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Best SUB for KEF ls50 wireless II

o2so

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On a side note, can anyone confirm if you can use two subs with the LS50 Wireless 2 using the speaker sub out?
 

Kachda

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insider tip: Kef Kube 12b (better then SB2000)
Would you mind letting us know on what basis do you make this claim and also how are you an insider ?
 

dasdoing

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Would you mind letting us know on what basis do you make this claim and also how are you an insider ?

I am an insider because I own it, and the sub is not realy talked about "on the outside"; which is most probably their fault because their subs used to be garbage and they had the "genius" idea to name the new line close to that garbage ones

https://www.avsforum.com/threads/kef-kube-12b-12-dsp-subwoofer-review.2957306/page-2#post-60158027
https://www.audiosciencereview.com/...th-subwoofer-options.17066/page-4#post-625819
 

Matias

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I am an insider because I own it, and the sub is not realy talked about "on the outside"; which is most probably their fault because their subs used to be garbage and they had the "genius" idea to name the new line close to that garbage ones

https://www.avsforum.com/threads/kef-kube-12b-12-dsp-subwoofer-review.2957306/page-2#post-60158027
https://www.audiosciencereview.com/...th-subwoofer-options.17066/page-4#post-625819
Plus they are going to update their subs with this new Uni-Core tech that shares the magnet between opposing drivers, each with different coil diameters, so they can save space (and cost).

https://hifipig.com/kef-apply-uni-core-technology-for-subwoofer-and-speakers/

kef_Uni-Core_tech_hifi_news_jan_2021.jpg
 

Spinitch

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The KEF cube also have KW1 wireless kit. But with recent announcement of coming UniCore , waiting to see price performance. KEF subs are available in many countries where the other value subs are not.
 

ishnish7

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Hey guys, I'm extremely new to the audio scene but had bought my girlfriend a set of KEF LSX speakers for Christmas. She's a huge music fan and absolutely loves them in hed bedroom. I know she'd absolutely love a sub to go with the setup.

I, myself, however caught the bug and have gotten very emotionally invested in the LS50 wireless 2 speakers for my apartment. This thread has been extremely informative and I have been considering getting a sub for this set as well. However, it seems as though dual subs are what's going to make this setup perform the best it should. Being that there's only one sub out on the back of the master speaker, how else am I to incorporate a dual sub setup for these speakers?

Sorry for the long response as this is my first ever post. Very excited to be a part of this community!
 

Matias

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Hey guys, I'm extremely new to the audio scene but had bought my girlfriend a set of KEF LSX speakers for Christmas. She's a huge music fan and absolutely loves them in hed bedroom. I know she'd absolutely love a sub to go with the setup.

I, myself, however caught the bug and have gotten very emotionally invested in the LS50 wireless 2 speakers for my apartment. This thread has been extremely informative and I have been considering getting a sub for this set as well. However, it seems as though dual subs are what's going to make this setup perform the best it should. Being that there's only one sub out on the back of the master speaker, how else am I to incorporate a dual sub setup for these speakers?

Sorry for the long response as this is my first ever post. Very excited to be a part of this community!
KEF just released the tiny KC62 subwoofer to go with those in small places.
https://international.kef.com/products/kc62-subwoofer
 

ishnish7

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Right, which seems very cool, but I am under the impression that those values they advertise are somewhat exploitive or exaggerated. Also, from some reading, I've gathered that one sub with two force cancelling drivers does not substitute two subs.Lastly, that KC62 is very expensive. I have read many great things about the Rythmik L12 so I was gonna start out with one and then add another. My questions is if I'll be able to do that with the KEF ls50 wireless 2s. Since I only see the one sub-out on the back of the master speaker only.
 
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leonroy

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Right, which seems very cool, but I am under the impression that those values they advertise are somewhat exploitive or exaggerated. Also, from some reading, I've gathered that one sub with two force cancelling drivers does not substitute two subs.Lastly, that KC62 is very expensive. I have read many great things about the Rythmik L12 so I was gonna start out with one and then add another. My questions is if I'll be able to do that with the KEF ls50 wireless 2s. Since I only see the one sub-out on the back of the master speaker only.

KEF have some faults but exaggerating specs is not one of them. They're one of the few speaker makers who post representative numbers. The sub is expensive but it probably has decent class D circuitry unlike the poor quality components their previous Kube range had (causing them to fail after a few years of use).

