AH! It's one of the things I wanted to try but was stymied by lack of supply and extremely high price -- typically US$400 each + $100 shipping on ebay from HK. Way more than the ~US$650 I paid for my used pair of LS50 Meta. The enclosure is spiffy -- lots of great tech in there, quite hefty @ around 18 lbs.
Interestingly, I didn't notice for the first couple days that the rear ports had foam plugs in. When I took them out, the improvement in my environment was enormous. The sound had seemed a bit congested & small before but after the ports were opened, it became more expansive, open, with better illusion of bass. I'd guess the previous owner had them up against the wall.
At the moment, I have a couple of experimental enclosures than can be used as subs, and am working on a dedicated pair of stands, too. After testing with a single sub (with closed box 12" SB34SWNRX-S75-6 or Dayton 10" RSS265HF-8) and the 300W amp mentioned above, if it works out well, I'll consider putting the Daytons in 2 enclosures built as stands for the LS50 Meta. The fact that the Wiim sub output is mono is a bit unfortunate but probably not a big deal for this mostly TV media system if I cross at <150Hz.
The only way to use an external active crossover with the Wiim Amp Analog are line in or TOSLINK. The former is noisier & and the latter is somehow more of a pain in my experience. Plus the cost goes up & the easy eARC HDMI control isn't there...
https://assets.kef.com/product-support/r-series-meta/KEF_R_Series_with_MAT_WhitePaper_v2.pdf
I bought Q150 pair from discount sale a year ago, to make it 3.way. The project ceased because they found end user as is! diyaudio has at least two threas for Q150 mods.
I bought Q150 pair from discount sale a year ago, to make it 3.way. The project ceased because they found end user as is! diyaudio has at least two threas for Q150 mods.
Did the same....
The little KEF has little punch below 3-400Hz in larger rooms. So any woofer capable of going cleanly to 400Hz and down to where you wish or cross to subwoofers.... Should do. RS225 in closed boxes with two subwoofers, would be my minimum goal. Woofers on the picture is just the purifi and SB I happened to have laying around. LS50 Meta are now sold to my sister for her kitchen, and I use a dedicate KEF R version instead, with two WO24P and 4 subwoofers.
The little KEF has little punch below 3-400Hz in larger rooms. So any woofer capable of going cleanly to 400Hz and down to where you wish or cross to subwoofers.... Should do. RS225 in closed boxes with two subwoofers, would be my minimum goal. Woofers on the picture is just the purifi and SB I happened to have laying around. LS50 Meta are now sold to my sister for her kitchen, and I use a dedicate KEF R version instead, with two WO24P and 4 subwoofers.
Maybe I'm missing something but don't the LS50 Meta & the R series use the same "12th generation Uni-Q® driver array with MAT™ "? Hence the reference to "R series coax" is confusing. If you're referring to the whole speaker system and not just the driver, certainly it's easy to believe KEF would have done better with the pricier R series, but you're only using the coax driver, right?
Oh.. sorry for not being more precise.
I have the R series dedicated coax from a 2018 R3 speaker. It has a much flatter suspension than the driver in the LS50, which smooths out the response because of less obstructive interference and less xmax. The Z suspension which is necessary for the LS50 to have more xmax and deeper bass, require some compromises.
I'm biased... I know. And maybe it's mostly technical and measurable, and something you can hear. I just like to have the best technical solution for a given purpose, and I needed a dedicated midrange, not a midwoofer.
I have the R series dedicated coax from a 2018 R3 speaker. It has a much flatter suspension than the driver in the LS50, which smooths out the response because of less obstructive interference and less xmax. The Z suspension which is necessary for the LS50 to have more xmax and deeper bass, require some compromises.
I'm biased... I know. And maybe it's mostly technical and measurable, and something you can hear. I just like to have the best technical solution for a given purpose, and I needed a dedicated midrange, not a midwoofer.
digitalthor --
OK that makes more sense now.My targets for this system are less demanding than yours: It just need to be good enough -- ie, neutral balance, reasonably deep bass (at least flat to 40 Hz), maybe 100 dB peaks (at 1m), transparent enough to hear through to the original recording, dynamic within the <100 dB range, and easy to use/integrate with the TV as well as for music. With just the Wiim Amp & makeshift stands, the LS50 Meta is mostly there. I'll find out in a week or 2 whether a single mono sub with will take me all the way.
Single sub? Hmmm. Well maybe it can bring you something but i would bet on a few more to be way better.
Anyway, releasing this kind of coax from bass duty is most always beneficial ( ime it's always beneficial but some other members had different experience so it might not always be benificia, depend from your preferencesl).
