So, I bought a pair of LS50s...

[Cafad 3,604]

I recently bought a pair of KEF LS50 mini-monitors.  I did this for several reasons.  One is that they are a speaker that performs extremely well for their size, another is that they were, are and will probably continue to be very popular.  A third is that KEF, in their marketing wisdom, finally offered a pair of black speakers with blue drivers which I had been thinking about for months prior.  

 

And here's a picture of them boys and girls.

 

But I have to say that the main reason I bought them is that they are little bastards to drive and that is exactly what I wanted.  So many people have asked about amps to pair them with over the last few years it has almost become a bit of an industry stereotype.  These are not speakers that handle cheaper amps well, with their low minimum impedance and quite nasty phase plot they will (and have) give many amps a difficult time of it.  I remember how Adamg had quite a difficult time finding an amp that drove his pair of LS50s well and I recall him saying good things about the Burson PI160 and the Myryad Z142 (both of which I still have on hand and am itching to try), the SonOfAGum rated fairly well too I believe but he also had less than positive comments on several other amps that he trialed.

 

John Darko did an excellent article a while back where he did a 4 amp comparison on a pair of LS50s.  If you are interested in the speakers at all I highly recommend searching it out on DAR.

 

The little KEFs, IMO at least, don't fit into the normal allotment-of-coin-to-components rules, if you spend the usual % of your budget on speakers and source and then start looking for an amp you will be hard pressed to find one worthy.  The LS50s break the rules in that regard.  

 

So, what amps should we use on a pair of KEF LS50s?

 

Well, that is what I intend to find out.  Just as soon as I've run the little puppies in, stay tuned.

[joz 5,643]

If you could source an Elektra Reference I reckon it would make them behave nicely.

[Guest]

Careful not to break them, they are only tiny.

[joz 5,643]

The Elektra Reference is so so gentle, like an iron fist in a silk glove.

[Guest]

Be nice !! you don't want to smell them running in, Joz. 

[DoggieHowser 1,107]

Try a Plinius SA103. The Reference is beautiful with the LS50 though as you said, the allocation of coin is a tad crazy

I've been meaning to try the Devialets. Especially when they have an SAM for the LS50

[Josh_85 62]

I brought mine a month before the new colours came out after months of paying them off. Blue is my favourite colour and was thinking if only the driver came in blue when I brought them......................bit of an emotional issue haha. Congrats on the purchase, mine make me smile everyday.

Edited December 17, 2015 by Josh_85

[Cafad 3,604]

If you could source an Elektra Reference I reckon it would make them behave nicely.

Do they come as an integrated?  

It's not a deal breaker if they don't but it might just be a deal sealer if they do.

[Cafad 3,604]

Try a Plinius SA103. The Reference is beautiful with the LS50 though as you said, the allocation of coin is a tad crazy

I've been meaning to try the Devialets. Especially when they have an SAM for the LS50

Well I do know a guy with a SA100...

 

I believe there will be a mention made of a Devialet/LS50 combo before too long, but not from me I'm afraid.

[legselevens 835]

I still have a couple of pairs of Kef Reference series standmounts. The RDM2 and a pair of 101/2's which is a sealed cabinet speaker. The RDM is easy to drive and very easy to listen to. The 101/2 is like the problem twin. It plays within the rules if you don't push it but given a bit of reign in the amp department and you are well rewarded. The Hypex nc400's drive the 101/2's no problem and the Musical Fidelity A5 integrated wasn't far behind albeit a different sound signature. I'd guess that either of these two amps would work well with the LS50's. I hear good things about Plinius so will look forward to hearing one some time.

Edited December 17, 2015 by legselevens

[Qwertyqaz 788]

Try the ME850

[Cafad 3,604]

I really liked the ME25/DM38 combo on my Lenehans, I guess I'll have to try it out on the little KEFs at some point.  

 

Them all being under the same roof the question is when, not if.

[bebop 118]

The LS50 can really scale with the source and amp.

[Cafad 3,604]

The LS50 can really scale with the source and amp.

