KEF LS50 - for David@FrankHarvey

chebby

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When reading the KEF LS50 and R100 specs, I noticed their impedance both dip to 3.2 Ohms.

Looking at some other small (nominally 8 Ohm) speakers, they don't dip anything like as much. (Spendor SA1 minimum 6.3 Ohms, Spendor S3/5R2 minimum 6.2 Ohms, PMC DB1i minimum 6.3 Ohms, MA GX50 minimum 4.85 Ohms).

Is it right to say the 3.2 Ohm minimum impedance figure suggests quite a challenging load?
 

jiggyjoe

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Kef should really rate these speakers as 4 ohm nominal! A speakers minimum impedance really should be not much lower than 8/10 its nominal figure.

So for a 8ohm nominal speaker the minimum should be no lower than 6.4 ohms.

A 4ohm nominal speaker should not drop much below 3.2 ohms.

It also depends how reactive they are and whether there is a large phase shift around the minimum impedance.
 

Frank Harvey

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:grin: @LHC

chebby said:
When reading the KEF LS50 and R100 specs, I noticed their impedance both dip to 3.2 Ohms.

Looking at some other small (nominally 8 Ohm) speakers, they don't dip anything like as much. (Spendor SA1 minimum 6.3 Ohms, Spendor S3/5R2 minimum 6.2 Ohms, PMC DB1i minimum 6.3 Ohms, MA GX50 minimum 4.85 Ohms).

Is it right to say the 3.2 Ohm minimum impedance figure suggests quite a challenging load?

I didn't get a chance to try a much better amp (will do when they come in for demo), but the Nait XS and Audiolab 8200P power amp drove them fine. Most of my listening was done on an 8200CDQ CD pre and 8200P power amp system.
 
chebby said:
When reading the KEF LS50 and R100 specs, I noticed their impedance both dip to 3.2 Ohms.

Looking at some other small (nominally 8 Ohm) speakers, they don't dip anything like as much. (Spendor SA1 minimum 6.3 Ohms, Spendor S3/5R2 minimum 6.2 Ohms, PMC DB1i minimum 6.3 Ohms, MA GX50 minimum 4.85 Ohms).

Is it right to say the 3.2 Ohm minimum impedance figure suggests quite a challenging load?

That is low and certainly would imply a difficult load. As for 'challenging' it is all relative. I certainly would not like to drive them with a 12watt single-ended
valve amp! They should be listed as 4ohm nominal speakers.
 

Frank Harvey

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Apologies for the odd look - I think because I was shifting stuff around, copying and pasting, somethign weird has happened. I've edited it to put gaps inbetween paragraphs, but they're refusing to show up!
 

Frank Harvey

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I certainly did! I didn't get quite as much time as I'd have liked with them, but I will do soon.The LS50 sound isn't the sort of sound thats going to be instantly impressive. The presentation of these is something you have to listen to and adjust to for a while, a little like ATC, as many people will not be used to this sort of sound because many speakers out there are far from neutral.They're quite weighty little things, and "knocking" the cabinet like a door produces nothing more than a totally dead sound as though they're solid through and through. In fact, I'd say that they're just as well built, if not slightly better (due to their size), than the Reference series in this respect. At least you know the cabinet is having no effect on the end result...I played quite a few different tracks, some on the Naim ND5XS/Naim Nait XS, but mostly on the Audiolab 8200CDQ/8200P. As I did with the Concept Blade when I first heard them, I could appreciate what they were NOT doing. I don't think many people looked at the Concept Blade in that context, they were just treating it as another speaker and were expecting to be wowed because they were expensive. Nothing wrong in that, but these sorts of speakers need a slightly different approach when listening, I think.Straight away you can tell that there's no "bloom" to the midrange. It's clean, revealing, and lacking the warmth that shouldn't be there. I tried them with the bungs out - it'll be interesting to try them with the bungs in, as this should only affect the bass depth, and not the tonal balance of the LS50 due to it's design. Stereophonics' Mr.Writer, which isn't the best recorded track and can be quite muddled sounding, you can hear a lot of detail in what was going on, and I could hear the cymbal work more clearly, which sounded a little different than I've heard before on many speakers. Sneaker Pimps 6 Underground sounded nice. There's always lots of detail in overdubbed/sampled music which usually gets lost on bassy speakers, but it's all here. FNDMNTL's Serv It also sounded great, but in our demo room didn't quite hit the lower notes (like the lower note in 6 Underground), although I'll reserve judgement on the low bass until I can get a pair home and try them out properly in my own room, as my R300's at home are much clearer with better presence in the lower bass than the R300's in our demo room.

The Chili Peppers' Blood Sugar Sex Magic was sounding nice and tight, with nice weight to the kick drum, and with as much detail as I have heard on the snare drums (on more expensive speakers, I mean). The only boom I was hearing was our demo room, which isn't perfect. The first couple of tracks of the Atticus Ross/Trent Reznor Social Network soundtrack, whilst not having the scale and depth of the Blades, seemed just a detailed and energetic - the LS50 has even more in common with the Blades than the R series does.

I also think that the UniQ's benefit of it's wide dispersion and imaging is realised more fully with the LS50's, which I think is down to the fact that the cabinet is playing no part in the presented sound. Like the Blade cabinet, the front facia curves back from the driver, eliminating reflections that a flat front panel would normally introduce.