The 1793 have different application than the R serie coax sure. It have more distortion in the 1/2khz region but at the same time the meta thingy really change it's sound with previous Ls50 serie ( for the better) and i would dare to say with non meta drivers in Kef's catalog. Directivity behaviour is different than R serie too but with a bit of work i'm sure a new 'ring'/waveguide profile could solve many things and make it on par with Rserie on this point.
All in all it's not a bad driver at all and open horizon to things a R could not do without being compromised too imho and from my own experience with it it's promising ( cardio).
I was a bit disapointed when i got it as i ordered an Rserie driver and got this one instead but now i spent a bit of time with i'm ok with it. The real downside for my preference is sd and sensibility which for my preference more or less limit it's use to circa 400hz as Digitalthor already pointed.
Too bad they don't make an 8" or 10" version with higher sensitivity, it could be an 'end of game' driver for me.
Anyway, releasing this kind of coax from bass duty is most always beneficial ( ime it's always beneficial but some other members had different experience so it might not always be benificia, depend from your preferencesl).
The 1793 have different application than the R serie coax sure. It have more distortion in the 1/2khz region but at the same time the meta thingy really change it's sound with previous Ls50 serie ( for the better) and i would dare to say with non meta drivers in Kef's catalog. Directivity behaviour is different than R serie too but with a bit of work i'm sure a new 'ring'/waveguide profile could solve many things and make it on par with Rserie on this point.
All in all it's not a bad driver at all and open horizon to things a R could not do without being compromised too imho and from my own experience with it it's promising ( cardio).
I was a bit disapointed when i got it as i ordered an Rserie driver and got this one instead but now i spent a bit of time with i'm ok with it. The real downside for my preference is sd and sensibility which for my preference more or less limit it's use to circa 400hz as Digitalthor already pointed.
Too bad they don't make an 8" or 10" version with higher sensitivity, it could be an 'end of game' driver for me.
Working on proper stands for the speakers. 25" tall posts mostly ready, made of fir milled from windfall tree here a few years ago, then kiln-dried. The center inset is recovered ipe (I think) trim from 2018 house renovation. They're quite heavy, I'm guessing ~10 kg each.
Got the stands done. 9.4 kg total weight. No time to apply finish yet. They look good so naturally I want say they sound better.😁
After an afternoon of comparing the LS50 Meta vs the Linkwitz Orions as a music-only + youtube + netflix conduit through the Wiim Amp and LG 65C3 TV, I am thoroughly conflicted.
The Orions have the big wide-open presentation I associate with dipole + deep natural bass of the 4 10" Peerless XLS woofers in H-config. They are very dynamic, detailed & can also play more comfortably louder. The KEFs, within a smaller tidier soundstage, are as involving after a few minutes of acclimatization, and especially for audio tracks in videos (movies, series), might have a bit of an edge. This edge is not enough because it's easy switch the PEQ in the miniDSP crossover to enhance speech intelligibility and reduce the bass a touch for TV/movies. I still haven't had time to complete suitable subs for the KEFs for a fairer match. This is all with the speakers about 7-8' apart, 2-3' from the wall behind the TV & speakers, and me sitting 9-10' away.
One thing is crystal clear: regardless of which speaker systems takes permanent stage in my LR, a control unit with eARC HDMI is an absolute MUST. Amazing how nice it is to have! A Wiim Ultimate might soon be in my future. 😉
The 2 speaker systems were actually run & controlled through the Wiim Amp -- the KEF in direct speaker output, and the Orions + miniDSP OpenDRC-DA8 via a Topping D10 connected to the USB output of the Wiim. Yeah, the Orions had the disadvantage of one extra component through which the signal passed but... they still came out ahead overall.
Gotta get those subs together!
The Orions have the big wide-open presentation I associate with dipole + deep natural bass of the 4 10" Peerless XLS woofers in H-config. They are very dynamic, detailed & can also play more comfortably louder. The KEFs, within a smaller tidier soundstage, are as involving after a few minutes of acclimatization, and especially for audio tracks in videos (movies, series), might have a bit of an edge. This edge is not enough because it's easy switch the PEQ in the miniDSP crossover to enhance speech intelligibility and reduce the bass a touch for TV/movies. I still haven't had time to complete suitable subs for the KEFs for a fairer match. This is all with the speakers about 7-8' apart, 2-3' from the wall behind the TV & speakers, and me sitting 9-10' away.