I'm noticing that already, and I'm only up to amp number 6, they seem to really accentuate the character of an amp.  In that respect they seem to be even better than I was hoping, and I had pretty high hopes.

[LHC 2,138]

An inverse question would be - how does it sound when driven by an under-powered amp? 

[DoggieHowser 1,107]

An inverse question would be - how does it sound when driven by an under-powered amp?

It's not lack of power. But lack of quality power.

[Cafad 3,604]

An inverse question would be - how does it sound when driven by an under-powered amp? 

Also a question I plan to answer*, hopefully without generating too much smoke.

 

 

*or plan to attempt to answer at any rate.

[johnnygohard 327]

I think one can conclude, good entry style speaker, bw 685s2 is way more bass direct, without sacrificing the metal tweeter helped mid range,kef runs out of puff well before other cheaper alternatives

[betty boop 15,742]

I dont know....kef and their tweeter perhaps it is ...but always not totally sat well with me...regardless of amplification and sources... in some various setups have heard...

[A J 1,978]

I think one can conclude, good entry style speaker, bw 685s2 is way more bass direct, without sacrificing the metal tweeter helped mid range,kef runs out of puff well before other cheaper alternatives

 

Yeah ... I dunno

I rate LS50's - they can pump prodigious base with the right amp 

[Conster 119]

You must hear the LS50 with a Luxman Class A integrated. Surprisingly good. Very detailed, transparent and open sounding.

[joz 5,643]

Do they come as an integrated?  

It's not a deal breaker if they don't but it might just be a deal sealer if they do.

Not yet, but apparently there could be one on the horizon.

But when , who knows?

[Cafad 3,604]

I think I might weed out the LS50 under performers in stages until I get down to a handful of amps.

 

Round 1, part 1.

 

Stello AI500.  I was impressed with the Stello's ability on the LS50s but since it was the first amp I tried I didn't have much experience to draw on.  After running the Job INT and ME240 I came to the conclusion that the Stello sounded a little on the hard side.  Not hard enough to sound bad as such but I did find that I preferred the later amps as much for the fact that they didn't sound hard as any other reason.  The Stello had plenty of power and certainly didn't seem to be breaking a sweat, there certainly didn't seem to be any excess heat generated from it.  The Stello is currently visiting JVenter so I'm going to remove it at round 1, if it was still here it would probably make round 2, but I can't be certain.

 

ME240 (now filled with hi-capped goodness).  Hell yeah!  The ME has finally reacted positively to my attempts to re-bias it (several attempts were required) and has regained much of that energy that I enjoyed back when it was overheating (Peter fixed the overheating issue but it just never sounded quite the same afterwards).  The ME240 has depth, dynamics and impact in spades, a great combination with the little KEFs.  Definitely moves on to round 2.

 

Job INT.  Very smooth with a very pleasing amount of detail in the treble.  That bass bump that was so evident on the Lenehan S2Rs comes across as a soft, forward smoothness in the lower bass on the LS50s.  It will definitely match the ME in the vocals and detail levels but I don't think it has the dynamic presentation to pull off a final win.  It does move on to round 2, but it does it cautiously.

 

CEC Amp3800.  Very warm, and I mean very.  It seems to be making a serious effort to push the sound signature of a digital system in the direction of vinyl and while it does manage it in the area of warm and cosy smoothness it doesn't pull it off in the area of depth or detail.  Initially I was very impressed but that was only because I liked the fact that it sounded so different to the other amps, once I got over the fact that it was different I realized that it really wasn't very impressive.  If you want a vinyl sound that badly you should really buy a record player.  Does not make it past round 1.

 

Xindak AE600.  An amp I love to death on the Lenehans just doesn't manage to impress on the LS50s.  When I was using the S2Rs if I closed my eyes the mighty Xindak gave me the impression that I was staring into infinity and getting music emerging from it, the little KEF's just don't convey that level of sound stage depth (and I think much of the effect was conveyed via the bass, which the Lenehans have in spades).  Does not pass round 1.  

