To clarify i also consider the active KEF LS60 hence why also looking at matching subs.
The one drawback of the ls60 is that sub integration is somewhat lacking
The one drawback of the ls60 is that sub integration is somewhat lacking
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Has anybody heard the new KEF KF92 sub? What are your opinions?
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Why the insistence that the kf92 won't have "meaningful" output at 16 hz when people are measuring it flat to that in their rooms? When neighbors in houses next door complain about the earthquake shockwave? And some professional reviewers have praised it for its powerful deep extension below 20 once they got it in a room. Rattling windows, pictures falling off walls.. I mean, what does one want, beyond that, exactly, for output to be "meaningful?" It's like I've heard comments about the kc62 in that regard too: "we were all skeptical but once we actually hooked it up we realized that, yeah, this thing does go deep... can't get as loud deep as a good larger sub, but at normal listening levels in a medium room, it does go deep, below 20... and if you put two, well..." So there's this disconnect of expectation and reality, apparently, as a theme for these subs: they outperform their size and theoretically anticipated capabilities. You pay for that outperformance, but you get it. There may be some limitation as to how loud it ultimately will play, but unless you want extended rock concert levels in your living room, they will handle deep and pretty darn loud, louder than comfortable. At least, that's what almost all the owners of these products are reporting, ones who report, in addition to reviewers who actually use them in their rooms for a period of time, not just measure them in free space. I don't own them myself, so I cannot report on my own experience with them, but over and over I see users express delight in the sub-20 extension of the kf92.
KEF designs their products to work with rooms. Some speakers, including subs, work better in rooms than some others that seem to measure better in "lab" conditions. Just as a simple example, remember the original Bose 301, series 1. Perhaps not the most "audiophile" selection, but that's part of the point and is also illustrative; in anechoic or free-space outdoor measurements, probably not so good, but get 'em in a room and let their interaction happen, and they sound pretty darn good to most real world ears, my own included. I'm not saying Bose = KEF . But, I just saw an interview with a KEF representative and he specifically pointed out that that's what KEF has been doing from the start: designing their products for performance in real rooms. It's the end experience in a real world situation that ultimately matters, and lab tests, especially when done in a way that isn't even how the product was designed, like a subwoofer in free space, are not necessarily indicative of the in room performance and end experience, though lab tests should be one consideration. Free space measures are artificial. There, I've said it. They are convenient and easy to standardize as a methodology, but they are artificial. This reminds me of a debate I had here some time ago about the Klipsch Herey IV... "oh, well it doesn't measure well and it resonates, so it can't be good" , but it is good when you get it in an appropriate real room and set it up right... it interacts with the environment, not an anechoic chamber. The new RSL Speedwoofers have ports down low to the floor and in the back, so of course they're going to measure and perform differently in a room with walls and better, due to the design, than they measure in free space... as another example.
That all off my chest, lol, I myself do take into consideration measurements, as a general overview. So I appreciate the charts and such, but I'm thinking the charts don't tell the whole story, and certainly don't necessarily reflect end user measurements and overall user experience. They are interesting, though.
KEF designs their products to work with rooms. Some speakers, including subs, work better in rooms than some others that seem to measure better in "lab" conditions. Just as a simple example, remember the original Bose 301, series 1. Perhaps not the most "audiophile" selection, but that's part of the point and is also illustrative; in anechoic or free-space outdoor measurements, probably not so good, but get 'em in a room and let their interaction happen, and they sound pretty darn good to most real world ears, my own included. I'm not saying Bose = KEF . But, I just saw an interview with a KEF representative and he specifically pointed out that that's what KEF has been doing from the start: designing their products for performance in real rooms. It's the end experience in a real world situation that ultimately matters, and lab tests, especially when done in a way that isn't even how the product was designed, like a subwoofer in free space, are not necessarily indicative of the in room performance and end experience, though lab tests should be one consideration. Free space measures are artificial. There, I've said it. They are convenient and easy to standardize as a methodology, but they are artificial. This reminds me of a debate I had here some time ago about the Klipsch Herey IV... "oh, well it doesn't measure well and it resonates, so it can't be good" , but it is good when you get it in an appropriate real room and set it up right... it interacts with the environment, not an anechoic chamber. The new RSL Speedwoofers have ports down low to the floor and in the back, so of course they're going to measure and perform differently in a room with walls and better, due to the design, than they measure in free space... as another example.
