Somewhere in diyaudio is a Thread including a description of modifications to the crossover in a member's KEF iQ3 loudspeakers.
I saw it by chance about a month ago, but silly me did not take note of its Title or Starter.
Now I cannot find that Thread using Search - perhaps because Search will not accept the 3 letter words KEF and iQ3.
Does anyone here know how to find that Thread ?
Many of you will know that the driver in these KEFs is a Uni-Q , or UniQ as some abbreviate its spelling to,
but applying those in Search does not find it either !
The iQ3 pair I have here are a 2007 assembled pair -{the date is stamped inside the cabinet}-
and the crossover board there-in seems very difficult to remove.
It will probably have to have the tops of four nylon posts cut off, or the four corners of its pcb cut off to be able to get it out.
This version has 3 electrolytic caps, which I cannot see the uF printed on in the position they are on the pcb,
nor can I see the ohms of one of the resistors.
The second resistor is 6.8ohm.
There is a small 0.125mH air-core inductor, and a 1.1mH metal ccored inductor.
Both of those have labels stuck on them.
The sound of the treble is what one would expect after signal passing through two electrolytic caps,
and my guess is there is a 3rd order treble filter used.
I intend to replace these with polypropylene caps, and I probably will for the electro cap in the bass filter also.
I see that for the new KEF iQ30 that KEF state having lowered the crossover frequency from the 2.7kHz of the iQ3 to 2.5kHz for the iQ30.
My guess is that this is to reduce audibility of the upper midrange breakup in the woofer's cone, which listening to these iQ3s is not bad,
but if it can be further reduced I may as well do so when upgrading the caps.
KEF have apparently upgraded the quality of the caps for the iQ30 also.
Does anyone here own iQ3, and can comment on the crossovers in their pair, and if they managed to get the pcbs out without damage to ?
Does anyone here own iQ30 and looked to see the values of the caps; inductors; resistors used in the crossovers of those ?
I saw it by chance about a month ago, but silly me did not take note of its Title or Starter.
Now I cannot find that Thread using Search - perhaps because Search will not accept the 3 letter words KEF and iQ3.
Does anyone here know how to find that Thread ?
Many of you will know that the driver in these KEFs is a Uni-Q , or UniQ as some abbreviate its spelling to,
but applying those in Search does not find it either !
The iQ3 pair I have here are a 2007 assembled pair -{the date is stamped inside the cabinet}-
and the crossover board there-in seems very difficult to remove.
It will probably have to have the tops of four nylon posts cut off, or the four corners of its pcb cut off to be able to get it out.
This version has 3 electrolytic caps, which I cannot see the uF printed on in the position they are on the pcb,
nor can I see the ohms of one of the resistors.
The second resistor is 6.8ohm.
There is a small 0.125mH air-core inductor, and a 1.1mH metal ccored inductor.
Both of those have labels stuck on them.
The sound of the treble is what one would expect after signal passing through two electrolytic caps,
and my guess is there is a 3rd order treble filter used.
I intend to replace these with polypropylene caps, and I probably will for the electro cap in the bass filter also.
I see that for the new KEF iQ30 that KEF state having lowered the crossover frequency from the 2.7kHz of the iQ3 to 2.5kHz for the iQ30.
My guess is that this is to reduce audibility of the upper midrange breakup in the woofer's cone, which listening to these iQ3s is not bad,
but if it can be further reduced I may as well do so when upgrading the caps.
KEF have apparently upgraded the quality of the caps for the iQ30 also.
Does anyone here own iQ3, and can comment on the crossovers in their pair, and if they managed to get the pcbs out without damage to ?
Does anyone here own iQ30 and looked to see the values of the caps; inductors; resistors used in the crossovers of those ?
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