One thing is crystal clear: regardless of which speaker systems takes permanent stage in my LR, a control unit with eARC HDMI is an absolute MUST. Amazing how nice it is to have! A Wiim Ultimate might soon be in my future. 😉
The 2 speaker systems were actually run & controlled through the Wiim Amp -- the KEF in direct speaker output, and the Orions + miniDSP OpenDRC-DA8 via a Topping D10 connected to the USB output of the Wiim. Yeah, the Orions had the disadvantage of one extra component through which the signal passed but... they still came out ahead overall.
Gotta get those subs together!
Having spent some time perusing subwoofer options, I naturally stumbled across user reports and a few media reviews of the KEF K62 & K92 dual woofer force cancellation subs. There are other high performance subs, but few with the tiny size and technical sophistication of the these KEFs. Their claims suggest laws of physics have been seriously stretched: -3dB at 11Hz and 105 dB max out from a basketball size box with dual 6.5" drivers??? The drivers must have Purifi-like qualities and extreme EQ to achieve this. The air pressure in the little extruded aluminum boxes have to be intense!
I've used W-config open baffle woofers in a couple pairs of active dipoles & appreciate what dual opposed force cancellation can do, so I'm very interested in learning if anyone studied these KEF subs closely or thought about replicating them, at least for basic functionality if not the plethora of technical & interface features? Cloning one could be a fun project!
Any users of K62 or K92 -- or cancellation subs, DIY or not, please chime in.
I've used W-config open baffle woofers in a couple pairs of active dipoles & appreciate what dual opposed force cancellation can do, so I'm very interested in learning if anyone studied these KEF subs closely or thought about replicating them, at least for basic functionality if not the plethora of technical & interface features? Cloning one could be a fun project!
Any users of K62 or K92 -- or cancellation subs, DIY or not, please chime in.
I experimented with dual opposed sub: the 12" i talked about in previous post but with other smaller drivers too previously. In sealed box with LT ( my go to way of doing things).
There is not much to say about the principle if restricted to sub way imho, it works, box have almost zero vibration from panels even from smallish thickness.
The issue come from xover freq as the directivity behavior is not so nice as you go higher than 100hz in freq: the dual monopole configuration stay mostly omni below that freq with the 12" i've used ( box was 40cm depth, circa 30cm width and something like 65cm height). If you go higher there is compromise to be expected, 200hz being the limit on this point ime.
I've read people dislike the way it 'load' the room, i've not experienced this but they were mainly used as sub so, location and orientation doesn't really matter in this application.
This is what i'll implement with my four ways, but i'll have to find a better driver than the one i used ( cheap car sub drivers) as they had issue to me (their recommended high freq was 150hz and at 100hz for me it was too much already).
There is not much to say about the principle if restricted to sub way imho, it works, box have almost zero vibration from panels even from smallish thickness.
The issue come from xover freq as the directivity behavior is not so nice as you go higher than 100hz in freq: the dual monopole configuration stay mostly omni below that freq with the 12" i've used ( box was 40cm depth, circa 30cm width and something like 65cm height). If you go higher there is compromise to be expected, 200hz being the limit on this point ime.
I've read people dislike the way it 'load' the room, i've not experienced this but they were mainly used as sub so, location and orientation doesn't really matter in this application.
This is what i'll implement with my four ways, but i'll have to find a better driver than the one i used ( cheap car sub drivers) as they had issue to me (their recommended high freq was 150hz and at 100hz for me it was too much already).
Thanks for you comments, that's useful info, re higher frequencies. I am looking at more capable drivers. I still have some good 6.5" Seas aluminum cone drivers that might work in a tower config to use as stands for the LS50s. A no-vibes sub would be much better as a speaker stand, I'm sure.
Seems there are a lot of faulty PV1 subwoofers about for not a lot of money. I would assume bad electronics and the drivers are still good. Might be a way to get some drivers designed for the job at a decent price. You get 2 drivers with them.
Maybe in the UK. Not here in Canada. I see one listed on Canuck Audio Mart for CA$800. I do have some 6.5" Seas which sound and perform well; the only problem is they're not really meant for sub duty -- 12mm Xmax p-p.
You really don’t want a subwoofer per se, but a woofer module that can effectively handle midbass…..that’s the acoustic slam and air movement the little Ls50 lacks.
You’re a fan of OB bass right?…….continue with what you like…..you only need response to 200hz…..
Consider a slot loaded OB woofer module for each side like XRK built……..plenty of midbass impact. Use 4 8” woofers per side dual opposed
You’re a fan of OB bass right?…….continue with what you like…..you only need response to 200hz…..
Consider a slot loaded OB woofer module for each side like XRK built……..plenty of midbass impact. Use 4 8” woofers per side dual opposed