That all off my chest, lol, I myself do take into consideration measurements, as a general overview. So I appreciate the charts and such, but I'm thinking the charts don't tell the whole story, and certainly don't necessarily reflect end user measurements and overall user experience. They are interesting, though.
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Would be interesting to see the same graphs for say 40hz, which would perhaps be a more meaningful (and audible) frequency for typical use
Full disclaimer: I'm obviously asking this because I think our products would then be plotted differently compared to most of the others, except JL Audio perhaps.
That's sort of what I was trying to convey with my comment. "meaningful output at 16hz" isn't a useful requirement for most people. So all of those people are perfectly happy with the KF92 because they don't need 16hz output that can be felt.
You mention "Normal listening levels in a medium room". You can't even hear 20hz in that situation, much less 16hz. You can barely hear 25hz. I am not trying to talk down the KF92, I am trying to explain that this focus on 20hz and below is a misunderstanding.
People think they need this, but if they were presented with a subwoofer reproducing 16 or 20hz cleanly at "normal listening levels", what would happen? Absolutely nothing, because they wouldn't be able to hear it.
They have ‘sub outs’ and there is a subwoofer integration page on the app, with pre configured options for all the KEF subs and custom options for OEM.
Keith
Yes but there are no distance/lantency settings.
Some more advanced subs have up to 8-12ms processing delay which would be 4 meter in the distance setting in an AVR ? Longer than my whole listening distance ?
The kef subs are said to have low latency and one can assume they work with the ls60 ?
Hence why I’m hesitant to other subs without external means .
If i buy passive speakers i get an mini dsp and be done
Vacceo
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I understand you perfectly. If I could afford them, I'd get a pair of Blades. I love good sound and I love Brancusi. Can I get similar performance for less? Sure! But as object, those are wonderful speakers.
I have the LS active + KEF sub combo. I'm super happy with the result but that is because the combination works fine in my room. In other room, perhaps not so much, so I agree further adjustment on the APP can only be a benefit.Yes but there are no distance/lantency settings.
Some more advanced subs have up to 8-12ms processing delay which would be 4 meter in the distance setting in an AVR ? Longer than my whole listening distance ?
The kef subs are said to have low latency and one can assume they work with the ls60 ?
Hence why I’m hesitant to other subs without external means .
If i buy passive speakers i get an mini dsp and be done
bo_knows
Addicted to Fun and Learning
This "When neighbors in houses next door complain about the earthquake shockwave?"
I was walking with my family one evening around the neighborhood and I heard this low-frequency rumble from the sub(s) across the street and almost a block away! I live in an upscale neighborhood with large homes (made out of wood structures, plywood, veneer bricks, and crapy windows) and wide streets. If I was his neighbor, I would talk to him/her first and if not corrected, call the cops every single time for disturbing the piece.
A great option is the kube 12b or the newer 12 MIE. I have the kube 12b and had for two weeks the kf92. The kube is only slighty bigger but the 12inch driver outclast the kf92 by a huge margin. It goes also down in my room to 10hz but can mantain it even on realy high volume. The kf92 falls fast and the limiter kick in. Also the bass has more body on the kube. For example the scene in jurrasic world one where the woman release the trex. The rumble that the gate do is much more impectfull on the kube. An other example was in the edge of tomorrow. In the opening scene is a part with infrasonic bass. This was a day and night differnet between them. Even iff i tried to volume up the kf92 it wasnt able to push more. For the testing i had both subs sode by side. And later both in the same spot. I also took messurements with rew and the umik, wich i can share at saturady as im current in holidays. I don t realy know why kef claims the kf92 do down to 11hz and the kube 12b only 22hz. I feel good amount at 19hz off pressure with kube, with the kef92 its arround 23/25hz, lower than that it lost nearly all power
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Vacceo
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On those cases, I´d start remodeling my house with passivehaus standards. Energy efficiency aside, they also have the advantage of sound isolation. Who knows, an amp on a relatively long listening session could be enough to heat up a room.