As far as having two subs the LS50 Wireless II actually supports two subs - there's a dedicated sub output on each speaker.

If you have the LS50 Wireless 1 though you can daisy chain some subs. Daisy chaining basically means sub1 is connected as normal and sub2 is connected to sub1. It doesn't give you 'stereo' bass but bass is omni-directional. Rythmik mention it on their site:
Rythmik Audio • FAQ - Frequently asked questions
 

ishnish7

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KEF have some faults but exaggerating specs is not one of them. They're one of the few speaker makers who post representative numbers. The sub is expensive but it probably has decent class D circuitry unlike the poor quality components their previous Kube range had (causing them to fail after a few years of use).

As far as having two subs the LS50 Wireless II actually supports two subs - there's a dedicated sub output on each speaker.

If you have the LS50 Wireless 1 though you can daisy chain some subs. Daisy chaining basically means sub1 is connected as normal and sub2 is connected to sub1. It doesn't give you 'stereo' bass but bass is omni-directional. Rythmik mention it on their site:
Rythmik Audio • FAQ - Frequently asked questions
Thank you so much for your reply. I have had a very hard time getting any responses and don't wanna bother. But being really new to this, I'm full of questions.
Great to know that the wireless ii have a sub out for each speaker!
My next question was people highly recommend using DSP to get the most out of any subs. I'm wondering if this is something that should be done if I were to get the two Rythmik L12s. Or will the KEF app be able to help out with this? I think that's something that has been extremely hard to find answers on being that these aren't well documented as it is.

I'm wondering if I should invest in a miniDSP 2x4 because my living room in my apartment is awkward shaped with a sloping ceiling. I'm sure the acoustics are not going to be ideal here. Basically, is DSP going to be necessary for my situation? And if so, I'm assuming the KEF control app can't really help with getting the most out of these subs, but not positive on this.
 

zorak950

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I know I'm late to the party, but be careful about conflating the characteristics of the passive and active LS50. The DSP in the wireless versions increases extension and decreases distortion significantly compared to the information referenced earlier. There's also a hard limit on how high they can be crossed over since its internal amp is controlled by the KEF Connect app: it won't let you set a high pass above 120 Hz.
 

ishnish7

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I know I'm late to the party, but be careful about conflating the characteristics of the passive and active LS50. The DSP in the wireless versions increases extension and decreases distortion significantly compared to the information referenced earlier. There's also a hard limit on how high they can be crossed over since its internal amp is controlled by the KEF Connect app: it won't let you set a high pass above 120 Hz.

Thank you for your reply!
Yes! I have heard the exact same thing or at least noticed it on a lot of other threads and forums actually. Very good to know.

Can you expand on what you mean by the second statement? Are you saying that the kef connect app won't actually let you cross over above120hz? How do people get around this?
 

zorak950

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Can you expand on what you mean by the second statement? Are you saying that the kef connect app won't actually let you cross over above120hz? How do people get around this?
Well, if you want to get technical the actual "crossover" point depends on a few things, but the high pass value is what determines how low your speakers will (or, more to the point, won't) play, which if you have high distortion in those lower regions that you can't cut out would be an impediment. As I intimated in my previous post though, the LS50 Wireless didn't have the problems in the bass range that the passive LS50 did, and the newer versions are even better.

The short answer is you can't get around it, but it's not really an issue. You shouldn't have any worries crossing over the LS50 Wireless IIs with a sub at 100 Hz or even 80 Hz, which will eliminate the localization aspect of the problem.

That dispensed with, a more important consideration in determining whether you need more than one subwoofer is how you use your space: with some time, effort, and placement flexibility you can usually dial in a single unit pretty well if you only listen in one spot, but if you're going to be moving around or have multiple people listening you'll never get anything close to even bass response without at least two.
 
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ishnish7

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Well, if you want to get technical the actual "crossover" point depends on a few things, but the high pass value is what determines how low your speakers will (or, more to the point, won't) play, which if you have high distortion in those lower regions that you can't cut out would be an impediment. As I intimated in my previous post though, the LS50 Wireless didn't have the problems in the bass range that the passive LS50 did, and the newer versions are even better.

The short answer is you can't get around it, but it's not really an issue. You shouldn't have any worries crossing over the LS50 Wireless IIs with a sub at 100 Hz or even 80 Hz, which will eliminate the localization aspect of the problem.