 

YBA Heritage A100.  Something of a stand out performance here, the YBA gives a very dynamic performance (almost, but not quite, the level of the ME240) and manages to keep some of the warmth and richness that I remember from its pairing with the Lenehans.  I intended to just give it a quick preliminary listen when I swapped it in but liked it so much it stayed in use for 2 days.  It does get stonking hot, however since I liked it so much it was in use for much longer than the other amps so I'm not sure if this is an issue just yet.  Definitely passes round 1.

 

Now admittedly the Stello and the Xindak are probably a bit on the expensive side for most people who are planning on buying a pair of LS50s so removing them in round one makes sense from more than just a sonic performance point of view.  The Job is the most expensive of the remaining amps at $2500 AU, the YBA at $1650 (on special from $2K), the CEC at $900 (on special from $1500), and an ME240, if you can find one, generally comes in around $1K second hand.

 

Sorry for the lack of pics, I might start taking fresh ones when I get to round 2.  At the moment I'm only halfway through round 1 so pics are at least a week away (sorry @Luc).

Edited December 18, 2015 by Cafad

[Telecine 3,914]

Try a Primare i30 integrated amp

[Cafad 3,604]

Try a Primare i30 integrated amp

An I30 specifically or would an I32 do?

[betty boop 15,742]

primare is a great suggestion, what about a little redgum ?

[wikeeboy 646]

The Devialet 200 has plenty of get up and go for the ls50's. Using the SAM profile definitely turns them into a bigger sounding speaker with impressive bass but I like it loud and found myself bottoming them out too often. I preferred the Atohm GT1's but with an RRP of $5k they should be better.

[Telecine 3,914]

An I30 specifically or would an I32 do?

The i30 is Class A/B. I haven't heard the Class D i32 but someone else I know who has one likes it.

Edited December 18, 2015 by Telecine

[Qwertyqaz 788]

What are we trying to achieve

[mwhouston 4,888]

One of my Tripath 180W amps work well with these.

[legselevens 835]

Rogue Audio Sphinx 2? It's an integrated amp with a 12au7 in the preamp and uses class d for power. It has on board phono and headphones input too. Rated very well by stereophile.

Edited December 18, 2015 by legselevens

[mwhouston 4,888]

Rogue Audio Sphinx 2? It's an integrated amp with a 12au7 in the preamp and uses class d for power. It has on board phono and headphones input too. Rated very well by stereophile.

Are you using this amp with the LS50s?

How does the combo sound?

[djb 3,196]

@@mwhouston. "One of my Tripath 180W amps work well with these."

lol now that will aggravate the boys no end

[mwhouston 4,888]

@@mwhouston. "One of my Tripath 180W amps work well with these."

lol now that will aggravate the boys no end

I think the little KEFs would required a powerful amp to get the best out of them. Something which can deliver some heavy current. Most speakers, even high efficiency ones, seem to benefit from a gutsy amp. I love my flea power tube amps and on the Beymas they play loud. BUT the Beymas sound better with my current 250W Class D.

[Cafad 3,604]

What are we trying to achieve

To find out what works, what doesn't work and if possible to have some fun along the way.  The stretch goal is to find a really cheap amp that sounds absolutely fabulous on the LS50s, I'm not going to hold my breath until it happens but I'd like to think it's a real possibility.

 

 

One of my Tripath 180W amps work well with these.

You mean there is such a thing as a 180W tripath amp.  Please, tell me more.

[Cafad 3,604]

I think the little KEFs would required a powerful amp to get the best out of them. Something which can deliver some heavy current. Most speakers, even high efficiency ones, seem to benefit from a gutsy amp. I love my flea power tube amps and on the Beymas they play loud. BUT the Beymas sound better with my current 250W Class D.

Just after I unboxed the LS50s BRMSlash bought around a DIY class D power amp that he had built (around $350 in parts, if memory serves) and we hooked it up using the little breeze audio JC2 preamp (about $250 via ebay) and that combo worked an absolute treat.  I may ask to borrow the amp for a few days later on so I can get a really good listen in because for a measly $600 that was a good combo.

[robmid 476]

Just my two bob's worth.

 

Why is there a perceived price amp/speaker ratio when choosing a system? Especially matched with the LS50 which is in a class of it's own and capable of near ribbon/electrostatic performance carefully setup in a medium sized room with a serious amplifier. 