For AV, I like a lot of detail. Many hi-fi speakers don't cut it for me, but the R300's have been pretty amazing. Having recently tried out the Audiolab 8200AP in my system, they're sounding even better than ever, and have really opened up purely because of this processor. I could quite happily live with the current sound that I have. But after what I heard earlier, I need to get a pair of LS50's home and try them out directly against my R300's. As I mentioned earlier, I think time spent with these will reveal their true strengths, as they're not immediately apparent.Music used:Boards Of Canada - Music Has The Right To ChildrenFNDMNTL - SubductionRed Hot Chili peppers - Blood Sugar Sex magicQueens Of The Stone Age - No One KnowsSneaker Pimps - Becoming XStereophonics - Just Enough Education To PerformTrent Reznor/Atticus Ross - Social Network OST
 

Frank Harvey

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Big Chris said:
So...... Active crossovers... What's the deal?:?

:grin: ;) :grin:

7176935098_f5769f8f7c_m.jpg


:)
 

fr0g

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FrankHarveyHiFi said:
Music used:Boards Of Canada - Music Has The Right To ChildrenFNDMNTL - SubductionRed Hot Chili peppers - Blood Sugar Sex magicQueens Of The Stone Age - No One KnowsSneaker Pimps - Becoming XStereophonics - Just Enough Education To PerformTrent Reznor/Atticus Ross - Social Network OST

Whatever else you may be David, I applaud your taste in music. Particularly BoC, but I like everything on your list!!

edit...not heard FNDMNTL... which will hopefully be remedied with Spotify.

edit 2. That sounds a bit rude, it isn't supposed to be... :)
 

John Duncan

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fr0g said:
FrankHarveyHiFi said:
Music used:Boards Of Canada - Music Has The Right To ChildrenFNDMNTL - SubductionRed Hot Chili peppers - Blood Sugar Sex magicQueens Of The Stone Age - No One KnowsSneaker Pimps - Becoming XStereophonics - Just Enough Education To PerformTrent Reznor/Atticus Ross - Social Network OST

Whatever else you may be David, I applaud your taste in music. Particularly BoC, but I like everything on your list!!

edit...not heard FNDMNTL... which will hopefully be remedied with Spotify.

edit 2. That sounds a bit rude, it isn't supposed to be... :)

And finally, proof that, when it comes down to the actual *music*, we're all rather closer to each other than we think...
 

Frank Harvey

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I urge everyone to give FNDMNTL a go - great stuff, and they're always linking to free music and mixes on their Facebook page.

If I'd have had time, I'd have tried a hell of a lot more stuff out!
 

chebby

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85dB and minimum impedance of 3.2 Ohms has rather put me off LS50s and R100s though. (And their looks of course*). They'd destroy my M-CR603 (or themselves).

My next speaker upgrade** still looks like being PMC DB1s (in light oak or similar).

*Yes it does matter to me if something is only available in light sucking dark veneers or a gloss black finish that makes them look like £80 PC monitors from a distance (and showcases every dust particle).

** I will do it - even if it has to be a used pair - just can't say when.
 

fr0g

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chebby said:
85dB and minimum impedance of 3.2 Ohms has rather put me off LS50s and R100s though. (And their looks of course*). They'd destroy my M-CR603 (or themselves).

My next speaker upgrade** still looks like being PMC DB1s (in light oak or similar).

*Yes it does matter to me if something is only available in light sucking dark veneers or a gloss black finish that makes them look like £80 PC monitors from a distance (and showcases every dust particle).

** I will do it - even if it has to be a used pair - just can't say when.

Actually (I hate that word, but still), I LOVE the looks of the Kefs. If I put my ADMs where they deserve into my main Hi-fi listening position, then I'd also have a spare Arcam A80, which I reckon would drive them just fine (quoted "over 100 watts at 4 ohms"). So if I do that and decide to go for new PC(nearfield) monitors, I will certainly check them out. Although £800 will get me quite a bit from the local 4sound.se..
 

fr0g

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John Duncan said:
fr0g said:
FrankHarveyHiFi said:
Music used:Boards Of Canada - Music Has The Right To ChildrenFNDMNTL - SubductionRed Hot Chili peppers - Blood Sugar Sex magicQueens Of The Stone Age - No One KnowsSneaker Pimps - Becoming XStereophonics - Just Enough Education To PerformTrent Reznor/Atticus Ross - Social Network OST

Whatever else you may be David, I applaud your taste in music. Particularly BoC, but I like everything on your list!!

edit...not heard FNDMNTL... which will hopefully be remedied with Spotify.

edit 2. That sounds a bit rude, it isn't supposed to be... :)

And finally, proof that, when it comes down to the actual *music*, we're all rather closer to each other than we think...

+1

I'd be happy to share a pint of ESB with almost anyone here.

Futility is the word of the moment...that, and ZEN.

:)
 

The_Lhc

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John Duncan said:
fr0g said:
FrankHarveyHiFi said:
Music used:Boards Of Canada - Music Has The Right To ChildrenFNDMNTL - SubductionRed Hot Chili peppers - Blood Sugar Sex magicQueens Of The Stone Age - No One KnowsSneaker Pimps - Becoming XStereophonics - Just Enough Education To PerformTrent Reznor/Atticus Ross - Social Network OST

Whatever else you may be David, I applaud your taste in music. Particularly BoC, but I like everything on your list!!

edit...not heard FNDMNTL... which will hopefully be remedied with Spotify.

edit 2. That sounds a bit rude, it isn't supposed to be... :)

And finally, proof that, when it comes down to the actual *music*, we're all rather closer to each other than we think...

I expect it'll surprise no one to learn that I don't like anything off that list. FNDMNTL, no relation to Fundamental off of the 90's are they? They did a PWEI remix once, well, I say remix, they re-did the vocals completely themselves, quite an interesting version.
 

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