That dispensed with, a more important consideration in determining whether you need more than one subwoofer is how you use your space: with some time, effort, and placement flexibility you can usually dial in a single unit pretty well if you only listen in one spot, but if you're going to be moving around or have multiple people listening you'll never get anything close to even bass response without at least two.
This was an extremely helpful and prompt reply! Thank you so much!
 

zorak950

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My next question was people highly recommend using DSP to get the most out of any subs. I'm wondering if this is something that should be done if I were to get the two Rythmik L12s. Or will the KEF app be able to help out with this? I think that's something that has been extremely hard to find answers on being that these aren't well documented as it is.

I'm wondering if I should invest in a miniDSP 2x4 because my living room in my apartment is awkward shaped with a sloping ceiling. I'm sure the acoustics are not going to be ideal here. Basically, is DSP going to be necessary for my situation? And if so, I'm assuming the KEF control app can't really help with getting the most out of these subs, but not positive on this.
I don't have access to the app, but from what documentation I can find it doesn't look like there's any comprehensive bass management controls. In-line DSP will almost certainly give you more there, but it will also add a little latency. I'd say start without it. The experts on these matters pretty much agree that messing with an equalizer should be the last step anyway, after you've gotten everything else right- it's best used for that last bit of fine tuning, not to compensate for a bad setup. Once you've got everything as good as you can make it if you're still not satisfied with the evenness of the bass response you can always add a DSP later to get it where you want- it won't be any more expensive or less convenient after the fact than it will be up front.

Unless you're in a financial situation where money is no object I would heartily recommend looking for excuses to spend less, not more. If you're the sort of person who snubs "good" in search of "better," the audiophile beast will happily swallow all the money you're willing to throw at it. Just remember that the end goal is to get a sound you love in a way that works for your lifestyle, not to chase the greatest equipment or- worse still- the approval of audio snobs.

Codicil: There's a certain fun incongruity to pairing a Rythmik with an LS50W2. Here you have a pair of wireless, DSP-fueled speakers built around the internet and streaming, controlled through an app on your phone with nothing to break up the smooth profile except the connection plugs. There you have a subwoofer with an analog amplifier, a dozen switches and knobs jutting out of it next to a giant heatsink. Like a beautiful Frankenstein's monster of high end audio past and future. :):oops::p:D
 
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ishnish7

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I don't have access to the app, but from what documentation I can find it doesn't look like there's any comprehensive bass management controls. In-line DSP will almost certainly give you more there, but it will also add a little latency. I'd say start without it. The experts on these matters pretty much agree that messing with an equalizer should be the last step anyway, after you've gotten everything else right- it's best used for that last bit of fine tuning, not to compensate for a bad setup. Once you've got everything as good as you can make it if you're still not satisfied with the evenness of the bass response you can always add a DSP later to get it where you want- it won't be any more expensive or less convenient after the fact than it will be up front.

Unless you're in a financial situation where money is no object I would heartily recommend looking for excuses to spend less, not more. If you're the sort of person who snubs "good" in search of "better," the audiophile beast will happily swallow all the money you're willing to throw at it. Just remember that the end goal is to get a sound you love in a way that works for your lifestyle, not to chase the greatest equipment or- worse still- the approval of audio snobs.

Codicil: There's a certain fun incongruity to pairing a Rythmik with an LS50W2. Here you have a pair of wireless, DSP-fueled speakers built around the internet and streaming, controlled through an app on your phone with nothing to break up the smooth profile except the connection plugs. There you have a subwoofer with an analog amplifier, a dozen switches and knobs jutting out of it next to a giant heatsink. Like a beautiful Frankenstein's monster of high end audio past and future. :):oops::p:D
Zorak I've really really appreciated your replies on this matter. It's been killing me to find an answer. Especially being such a noob to all of this. My biggest concern with DSP was exactly what you mentioned: latency. Diving further into this field, I've learned that you can end up throwing tons of money into it! So getting this type of advice truly does help. I found myself doing so much research that it practically convinced me I NEED to invest into DSP to begin with and all of the fancy gadgets that could help with he sound. So this has been a breath of fresh air.

