Naim Nait 5si with Kef LS50 good match?

[criant]

I listened the kef LS50 with Cambridge cxa80 and I loved them.
the seller told me that is a good match with naim nait 5si (60w) because it is very current.someone has this combination, or listened to him?My sistem is:Naim nait 5si Audiolab M-dac Subwoofer Rel T5 room 16 mq

 

[ChrisIRL]

I had this combo and it didn't work out for me. The LS50s are great speakers and the 5si is a great amp. The 5si just seemed to overpower the LS50s a touch if the volume was pushed at all. I don't think the small drivers of the Kefs could handle the very weighty bass output of the 5si. This resulted in a distorted sound above moderate volume. Highs also suffered, and were quiet bright and piercing. Naim and metallic tweeters don't mix imo.

 

[nopiano]

You should be able to find many previous threads about matching amps with the LS50, mostly from two or three years ago when it first came out. There was one every week at the time - or at least it felt like that!

Pace Chris' experience, they have been quite often matched with Naims of various types, and like many very good speakers, can get better even with very pricy amplification. Simply, get the best you can afford!

There is no substitute for you listening in your room, with your speakers on your stands, however.

 

[Jota180]

I had the LS50 with a NAP 100 power amp (50W into 8 Ohm and 75W into 4 Ohm) and it was fine at low to lower middle volumes but push it harder and it just didn't work sonically. The impedance on the LS50 dips to 3.2 Ohms at certain frequencies and the amp struggled to control the speakers at middle to higher volumes. I emailed a guy from KEF asking about amplifiers for the LS50 who said pretty much what I experienced.

I bought a Hegel H160 amp, 150W 8 Ohm 250W 4 Ohm, and the difference with the KEF's when I turned the volume up with that amp was clear. The KEF's really are incredible for their size and if you have your heart set on them and like playing music louder on occasions I'd be inclined to look for an amp with more power into 8 and 4 Ohms.

 

[Jota180]

I had this combo and it didn't work out for me. The LS50s are great speakers and the 5si is a great amp. The 5si just seemed to overpower the LS50s a touch if the volume was pushed at all. I don't think the small drivers of the Kefs could handle the very weighty bass output of the 5si. This resulted in a distorted sound above moderate volume. Highs also suffered, and were quiet bright and piercing. Naim and metallic tweeters don't mix imo.

You have that the wrong way round. The amp didn't have enough power to control the drives of the speakers. When I switched from a NAP 100 to a Hegel H160 the KEF's went unbelievably loud without distortion compared to the Naim. The NAP 100 was great at lower volumes but didn't have the ponies to push the KEF's and control them at the same time.

 

[ChrisIRL]

I don't know about that. Maybe it's the low damping of the 5si but I've never seen any amp generate so much movement of speaker cones. The 5si could drive my ATC SCM11s to very high volumes with no loss of control. Even at lower volumes the SCM11 cones moved like no other amp I used. It's a big full weighty bass. You could see clearly the LS50s were physically at their limit. There doesn't seem to be much excursion possible in that flat rubber surround the 50s have. A brio r could push them to higher volumes than the 5si because the bass was much leaner. My current Sonus Faber toy towers also dip to 3ohms and the 5si has no issue. The piercing highs were at any volume too. That pairing used to give me headaches.

 

[Q5]

I don't know about that. Maybe it's the low damping of the 5si but I've never seen any amp generate so much movement of speaker cones. The 5si could drive my ATC SCM11s to very high volumes with no loss of control. Even at lower volumes the SCM11 cones moved like no other amp I used. It's a big full weighty bass. You could see clearly the LS50s were physically at their limit. There doesn't seem to be much excursion possible in that flat rubber surround the 50s have. A brio r could push them to higher volumes than the 5si because the bass was much leaner. My current Sonus Faber toy towers also dip to 3ohms and the 5si has no issue. The piercing highs were at any volume too. That pairing used to give me headaches.

I run a pair of a Arcam FMJ A49 and cannot get the Kefs to a distortion level, my ears hurt well before that.

 

[CnoEvil]

I run a pair of a Arcam FMJ A49 and cannot get the Kefs to a distortion level, my ears hurt well before that.

Same here, except it's an Arcam AVR600

 

[ChrisIRL]

Well I have no reason to knock the LS50s or to promote the 5si. I think both are excellent but just not together. It didn't work and having experienced what the 5si can do with ATC SCM11s it wasn't because of lack of power. Maybe the low damping of the 5si could be the issue, what are the above amps specifications re damping factor. A Roksan Kandy k2 BT at 150 wpc didn't get the ATC drivers moving the way the 5si did. Again I have no need to be making this up.

