First time Naim Nait 5si - speakers and set up choice

RaghuV posted:

Thanks for the review. I had gone through it, and did not quite know how to translate it for thinking about the Naim.

The amps used were middle of the road entry level amps & he was happy with the results;  I translate that as your 5Si should be well able to handle the LS50's,  as in my experience watt for watt,  with its more robust power supply,  Naim amps will normally outperform other amps in ability to deliver the heavy currents needed for bass & dynamics while at the same time maintain cohesion of mid & treble detail.    

Looking further I read Naim show the 5Si as 60w/8ohms & 90w/4ohms.  Then further digging I read in the Stereophile review test that it shows it starts to clip (the limit) at 76w/8ohms  and 115w/4ohms,  both way higher than the Naim spec.  So you have a good robust power supply & a pretty good amp to handle the KEF recommended amp rating for the LS50 of 25 to 100W.

Just quoting the impedance minimum, isn't sufficient to characterise the 'difficulty' of a loudspeaker load, you also need the phase angle and impedance at the maximum power factor point, and the DC Resistance of the Bass/Mid driver (to determine transient load).  For an 8Ω nominal speaker to drop to 3.7Ω, either shows that it's not really 8Ω, or that the impedance has wild variations and hence is likely to have large phase angle excursions.

For reference the SP2s I use are 8Ω nominal
Bass/Mid driver DC Resistance 6.8Ω
Min Impedance 6.3Ω (@3.5kHz)
Impedance at Max Power factor approx 15Ω
Max Phase Angle 42°

Even this isn't quite enough to determine 'difficulty' but it goes a long way to it (and these figures indicate that the speaker's an easy load).

RaghuV posted:

This?

 

No - a ground isolator is a Galvanic Isolator - which effectively is 0 MHz or DC - so the above would not be an effective  galvanic or ground isolator.

Huge posted:

Just quoting the impedance minimum, isn't sufficient to characterise the 'difficulty' of a loudspeaker load, you also need the phase angle and impedance at the maximum power factor point, and the DC Resistance of the Bass/Mid driver (to determine transient load).  For an 8Ω nominal speaker to drop to 3.7Ω, either shows that it's not really 8Ω, or that the impedance has wild variations and hence is likely to have large phase angle excursions.

For reference the SP2s I use are 8Ω nominal
Bass/Mid driver DC Resistance 6.8Ω
Min Impedance 6.3Ω (@3.5kHz)
Impedance at Max Power factor approx 15Ω
Max Phase Angle 42°

Even this isn't quite enough to determine 'difficulty' but it goes a long way to it (and these figures indicate that the speaker's an easy load).

In plain English, the Naim should be able to drive the Kef Ls50 reasonably?

RaghuV posted:

Huge posted:

Just quoting the impedance minimum, isn't sufficient to characterise the 'difficulty' of a loudspeaker load, you also need the phase angle and impedance at the maximum power factor point, and the DC Resistance of the Bass/Mid driver (to determine transient load).  For an 8Ω nominal speaker to drop to 3.7Ω, either shows that it's not really 8Ω, or that the impedance has wild variations and hence is likely to have large phase angle excursions.

For reference the SP2s I use are 8Ω nominal
Bass/Mid driver DC Resistance 6.8Ω
Min Impedance 6.3Ω (@3.5kHz)
Impedance at Max Power factor approx 15Ω
Max Phase Angle 42°

Even this isn't quite enough to determine 'difficulty' but it goes a long way to it (and these figures indicate that the speaker's an easy load).

In plain English, the Naim should be able to drive the Kef Ls50 reasonably?

There's no way to know as KEF don't publish the required information.

The only ways to tell are:
1   To try it, then try other different speakers (particularly both known difficult and known easy types) and compare the results.
2   Buy the test equipment and do the electrical measurements yourself.

People like Frank have enough experience to give estimates based on option 1.

I put the KEF LS50s on hold. i figure I may do some more homework on an easier to drive speaker.

One thing to note:

I presume your Nait is integrated with your AV set up, for front L and R duties.

If so, you really should observe a fact that the speakers, especially front L and R and the centre one should be the same, same parameters, from the same manufacturer. This is quite important when a surround playback starts. A centre channel carries up to 50% of a soundtrack in movies and it should match the redt of the 'front'. 

You need to avoid an unballanced front centre vs front L/R with different sound signatures.

Adam

With the advent of a new set of bookshelves, I plan to leave the B&W surround setup alone for home theater duties and use the Naim Nait 5si and the Kef Ls50 for music purposes.

This should avoid the matching problem. 

The same dealer carries the KEF R300 and also the Focal Aria 906 at about the same price.

Any thoughts on these versus the KEF LS50?

Just becasue those speakers are small, doesn't mean you should really put them on bookshelves They work best on dedicated stands....

Would floor standers be an option for you?

My wife reluctantly let me get the KEF LS50 and weighed in on color choices (limited edition black with blue tweeter). So plonking for a new set of floors standers would cause some domestic trouble! She has already asked me to swap out the rather bulky B&W set with smaller things!

I am planning to move out the entire home theater kit to the living room, and use the study for the Naim and  LS50 (or alternative) mounted on heavy speaker stands, or on a cabinet with isoacoustic low height stands.

- Just understood what you meant - I meant bookshelf speakers, not bookshelves! Our house is already packed to the hilt with bookshelves in every room! Another source of concern!

RaghuV posted:

The same dealer carries the KEF R300 and also the Focal Aria 906 at about the same price.

Any thoughts on these versus the KEF LS50?

The Focals are easy to drive, and I imagine they would be a better match. The fact that they are not hideous looking is another advantage. 

Unless you are literally placing them in bookshelves, I never could see the point of small speakers on stands. A similar sized floor stander almost always has superior performance, imo. Of course some exceptions do exist ( Kans, n-sat's for example ) that work well coupled to a rear wall and are out of the way. Sticking small speakers on stands sitting out in the room does not make sense to me...

ATB,

Mark

varyat posted:

Unless you are literally placing them in bookshelves, I never could see the point of small speakers on stands. A similar sized floor stander almost always has superior performance, imo. Of course some exceptions do exist ( Kans, n-sat's for example ) that work well coupled to a rear wall and are out of the way. Sticking small speakers on stands sitting out in the room does not make sense to me...

ATB,

Mark

Small standmounters can have a 'quicker' sound and have less cabinet colouration.  If needed the reduced bass extension can be compensated for by using a sub.

The Focals are easy to drive, and I imagine they would be a better match. The fact that they are not hideous looking is 

Hungryhalibut posted:

RaghuV posted:

The same dealer carries the KEF R300 and also the Focal Aria 906 at about the same price.

Any thoughts on these versus the KEF LS50?

The Focals are easy to drive, and I imagine they would be a better match. The fact that they are not hideous looking is another advantage. 

I think the KEFs look beautiful in black and blue!

Freshly unboxed, and set up crudely on the cabinet. Blue and black, limited edition.

Speaker stands don't arrive till next week, and grand re-engineering of moving the home theater setup out of the study to the living room is still a while away.

But damn, Miles, Etta James, and Coldplay live, and Steely Dan never sounded so good at home!

The fine tuning and setups aside, I am already ecstatic.

Its going to be a long night!

Thanks for the all the advice.

 The Duke and "Blues in Orbit".

Man oh man! I feel like a teenage girl seeing the Beatles live and up close.