Directivity and response smoothess extraordinary! Bass response is typical for a small box, poor. Distortion in low end is problematic, subwoofer almost necessary
More measurements here KEF LS50 Meta Spinorama and Measurements | Audio Science Review (ASR) Forum
More measurements here KEF LS50 Meta Spinorama and Measurements | Audio Science Review (ASR) Forum
It would appear that the XO now is quite different as can be seen in the impedance sweeps which look more complex and the tweeter has a high peak. The step response of the Meta now shows the tweeter with a positive polarity but now is no longer time aligned with the woofer. It comes on a bit sooner.
New LS50 Meta impedance (substantially high peak at tweeter XO - not as easy of a load for an amp to drive and definitely needs a 4ohm capable amp):
Old LS50 impedance:
LS50 Meta step response (now off by 250usec):
Old LS50 step response (time aligned but inverted tweeter polarity):
KEF’s own spinorama does indeed look very good for directivity:
New LS50 Meta impedance (substantially high peak at tweeter XO - not as easy of a load for an amp to drive and definitely needs a 4ohm capable amp):
Old LS50 impedance:
LS50 Meta step response (now off by 250usec):
Old LS50 step response (time aligned but inverted tweeter polarity):
KEF’s own spinorama does indeed look very good for directivity:
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May as well throw these in too..
SoundStageNetwork.com | SoundStage.com - NRC Measurements: KEF LS50 Meta Loudspeakers
SoundStageNetwork.com | SoundStage.com - NRC Measurements: KEF LS50 Meta Loudspeakers
I'm sure that the "metamaterial" has much less of a subjective effect on sound quality than the 4db drop between 2 and 4khz from the original model, unless of course the metamaterial is responsible for that drop.
Step response tells that xo is now acoustically 4th order, 360deg phase wrap. XO circuit has more components and thus phase graph is different. Low bass is basically same, upper bass has been tilted at the expense of sensitivity.
LS50W has same kind of response and directivity, most likely 4th order xo as well.
KEF LS50 Wireless
KEF LS50 Wireless Aktivlautsprecher - FIDELITY online
KEF LS50 & LS50W - Why the huge price difference | Audio Science Review (ASR) Forum
LS50W has same kind of response and directivity, most likely 4th order xo as well.
KEF LS50 Wireless
KEF LS50 Wireless Aktivlautsprecher - FIDELITY online
KEF LS50 & LS50W - Why the huge price difference | Audio Science Review (ASR) Forum
Yes, impedance is even uglier than it was before. The accelerometer test showed superb results.
dave
dave
The original LS50 XO (on left) appears to have too few components to be 4th order unless the electrical filter coincided with the natural falloff.
