the Manley Snappers. Great, great amps.
No sub I presume? Can you also elaborate on what you felt were the LF limitations?
I don't know the exact dimensions of the room, but I'll wager a guess. The height is between 2.5 and 2.75m, the width is between 3 and 3.5m. The length is between 5 and 5.5m. The speakers were playing along the width, not the length. The apartment is placed in a house shaped like a horseshoe and the room therefore becomes gradually wider along the length.
Where the bass of the (not very large) Bösendorfers can become almost overwhelming in this room, that of the ls50 certainly cannot. IT is not a huge problem and it gives a lot more space to the vocals, which is a strongpoint of the ls50. Listening to jazz (as we mostly did) it was only a problem when the floor-bass was playing - here we definately only heard overtones making the strings sound a bit like rubberbands.
EDIT: No sub. The ls50 is so well integrated throughout the tonal spectrum that I somehow feel that a sub would be a mistake - it woudl simply be too hard to integrate without an obvious disparity at the tonal intersection.
Where the bass of the (not very large) Bösendorfers can become almost overwhelming in this room, that of the ls50 certainly cannot. IT is not a huge problem and it gives a lot more space to the vocals, which is a strongpoint of the ls50. Listening to jazz (as we mostly did) it was only a problem when the floor-bass was playing - here we definately only heard overtones making the strings sound a bit like rubberbands.
EDIT: No sub. The ls50 is so well integrated throughout the tonal spectrum that I somehow feel that a sub would be a mistake - it woudl simply be too hard to integrate without an obvious disparity at the tonal intersection.
I just found and read your review. As you probably gather from my comments I pretty much agree with most, if not all, of the points that you make.
And yes, they are certainly not embarrassing themselves when playing with (much much) more expensive gear.
And yes, they are certainly not embarrassing themselves when playing with (much much) more expensive gear.
You are right that you are missing many of the fundamental tones which is why I feel subs are mandatory unless you like the type of sound you describe above.
Instead of people going on their 'feelings' or 'hunches,' why not try integrating a sub and then report back? I think the biggest mistake you could make (other than not trying a sub) would be to set the crossover frequency too high on the sub because that could cause your worst fears to materialize. Try setting your crossover at 40Hz as a starting point and keep the level of the sub turned down so that the sub isn't calling attention to itself. And I say this assuming you have a decent quality sub or subs to work with. In my room, I still have the disappearing act the LS50s pull off along with their electrostatic-like purity they exhibit across their frequency response. I also have some real bottom end response that I feel blends seamlessly with the LS50s to create a coherent sound.
Thanks for all the details of your listening session. We agree on the premise of a sub. I guess there are those who disagree with us. Of course a sub can be used, but at the expense of integration blues for some, but
maybe not all listeners.
I agree the LS50 are just amazing on vocals. Amazing.
Thank you for reading. KEF has something special here, but as we both agree, they must be used as with ALL small monitors, in proper context.
I wonder if KEF would consider making a scaled up version of the LS50. Larger cabinet and driver, maybe price it around $2500. That would be
very interesting!
How would you know if you never tried?? Unless you know from experience that you have a room that just won't support accurate deep bass because of a myriad of issues regardless of the quality of the sub used, you won't know if you can successfully integrate a sub with the LS50s until you try. I for one am not going to live without almost 2 full octaves of bass information. Who wants to hear a standup bass sound like rubber bands as truthspinner described it? I listen to lots of jazz and I couldn't deal with that type of sound. I'm more into the type of sound that almost makes a holographic image of the bass player plucking the strings of his acoustic bass to the point where you think you could get up and touch the image because it's so real.
Maybe I should repeat. I don't like subs. Period. I have no reason to try, and I can tell you for certain, neither John Atkinson or Neil Gader at TAS used subs.
I can tell you KEF did not demonstrate at Newport with subs. The LS50s work absolutely brilliantly on their own in an intimate setting.
The bottom line is that I use a floor stander that provides all the clean and deep bass I need. I have a pair of Compact 7ES3s that go far deeper than the LS50.
So maybe the answer is...um..a speaker that goes lower, and yet still does everything right?
How about the KEF R series which uses the Uni Q driver? The LS50 is not the only good speaker on the market, and room shaking bass lovers should
look elsewhere.
Also note I said some listeners will be perfectly happy with an LS50 and a sub.
My subs are almost $2K each so I get your point. To put that in perspective, the Sound Anchor stands I had custom made for the LS50s cost over half as much as the LS50s. Does that mean I shouldn't have bought the Sound Anchor stands? So yeah, if you are going to run out to Circuit City and buy a pair of $200 boom box subs and hope to integrate them with the LS50s, that won't work. Those kind of subs suck and they won't integrate with any speakers-never mind the LS50s. All I'm saying is the SQ from the LS50s is way beyond speakers that typically sell in their price range and they deserve to be played back with the best components you can afford. So if you want to caveat what I'm saying about using subs by saying that they must be really good subs, I'm fine with that. And if you want to continue to say that you don't think or feel that subs can be successfully integrated with the LS50s, you should clarify that statement by saying you can't integrate cheap subs successfully.
Then let me clarify, trying to integrate the LS50s with cheap subs is an exercise in futility. So now does it make sense for one to go out and spend,
let's say, $1500 or $2000 on a sub for $1500 speakers? I think not. That $3500 will get you really good, integrated speaker. I think this closes
the discussion on subs.
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