KC120! Dual 12´s on 1000 W amps. To be honest, it would be around the capabilities of an Arendal 1723 2S.
I think the name would be KC 122 (12inch x2)has on the kc62 means(6inch x 2) and on the kc92 (9inch x 2)
If you actually listen to Erin's entire review of the KF92 it pretty much echoes everything I have said in this thread, including his discussion of the standardized listening rooms used to establish THX certifications.
I hope people watch and listen carefully to everything he says instead of just looking at the graphs and numbers.
you should definitely buy a few. You're already convinced; no audio science necessary. Make sure to place them close and invert the phase on one to "balance" the unbalanced signal!
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The phase should only incert if one sub stands in the front and the other on the backwall. If not the bass will be cancel.
I jad already one kf92 and i jad similar experience to erin. The kf92 is a great sub for läplaying music but for movies it hasn t enough power even two are not enough. But i have an open 35qm livingroom. Two kube 12b did the best job for me to get the room shaked
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It does what it does. Measurements at uncalibrated SPL under who knows what conditions are not indicative of much, let alone dispositive of anything.
I understand where you’re coming from - internet audio people tend to vastly exaggerate the volume displacement “needed” for home use. But that’s a separate discussion from the relative or absolute merits of any one sub.
No, not really. The bases for comparison aren’t there.
No, not really. Those look like a fine value for what’s offered, though.
Was referring to this novel idea
XLR to RCA Subwoofer new idea?
I have been going back and forth with particularly subs with manageable weight and low extension. It seems like you can never get the perfect set of features. Some have XLR and some are more affordable but only have RCA. Assuming a XLR preamp or processor this is a dilemma. Spend thousands...
www.audiosciencereview.com
here's my report back on my REW measurements in my room, for the ELAC ds1000, the RSL 10s mk2, and... my old Pinnacle Baby Boomer for fun. My architecture and room layout limits positioning, but I did try a total of five slightly different positions. I currently do not have "room correction software" nor even digital bass management, and run speaker-level out from my Marantz Ruby amp and the subs' own low pass crossovers... because that's what I have. Probably, bumps and aberrations could be smoothed over with processing, I'm aware. But, here's my results, in my room, with my current gear.
I first measured my Q Acoustics Concept 50 without any sub... and was pleased to find, as reported by reviewers, that even in my imperfect room they are remarkably flat from 50-20,000. Stellar, I'd call it. Can't do much better. But, there is rapid rolloff under 50, and hence the sub(s).
Sum up: the ELAC ds1000 does measure "best" where I need it: under 50 hz, more like under 40. It is also tamest in its work above 50, interacting nicely, flatly, with my Q Acoustics Concept 50 and my room.
ELAC ds1000 has the smoothest response that I was able to achieve... I still have a bump up in about 40-50 with it, but not too bad and less than the other subs; the bumps will be due to crossover point, some overlap right in there. So far, the "parametric eq" app of the ELAC has not been able to smooth out the bump... indeed the app has proven to be virtually useless to achieve anything better than the simple "auto eq" set up of the ELAC... and I spent at least six hours on the ELAC alone, trying all sorts of different settings. Aside from the 40-50 bump, in its best position (which is slightly off-center, not exactly where I originally had it), it measures quite flat to 18hz, from which it rolls down but not off a cliff. The measurements were very useful in that I was able to see concrete visual results of small changes of position of the sub, as well as the gain setting, so I can get it more closer to the "ideal" position for performance and integration in the limitations of flexibility I currently have.