 

[davedotco]

Are usually a bad thing, unless you are playing very loud indeed.

The LS50 is a ported design, so there is no acoustic loading on the bass driver an octave below the port tuning. Ie the cone moves a long way even at modest levels. This is the nature of any ported speaker.

Once the cone is unloaded in this way it becomes difficult to control, particularly by an amplifier like the Naim which has a higher than average output impedance. The result is an out of control bass driver that sounds horrible. (it may also be breaking up, so this may be the source of the excessive brightness)

Sealed speakers like the ATC have much better and more consistent loading below the resonant frequency, so the bass drivers will not move so much. That said the ATC uses a powerful magnet and relatively heavy cone, so will probably work better with an amplifier with a low output impedance.

 

[ChrisIRL]

What I love about this forum is very often the only person who actually owned the products being discussed in a thread is the one told they are wrong.

The LS50 are usually capable of easily handling serious volume and bass, I know this well. They are an impressive speaker.

The 5si is capable of driving demanding speakers with no loss of control. With other amps the SCM11 cones didn't perceptibly move at all, ever. With low bass notes at moderate volume the 5si made them show some sign of life. Maybe this is technically a bad thing, it didn't sound bad at all. I would have thought it normal. Regardless of moving cones or not there was zero audible distortion with this pairing.

At not much above moderate volumes the cones of the 50s looked like they were going to jump out of the cabinets hooked up to the 5si. It wasn't normal, I never observed movement like that with other amps I used with the 50s even at much higher volumes. But then I've never heard another amp capable of the bass a 5si can produce. Not boomy, not boosted but just very weighty, full and punchy. Too much for the 4.75 inch ( not 5.25 inch) drivers of the LS50s to handle. They do bass but on their terms.

The LS50s do not place any greater demand on the 5si than the ATCs or my current toy towers yet it drives either of these speakers beautifully.

 

[plastic penguin]

It is all about synergy. Not heard the Kefs with Naim but PMC, Neat and B&W 805S work very well when partnered with Naim.

IMHO LS50s work well in smallish spaces but bigger cabinets will yield a more pleasurable experience with extra breathing space.

 

[gasolin]

I don't know about that. Maybe it's the low damping of the 5si but I've never seen any amp generate so much movement of speaker cones. The 5si could drive my ATC SCM11s to very high volumes with no loss of control. Even at lower volumes the SCM11 cones moved like no other amp I used. It's a big full weighty bass. You could see clearly the LS50s were physically at their limit. There doesn't seem to be much excursion possible in that flat rubber surround the 50s have. A brio r could push them to higher volumes than the 5si because the bass was much leaner. My current Sonus Faber toy towers also dip to 3ohms and the 5si has no issue. The piercing highs were at any volume too. That pairing used to give me headaches.

I run a pair of a Arcam FMJ A49 and cannot get the Kefs to a distortion level, my ears hurt well before that.

ha ha it's also a 200watt in 8 ohm and 400 watt in 4 ohm amp, that's 108db in 8 ohm and 111 db in 4 ohm, since max spl is rated at 106db it's only 100-125 watt.

I'm also more then fine with my 50 watt or 100 watt peak in 8ohm and 89db, my amp has actually been tested with B&W 803 and it sounded very good, my speakers only goes down to 4.4 ohm so they are not that bad

 

[pyrrhon]

What I love about this forum is very often the only person who actually owned the products being discussed in a thread is the one told they are wrong.

The LS50 are usually capable of easily handling serious volume and bass, I know this well. They are an impressive speaker.

The 5si is capable of driving demanding speakers with no loss of control. With other amps the SCM11 cones didn't perceptibly move at all, ever. With low bass notes at moderate volume the 5si made them show some sign of life. Maybe this is technically a bad thing, it didn't sound bad at all. I would have thought it normal. Regardless of moving cones or not there was zero audible distortion with this pairing.

At not much above moderate volumes the cones of the 50s looked like they were going to jump out of the cabinets hooked up to the 5si. It wasn't normal, I never observed movement like that with other amps I used with the 50s even at much higher volumes. But then I've never heard another amp capable of the bass a 5si can produce. Not boomy, not boosted but just very weighty, full and punchy. Too much for the 4.75 inch ( not 5.25 inch) drivers of the LS50s to handle. They do bass but on their terms.

The LS50s do not place any greater demand on the 5si than the ATCs or my current toy towers yet it drives either of these speakers beautifully.

the 5si that I had for a year came in replacement of a nad 275bee and produced the same bass slam wich is a feat. Its a powerfull puchy little beast. Its also the most revealing amp I had. But i did notice that when a recording had distoriton and big bass the cone distorted.