Reading your last paragraph, it almost makes me consider the new svs sb1000 pro subs due to the built in dsp. I imagine that would help with latency a lot more since it's built in? And the price is amazing!
 

zorak950

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Reading your last paragraph, it almost makes me consider the new svs sb1000 pro subs due to the built in dsp. I imagine that would help with latency a lot more since it's built in? And the price is amazing!
Regarding latency, a couple things to think about. First, a DSP will introduce latency no matter where it is in the setup, which means it will create a signal delay differential unless it's controlling all the speakers in your array. Some preamps will let you compensate for this manually, but I don't think the KEF Connect app has those settings. That means unless you tear open your speakers and rewire them you're going to have an offset. This will be true whether the DSP is built into the sub or added later, so don't think there's any magic to buying a subwoofer with an internal DSP. Second, as long as the DSP (be it internal or external) has a latency of no more than a few milliseconds, I wouldn't worry about it. Think of it this way: sound travels 1.13 feet in a millisecond. If you've ever watched a live performance and one musician was more than five feet (or one and a half meters, if you're not from 'Murica) further away from you than another, you were experiencing over five milliseconds of latency in hearing that musician's instrument compared to the closer one. Realistically, moving your subwoofer to the far wall in a medium-sized room will introduce more latency than a nice fast DSP will. Is it a thing? Yes, absolutely, but as long as the numbers are very small it's not worth thinking about.

From a technical perspective there's nothing wrong with pairing a digital speaker to an analog sub; the Subwoofer Out on your speakers is analog, so it's not like you're losing anything on the input side. Choosing is just a matter of what options you want built into the sub. Connoisseurs will tell you that the SVS lineup isn't as well tuned for music as the Rythmiks, but which one you would pick in a blind test, or whether you'd think any differences were worth the extra money, nobody but you can say. This is a matter of opinion, but if you're asking for mine I'd say consider the quality of the sound coming out of the box before you consider how you might be able to change that sound with DSP.

Which subwoofer sounds best to you is- for better or worse- subjective. Is there a shop near you that demos subwoofers? It's worth listening to a few things; even if they're not the same subs you're considering you'll get some sense of generalities like how sealed vs ported behaves, what kind of aesthetics you can live with, how loud a given decibel level really sounds in the sub bass region, et cetera. You might even be able to hook up with the DSP controls for one of them so you can get a sense of how that works. If you can narrow it down to two or three choices the best test would be to buy all of them, try them in your space, and return the ones you like less. Whether you can afford the month or two you'll be out the money until the refund comes though is another matter.

A note of caution: while it's true that many subs- including the SVS line- have some form of DSP built in, don't think you're necessarily going to get the level of functionality from those DSPs that you would from a high-end dedicated DSP box and software. There's a reason that the DDRC-24 costs nearly as much as the entire SB-1000. Not all DSP hardware/software is created equal, so make sure you think about why you want a DSP and which features are important to you as well as understand what a product can and can't do. With those things in mind you're likely to make a better decision than if you just fixate on "does this sub have a DSP or not."
 
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ishnish7

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Regarding latency, a couple things to think about. First, a DSP will introduce latency no matter where it is in the setup, which means it will create a signal delay differential unless it's controlling all the speakers in your array. Some preamps will let you compensate for this manually, but I don't think the KEF Connect app has those settings. That means unless you tear open your speakers and rewire them you're going to have an offset. This will be true whether the DSP is built into the sub or added later, so don't think there's any magic to buying a subwoofer with an internal DSP. Second, as long as the DSP (be it internal or external) has a latency of no more than a few milliseconds, I wouldn't worry about it. Think of it this way: sound travels 1.13 feet in a millisecond. If you've ever watched a live performance and one musician was more than five feet (or one and a half meters, if you're not from 'Murica) further away from you than another, you were experiencing over five milliseconds of latency in hearing that musician's instrument compared to the closer one. Realistically, moving your subwoofer to the far wall in a medium-sized room will introduce more latency than a nice fast DSP will. Is it a thing? Yes, absolutely, but as long as the numbers are very small it's not worth thinking about.

From a technical perspective there's nothing wrong with pairing a digital speaker to an analog sub; the Subwoofer Out on your speakers is analog, so it's not like you're losing anything on the input side. Choosing is just a matter of what options you want built into the sub. Connoisseurs will tell you that the SVS lineup isn't as well tuned for music as the Rythmiks, but which one you would pick in a blind test, or whether you'd think any differences were worth the extra money, nobody but you can say. This is a matter of opinion, but if you're asking for mine I'd say consider the quality of the sound coming out of the box before you consider how you might be able to change that sound with DSP.