that said... at 1/5 the retail price of the ELAC, The RSL 10s mk2 is not far behind at all and I get down to 18 flat with it as well, but it does drop off more sharply lower after that. I don't care about lower than that, truthfully. It is the ELAC's almost (like really close, maybe 1db diff) equal at 20, 25, 30 etc... unfortunately, with my setup the RSL has a significant bump up in the region of about 70-100, a bump I cannot get rid of by turning down the gain because then I also lose the under-40hz response that I'm seeking. If I had correction processing, perhaps with a miniDSP type thing if not a new amp (lol), then I could tamp down that bump. If I could chop off the bump in that 70-100 region, the RSL would be a remarkable choice as it virtually matches the 5x more expensive ELAC, in my space. So, to the naysayers who think the RSL isn't up to task compared to a more expensive option, I say you're wrong, at least in my room. It is really flat, except for the regional bump. I also like how the RSL sounds, it's overall character: it is lively, crisp... maybe that's due to efficiency and the well-designed port. I totally get why people love it. In white with the heather grey grill, I also like the way it looks: understated, simple, casual, unobtrusive visually. I hate to return it, and I might not. Corrected and adjusted, two of them would really kick butt.
That's the problem with minimalist or "purist" analogue amp/gear: it limits one's flexibility in fixing problem spots; as is, the bump gives me an exaggerated bass response in that one region, and it's an exaggeration that I do hear and prefer not to have. Even the tone controls on the Marantz Ruby are baffling, as the bass centerpoint is 20hz...! Useless, for my needs! I'm tempted to ditch the Ruby for something like an Outlaw Audio receiver, which does have basic crossover management, even high pass... or tack on a Parasound 6 preamp and adjust low and high pass crossovers with it. Or add an AVR as a preamp to the Ruby, use the AVR's bass management, a Denon x4800 perhaps. It drives me crazy that the beauty after which I lust, the Technics su-r1000, failed to include even basic bass management and instead put their money into the fancy turntable correction for which I have zero interest or use. A miniDSP could though be used with the Technics, as it does have pre-out and in.
For fun, I also hooked up the old Pinnacle, Baby Boomer Plus... 8" dual-sided similar design to the SVS micro 3000. It's heavy and solid and I've always been impressed with its punchy quick response when paired with smaller speakers... however, my Q Acoustics Concept 50s are very capable down to 50. The Pinnacle's lowest crossover selection is 50... so, there's quite a bit of overlap and thus a bump. in the 40-50 region, the bump was similar to the ELAC's, but a little bit more up; in 70-100, the bump was more up, but less than the RSL... what unfortunately killed the Baby Boomer from this system though is that there is a large bumped up region from about 175-375hz, and so that is what I was hearing when I originally went on this new subwoofer quest. BUT, and this is "shocking" and gives the lie to the notion that small "lifestyle subs" must of necessity be lacking in the real world: in my space, aside from the aforementioned bumps, the Pinnacle measures flat to 18. That's right, it matches both the ELAC and the RSL at 20 and even 18hz. If only that exaggeration in the 175-350 range weren't there, and I had my druthers, and if it wasn't about 20 years old so I'm getting a slight amp hum out of it, I would use two of the Pinnacles and be done.
So... what now? What next? Keep running with that purist analogue Ruby integrated and live with the marginal 40-50hz ELAC bump, since everything else is darn flat? Or just bite the bullet and get something with which I could actually do some bass management...?
I first measured my Q Acoustics Concept 50 without any sub... and was pleased to find, as reported by reviewers, that even in my imperfect room they are remarkably flat from 50-20,000. Stellar, I'd call it. Can't do much better. But, there is rapid rolloff under 50, and hence the sub(s).
Sum up: the ELAC ds1000 does measure "best" where I need it: under 50 hz, more like under 40. It is also tamest in its work above 50, interacting nicely, flatly, with my Q Acoustics Concept 50 and my room.