A year ago I posted that http://www.whathifi.com/forum/hi-fi/need-help-bad-song-or-my-system and I have come to realize that the 5si exposes bass distortion in a very rude way. I also had probelm with haxan cloak very low bass where one of the wire that connect to the coil in the woofer would touch the cone and make a buzzing sound because of extreme woofer throw.

So I totally beleive you !

To the OP I would not match the 5si with the ls50, its going to bee too analytical. Bu to the defense of the 5si its the most exciting shiver making amp ever ! totally eats the hegel in that regard.

 

[Jota180]

What I love about this forum is very often the only person who actually owned the products being discussed in a thread is the one told they are wrong.

The LS50 are usually capable of easily handling serious volume and bass, I know this well. They are an impressive speaker.

The 5si is capable of driving demanding speakers with no loss of control. With other amps the SCM11 cones didn't perceptibly move at all, ever. With low bass notes at moderate volume the 5si made them show some sign of life. Maybe this is technically a bad thing, it didn't sound bad at all. I would have thought it normal. Regardless of moving cones or not there was zero audible distortion with this pairing.

At not much above moderate volumes the cones of the 50s looked like they were going to jump out of the cabinets hooked up to the 5si. It wasn't normal, I never observed movement like that with other amps I used with the 50s even at much higher volumes. But then I've never heard another amp capable of the bass a 5si can produce. Not boomy, not boosted but just very weighty, full and punchy. Too much for the 4.75 inch ( not 5.25 inch) drivers of the LS50s to handle. They do bass but on their terms.

The LS50s do not place any greater demand on the 5si than the ATCs or my current toy towers yet it drives either of these speakers beautifully.

Dave gave a clear explanation why the sound could get out of shape and to be honest the guy who worked at KEF told me in an email that my NAP 100 would be fine at low to lower middle volumes but wouldn't be recommended for anything higher than that. I owned the LS50 and NAP 100 and my own experience after replacing the NAP 100 with the H160 pretty much confirmed what I was told in the email. The difference was clear. The bass control at mid to higher volumes, the H160 is in another league from the NAP 100 which is probably to be expected given the price disparity.

 

[nopiano]

The bass control at mid to higher volumes, the H160 is in another league from the NAP 100 which is probably to be expected given the price disparity.

I am sure that is right, as Hegel make a point about the very low output impedance, whereas Naim deliberately raise theirs (though I've always wondered if that is because the amps would otherwise be unstable, which seems odd given how good they can sound).

 

[davedotco]

What I love about this forum is very often the only person who actually owned the products being discussed in a thread is the one told they are wrong.

The LS50 are usually capable of easily handling serious volume and bass, I know this well. They are an impressive speaker.

The 5si is capable of driving demanding speakers with no loss of control. With other amps the SCM11 cones didn't perceptibly move at all, ever. With low bass notes at moderate volume the 5si made them show some sign of life. Maybe this is technically a bad thing, it didn't sound bad at all. I would have thought it normal. Regardless of moving cones or not there was zero audible distortion with this pairing.

At not much above moderate volumes the cones of the 50s looked like they were going to jump out of the cabinets hooked up to the 5si. It wasn't normal, I never observed movement like that with other amps I used with the 50s even at much higher volumes. But then I've never heard another amp capable of the bass a 5si can produce. Not boomy, not boosted but just very weighty, full and punchy. Too much for the 4.75 inch ( not 5.25 inch) drivers of the LS50s to handle. They do bass but on their terms.

The LS50s do not place any greater demand on the 5si than the ATCs or my current toy towers yet it drives either of these speakers beautifully.

You clearly have misunderstood.

The kefs are ported speaker, the loading on the bass driver is fundamentally different from that on a bass driver in a sealed enclosure such as the ATCs.

The cone movement you are witnessing on the Kefs (but not on the ATCs) is caused by this difference and occurs an octave below the port frequence (around 30-35Hz in this case). This happens to all ported loudspeakers to a greater or lesser degree depending on the design.

It also depends on the amplifier, some will have a lower output impedance than others and these will control the movement of the bass cone better than those amplifiers with a higher output impedance, such as the Naim. This explains the excessive movement with one amplifier and much lesser movement with other, simple explanations in accord with the science of loudspeaker and amplifier design.

 

[ChrisIRL]

I understood what you were saying. Even a ported design must have some limits to the amount of cone excursion it's comfortable with. If examined closely the LS50 driver design does not allow for a lot of movement, the cone is small and stiff, the rubber surround flat and very narrow. The suggestions that the 5si didn't have the power to drive the 50s is nonsense. I drove them happily with lowered powered amps, Rega brio r, Arcam a19 and heard no distortion even pushed hard and did not see the extreme cone movement as with the 5si. Whatever the reason it was not lack of power. I've driven equally difficult speakers with the 5si without any problems at all.