Which subwoofer sounds best to you is- for better or worse- subjective. Is there a shop near you that demos subwoofers? It's worth listening to a few things; even if they're not the same subs you're considering you'll get some sense of generalities like how sealed vs ported behaves, what kind of aesthetics you can live with, how loud a given decibel level really sounds in the sub bass region, et cetera. You might even be able to hook up with the DSP controls for one of them so you can get a sense of how that works. If you can narrow it down to two or three choices the best test would be to buy all of them, try them in your space, and return the ones you like less. Whether you can afford the month or two you'll be out the money until the refund comes though is another matter.

A note of caution: while it's true that many subs- including the SVS line- have some form of DSP built in, don't think you're necessarily going to get the level of functionality from those DSPs that you would from a high-end dedicated DSP box and software. There's a reason that the DDRC-24 costs nearly as much as the entire SB-1000. Not all DSP hardware/software is created equal, so make sure you think about why you want a DSP and which features are important to you as well as understand what a product can and can't do. With those things in mind you're likely to make a better decision than if you just fixate on "does this sub have a DSP or not."

Awesome reply! It seems my best bet is to actually get some real world listening in. But this is harder to do because I know the best buy near me has a Magnolia center but no way will they have Rythmiks. Still, getting an idea of how the sealed SVS subs play with music would in itself be a huge benefit for me. Being that this will mainly be for music, I still believe I will probably be extremely happy with Rythmiks over the SVS. I also do not think I'll be anywhere near as picky as most audiophiles.

I don't believe I've ever had a situation where I can discern any delays with music in any situation so I imagine I won't be extremely picky. It would have to be pretty obvious to any average Joe for me to consider some form of DSP I guess. I guess my best bet here is to 1) Get the KEFs, 2) get the subs, 3) placement of subs 4) from there, determine whether I need DSP or not.

I do understand that the DSP in the SVS would be nowhere near as good as the one from the miniDSP but I figured it's better to have some dsp than none from the Rythmiks. However, because of the slight delay, I guess I'm in a position where I need to determine getting the Rythmiks that would have no delay paired with the KEFs (but no dsp) or the SVS that would have a slight delay (but WITH dsp). Ugh, decisions.
 

zorak950

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I guess I'm in a position where I need to determine getting the Rythmiks that would have no delay paired with the KEFs (but no dsp) or the SVS that would have a slight delay (but WITH dsp). Ugh, decisions.
The latency is unlikely to be a bother in either case; I'd focus on sound quality. Bear in mind that the Rythmik does have a single analog PEQ, so with a bit of playing around you can correct at least one room mode without any extra hardware. The SVS has a tri-band PEQ; together with good room placement you will almost certainly be able to deal with all the large deviations, but it still won't give you the ultra-fine control of the miniDSP or the powerful automatic room correction of Dirac Live. On the other hand, the LS50W2s don't have that level of user-facing control either and you're happy with them- I doubt you'll need to have a finer EQ for your sub bass frequencies than you have on your main speakers.

That said, if you think you might want to go in on a great external DSP, there are a couple of reasons to consider avoiding a subwoofer with built in DSP. First, latency is cumulative: if you've got two DSPs in the signal path you're going to combine the delays of both and that could begin to be noticeable. Second, the more times you convert your signal between analog and digital the more distortion you'll introduce: you're doing it once inside the LS50W2s (digital to analog) and each DSP you introduce is going to do it twice more (from analog to digital and back to analog again)- one DSP is already three conversions, two is five. Neither of those things is likely to wreck your experience, but both are technically undesirable.
 
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goldenears

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I have an SVS sub and I'm very happy with it for both music and movies. Personally I'm not that convinced that subwoofers can be particularly "musical" anyway (as long as they have good frequency response), especially considering how insensitive our ears are to low frequencies and THD at low frequencies.

Honestly, I'd go with the cheapest out of Rhythmik or SVS sub. Both well-reviewed and measured and very popular. Kef subs are too expensive IMO, and personally I wouldn't trust them for reliability with active electronics after X300A and lots of stories about LS50W, but they may have improved.

Rhythmik was expensive/unavailable in my country so I sourced an SVS. Very happy with my decision.

I wouldn't worry about latency, they all have a phase dial so you can fix those problems. Room modes will be a bigger problem and will need to be mitigated by placement.

I believe the DSP on the LS50W and the sub are no competition for Dirac/Audyssey/etc. They won't correct a wonky room and AFAIK don't even have a mic to measure what's happening in-room.
 
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