ELAC ds1000 has the smoothest response that I was able to achieve... I still have a bump up in about 40-50 with it, but not too bad and less than the other subs; the bumps will be due to crossover point, some overlap right in there. So far, the "parametric eq" app of the ELAC has not been able to smooth out the bump... indeed the app has proven to be virtually useless to achieve anything better than the simple "auto eq" set up of the ELAC... and I spent at least six hours on the ELAC alone, trying all sorts of different settings. Aside from the 40-50 bump, in its best position (which is slightly off-center, not exactly where I originally had it), it measures quite flat to 18hz, from which it rolls down but not off a cliff. The measurements were very useful in that I was able to see concrete visual results of small changes of position of the sub, as well as the gain setting, so I can get it more closer to the "ideal" position for performance and integration in the limitations of flexibility I currently have.
that said... at 1/5 the retail price of the ELAC, The RSL 10s mk2 is not far behind at all and I get down to 18 flat with it as well, but it does drop off more sharply lower after that. I don't care about lower than that, truthfully. It is the ELAC's almost (like really close, maybe 1db diff) equal at 20, 25, 30 etc... unfortunately, with my setup the RSL has a significant bump up in the region of about 70-100, a bump I cannot get rid of by turning down the gain because then I also lose the under-40hz response that I'm seeking. If I had correction processing, perhaps with a miniDSP type thing if not a new amp (lol), then I could tamp down that bump. If I could chop off the bump in that 70-100 region, the RSL would be a remarkable choice as it virtually matches the 5x more expensive ELAC, in my space. So, to the naysayers who think the RSL isn't up to task compared to a more expensive option, I say you're wrong, at least in my room. It is really flat, except for the regional bump. I also like how the RSL sounds, it's overall character: it is lively, crisp... maybe that's due to efficiency and the well-designed port. I totally get why people love it. In white with the heather grey grill, I also like the way it looks: understated, simple, casual, unobtrusive visually. I hate to return it, and I might not. Corrected and adjusted, two of them would really kick butt.
That's the problem with minimalist or "purist" analogue amp/gear: it limits one's flexibility in fixing problem spots; as is, the bump gives me an exaggerated bass response in that one region, and it's an exaggeration that I do hear and prefer not to have. Even the tone controls on the Marantz Ruby are baffling, as the bass centerpoint is 20hz...! Useless, for my needs! I'm tempted to ditch the Ruby for something like an Outlaw Audio receiver, which does have basic crossover management, even high pass... or tack on a Parasound 6 preamp and adjust low and high pass crossovers with it. Or add an AVR as a preamp to the Ruby, use the AVR's bass management, a Denon x4800 perhaps. It drives me crazy that the beauty after which I lust, the Technics su-r1000, failed to include even basic bass management and instead put their money into the fancy turntable correction for which I have zero interest or use. A miniDSP could though be used with the Technics, as it does have pre-out and in.
For fun, I also hooked up the old Pinnacle, Baby Boomer Plus... 8" dual-sided similar design to the SVS micro 3000. It's heavy and solid and I've always been impressed with its punchy quick response when paired with smaller speakers... however, my Q Acoustics Concept 50s are very capable down to 50. The Pinnacle's lowest crossover selection is 50... so, there's quite a bit of overlap and thus a bump. in the 40-50 region, the bump was similar to the ELAC's, but a little bit more up; in 70-100, the bump was more up, but less than the RSL... what unfortunately killed the Baby Boomer from this system though is that there is a large bumped up region from about 175-375hz, and so that is what I was hearing when I originally went on this new subwoofer quest. BUT, and this is "shocking" and gives the lie to the notion that small "lifestyle subs" must of necessity be lacking in the real world: in my space, aside from the aforementioned bumps, the Pinnacle measures flat to 18. That's right, it matches both the ELAC and the RSL at 20 and even 18hz. If only that exaggeration in the 175-350 range weren't there, and I had my druthers, and if it wasn't about 20 years old so I'm getting a slight amp hum out of it, I would use two of the Pinnacles and be done.
So... what now? What next? Keep running with that purist analogue Ruby integrated and live with the marginal 40-50hz ELAC bump, since everything else is darn flat? Or just bite the bullet and get something with which I could actually do some bass management...?
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Aerial Acoustic Guy
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Hi All, Does anyone know the driver excursion (+/-) for the KC92 and/or KF92? Also does anyone have experience using 2 or 4 of these in a room? Thanks in advance.
Since someone revived this thread, I thought I'd insert a link to my own experience with the KC92 subs: https://www.stereophile.com/content/kef-kc92-powered-subwoofer.
Neuropsychology
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oh nice, hadn't seen that yet.
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