• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Keg R3 Meta -> R11 transplant

Daka

Senior Member
Joined
Oct 6, 2021
Messages
334
Likes
220
Does anyone with more technical knowledge if it’s possible to move Kef R3 Meta UniQ driver and crossover section to R11 (non-meta)?
R3 Meta has higher crossover at 420Hz/2.3kHz compared to R11 Metas at 330Hz/2.3kHz but at the same time old R11 has 400Hz/2.9kHz.
Reason being to save 1.5k in doing so whilst getting close to new Meta sound (yes there is a noticeable difference between R3 and R3 Meta).
 

MEGB1262

Member
Joined
Mar 27, 2022
Messages
30
Likes
33
Hi there,

i think this question is more something for the surgery experts of https://www.diyaudio.com/community/

I'm coming from the DIY corner and have made some positive experience with the full activation of the KEF midrange / tweeter chassis in self made cabinet with hypex plate amps

but this is a no go without measurement equipment like the Clio Pocket measurement system i am using

here some pics of my work, please do not stay with the criticism of the poor carpenter skills of mine, it was all made only for brief testing


HO-KEF-Cubes+Eggs-Capture.JPG12inch-WF-KEF-midrange-coax-Capture.JPG12inch-WF-KEF-midrange-coax-WCD-Capture.JPG

so far - so good, Stefano

P.S.:
there is a post here with the link to the new R series meta R & D whitepaper where you can see the list of improvements of the Uni-Q meta to the old Uni-Q chassis that i was able to buy years ago from a french internet shop as spare parts
but if you look at the wavelet cycle decay diagram with the active crossover it is already nearly free of mid range and high range frequency resonances without the meta stuff
please note the non rectangular cabinet approach of the standalone enclosure of the KEF chassis
KEF-DIY-Rear-Capture.JPGKEF-DIY-Front-Capture.JPG
 
Last edited:
OP
D

Daka

Senior Member
Joined
Oct 6, 2021
Messages
334
Likes
220
Impressive - but in this case I’m just want to swap out crossover plate and Uniq which are not that different - speaker size is remaining same so it seems on paper that no advanced speaker DYI knowledge is required. But I wonder if there is something I don’t know that would potentially be fatal here
 

MEGB1262

Member
Joined
Mar 27, 2022
Messages
30
Likes
33
Impressive - but in this case I’m just want to swap out crossover plate and Uniq which are not that different - speaker size is remaining same so it seems on paper that no advanced speaker DYI knowledge is required. But I wonder if there is something I don’t know that would potentially be fatal here
@Daka,

i am quite sure that crossover for the old Uni-Q will not fit perfectly for the new Uni-Q meta chassis

the wrong crossover for the Uni-Q chassis can ruin the whole swap approach

that said the approach to activate the whole stuff with hypex plate amps and find a DIY fellow with measurement equipment is even less risky

question: where do you get the meta chassis, you buy a new R3 meta and have the old R11 non meta already or the old R11 as used speakers?

oops, checked the specs of the R3 Meta against the R11, it cannot work with the swap of the crossover for sure!

the R11 has four bass chassis, R3 Meta only one

the sensitivity of the Uni-Q mid-high range chassis is attenuated much more to work with only one bass chassis in the small R3 meta cabinet


sensitivity difference over all 4 dB, 86db R3 Meta, 90 dB R11 - again this will not work with the crossover swap!

the showstopper:

r3meta nominal impedance 4 ohms
r11 nominal impedance 8 ohms
=> no way the crossover swap can match
for sure you have to completely rebuild the bass crossover section and to remove the attenuation of the mid section and high section of the crossover for the coax

there is a good chance to assume that the Uni-Q chassis for the R11 has a greater sensitivity as the Uni-Q chassis for the R3

to sort this out you have to find somebody that owns an R11 Meta and is willing to open it anyway

KEF use for sure a modified high tech Uni-Q chassis with neodymium magnet motor in the reference series and the blade, hard to find pics of those

last recommendation, buy the r3 meta and use two subwoofers to get the better bass performance

here the DIY fantasy kicks in again, build the subs on your own as floor stands for the r3 meta, e.g with 2 side mounted sw chassis for each floor stand sub for impulse compensation
 
Last edited:
OP
D

Daka

Senior Member
Joined
Oct 6, 2021
Messages
334
Likes
220
Old R11 to receive parts from new R3 meta. So you reckon there is difference in crossover section due to extra drivers?
This is more to do with new Dirac Art and I know subwoofers would be better but not keen to have 4 subs, I have two and that’s enough. So was thinking to add/change R3 to R11 that would support better ART as they should go as low as 30Hz
 

MaxwellsEq

Major Contributor
Forum Donor
Joined
Aug 18, 2020
Messages
1,839
Likes
2,802
Crossovers are designed to match the drivers to their cabinet. So it's extremely unlikely that what you propose will be a success.
 
Top Bottom