 

The LS50 is capable of performance way above it's price, so what is the point in compromising their incredible potential with an inferior amp? Why be disappointed?

 

Anthony Holton in Tassie hand builds superb studio quality amps that are raved about internationally. My 150 watt Holton twin mono kit cost around $1100 to build using Anthony's hand built modules or you can buy a twin mono block full built for around $2000.

[Cafad 3,604]

Just my two bob's worth.

 

Why is there a perceived price amp/speaker ratio when choosing a system? Especially matched with the LS50 which is in a class of it's own and capable of near ribbon/electrostatic performance carefully setup in a medium sized room with a serious amplifier. 

 

The LS50 is capable of performance way above it's price, so what is the point in compromising their incredible potential with an inferior amp? Why be disappointed?

 

Yep, my view pretty much exactly.  And yet people continue to buy them and then skimp on the amp, no matter what we tell them this is just what people do.  If they are going to do that anyway then we might as well at least try to guide them in a sensible direction.  Which is why I plan to sample amps from all directions and price points to give those silly, misguided, non-audio experienced people an idea as to what they might be missing.

 

And in the spirit of buying cheap amps I've just given the little Knobsound NS02 HD 1969, (which is something of a mouthful of a name) that cost me a massive $316 over ebay, a run on the LS50s.

I was a bit taken aback at first by how pleasing this little amp sounds, it did take 10 minutes to warm up but after that it was quite nice.  Nice highs, nice vocals, warm and lightly rich, a bit light on the lower bass but that was to be expected from a sub 20 watt amp (I'm assuming about 15 watts, actual stats don't seem to exist for this baby).  it does a pretty good job on the bass, but it loses out on the depth and doesn't have the power to convey a large scale sound stage either.  Even so I suspect if you had the LS50s on your desk, in a very near field set up, it would do a pretty fair job.  However when it comes to being able to hear instruments behind the main ones playing it just doesn't cut it, there is some rather nice piano in the background of several of Evanescence's songs and it is barely audible on the little Knobsound so it doesn't do so well on levels of background detail.  So, it won't be making it to round 2.

 

I'm still waiting to hear more about this 180W tripath though @@mwhouston.

[Jventer 1,672]

Yep, my view pretty much exactly.  And yet people continue to buy them and then skimp on the amp, no matter what we tell them this is just what people do.  If they are going to do that anyway then we might as well at least try to guide them in a sensible direction.  Which is why I plan to sample amps from all directions and price points to give those silly, misguided, non-audio experienced people an idea as to what they might be missing.

 

And in the spirit of buying cheap amps I've just given the little Knobsound NS02 HD 1969, (which is something of a mouthful of a name) that cost me a massive $316 over ebay, a run on the LS50s.

I was a bit taken aback at first by how pleasing this little amp sounds, it did take 10 minutes to warm up but after that it was quite nice.  Nice highs, nice vocals, warm and lightly rich, a bit light on the lower bass but that was to be expected from a sub 20 watt amp (I'm assuming about 15 watts, actual stats don't seem to exist for this baby).  it does a pretty good job on the bass, but it loses out on the depth and doesn't have the power to convey a large scale sound stage either.  Even so I suspect if you had the LS50s on your desk, in a very near field set up, it would do a pretty fair job.  However when it comes to being able to hear instruments behind the main ones playing it just doesn't cut it, there is some rather nice piano in the background of several of Evanescence's songs and it is barely audible on the little Knobsound so it doesn't do so well on levels of background detail.  So, it won't be making it to round 2.

 

I'm still waiting to hear more about this 180W tripath though @@mwhouston.

Fully agree, the answer is in the amp/speaker combination.

That is why I am going to try the Stello amp on speakers that cost less than half of the amp.

[legselevens 835]

Are you using this amp with the LS50s?

How does the combo sound?

No I'm still using the nc400's with the valve preamp. I read about it when reading on Magnepans and it was considered a nice combo. I would imagine it would work well with the LS50's too. It's available in Australia as far as  know.