 

[TrevC]

What I love about this forum is very often the only person who actually owned the products being discussed in a thread is the one told they are wrong.

The LS50 are usually capable of easily handling serious volume and bass, I know this well. They are an impressive speaker.

The 5si is capable of driving demanding speakers with no loss of control. With other amps the SCM11 cones didn't perceptibly move at all, ever. With low bass notes at moderate volume the 5si made them show some sign of life. Maybe this is technically a bad thing, it didn't sound bad at all. I would have thought it normal. Regardless of moving cones or not there was zero audible distortion with this pairing.

At not much above moderate volumes the cones of the 50s looked like they were going to jump out of the cabinets hooked up to the 5si. It wasn't normal, I never observed movement like that with other amps I used with the 50s even at much higher volumes. But then I've never heard another amp capable of the bass a 5si can produce. Not boomy, not boosted but just very weighty, full and punchy. Too much for the 4.75 inch ( not 5.25 inch) drivers of the LS50s to handle. They do bass but on their terms.

The LS50s do not place any greater demand on the 5si than the ATCs or my current toy towers yet it drives either of these speakers beautifully.

You clearly have misunderstood.

The kefs are ported speaker, the loading on the bass driver is fundamentally different from that on a bass driver in a sealed enclosure such as the ATCs.

The cone movement you are witnessing on the Kefs (but not on the ATCs) is caused by this difference and occurs an octave below the port frequence (around 30-35Hz in this case). This happens to all ported loudspeakers to a greater or lesser degree depending on the design.

It also depends on the amplifier, some will have a lower output impedance than others and these will control the movement of the bass cone better than those amplifiers with a higher output impedance, such as the Naim. This explains the excessive movement with one amplifier and much lesser movement with other, simple explanations in accord with the science of loudspeaker and amplifier design.

Or, to put it very simply, in an infinite baffle speaker the bass cone excursion is damped by the air in the sealed cabinet.

 

[TrevC]

I understood what you were saying. Even a ported design must have some limits to the amount of cone excursion it's comfortable with. If examined closely the LS50 driver design does not allow for a lot of movement, the cone is small and stiff, the rubber surround flat and very narrow. The suggestions that the 5si didn't have the power to drive the 50s is nonsense. I drove them happily with lowered powered amps, Rega brio r, Arcam a19 and heard no distortion even pushed hard and did not see the extreme cone movement as with the 5si. Whatever the reason it was not lack of power. I've driven equally difficult speakers with the 5si without any problems at all.

Were you playing vinyl? I ask because I'm wondering if it was caused by subsonic stuff that should be filtered out by the preamp.

 

[davedotco]

I understood what you were saying. Even a ported design must have some limits to the amount of cone excursion it's comfortable with. If examined closely the LS50 driver design does not allow for a lot of movement, the cone is small and stiff, the rubber surround flat and very narrow. The suggestions that the 5si didn't have the power to drive the 50s is nonsense. I drove them happily with lowered powered amps, Rega brio r, Arcam a19 and heard no distortion even pushed hard and did not see the extreme cone movement as with the 5si. Whatever the reason it was not lack of power. I've driven equally difficult speakers with the 5si without any problems at all.

It is nothing to do with power. It is about control, impedance matching, damping factor, call it what you will.

The Naim is known to have a higher than usual output impedance so struggles to control the bass cone, they are designed this way which will make them unsuitable for certain speakers.

This may well be an extreme example of this kind of mismatch, but that is what it is and the reasons for it are quite straightforward.

 

[ChrisIRL]

I did say the mismatch was likely due to damping factor. Low damping factor is how Naim do big bass. That this would cause extreme cone excursion or loss of cone control in the small LS50s drivers is pretty much saying the same thing. It resulted in distortion but this was not due to the 5si not having the ponies as it was put. It's just an unsuitable match.

 

[davedotco]

This reached a peak during Naim's 'olive' period where it was very difficult to pair their amplifiers with speakers offering real bass extension. This made the speaker choice very difficult, many perfectly good speakers sounded overblown in the bass, or in 'Naim speak', out of tune.

Many dealers were convinced that this was the fault of the speakers (some still do) when it was an amplifier problem.

 

[TrevC]

The LS50 isn't really capable of serious deep bass, is it? It's only a little thing.

 

[plastic penguin]

The LS50 isn't really capable of serious deep bass, is it? It's only a little thing.

No, seriously powerful bass for cabinet size, as I found out when the Leema put them through their paces.