KEF LS50 Wireless Active Speaker System Preview

[John Daddabbo]

Gene, If you have a moment would you mind elaborating on my concern? I currently use (in various rooms / setups) one of the following: an SVS AS-EQ1, or DSpeaker, or Behringer DCX2496, or MiniDSP, or the Audyssey XT32 built into my preamp processor. Yes, I own them all for I realized early on that in order to properly implement a Subwoofer(s) into my 2-Channel Audio system (or Home Theater alike) the need for both a Delay applied to the main speakers, as well as EQ applied to the Subwoofer frequencies

 

[John Daddabbo]

Perhaps your ears and measuring equipment are far more sensitive than mine. I'm still a neophyte and of the opinion that if it sounds good to me in my home that's all that matters.

Yes, I most heartedly agree with you! I would like to add one thought if I may. Although I do seem to have better than average hearing, what I wasn't born with was knowing How to listen and What to listen for. This only happen over many years of both reading such informative mags/sites such as Audioholics and from much practice, which included seeking out much better systems / setups than mine to Listen to so as to realize what I was missing (or simply not doing quite right). Yes, it is quite painful to Listen to systems in which the main speakers cost as much as my entire 2-Channel setup - preamp, amp, source, and speakers , however that approach proved quit helpful in the learning process. 35+ years in and I am still Learning... and improving my audio systems / setups. Happy Listening! (and Happy Holidays!)

 

[KEW]

Most subwoofers placed the same distance from the primary listening position will still exhibit a small amount of additional delay over the main speakers. And then of course the Phase control can only 'add' further delay to the Subwoofer, so therefore not fixing or even helping for that matter. Then there is the fact that an ideally placed Subwoofer is often not going to end up at the location of the main speakers, and instead often somewhat further away, and in this case a Delay applied to the main speakers is essential. Now, there are a few Subwoofers that exhibit a minimal amount of Latency (not to be confused with Group Delay), and for these few subwoofers one could place the subwoofer(s) slightly closer than the mains in order to correct for any small amount of Latency that the Subwoofer may have. Ideally placing the Subwoofer 'closer' (in a pure Timing sense) so that one could then use the Phase control on the Subwoofer in order to fine tune to the mains at the crossover point. But again, very few subwoofers exhibit very low Latency, and even for the Subwoofers that do, the ideal placement is likely to be away from the mains. As well I personally always implement two Subwoofers in order to improve things further (assuming careful placement of course) and in this setup a Delay will need to be applied to the main speakers, and then by way of Subwoofer placement and the Phase controls on each Subwoofer, things can be dialed-in to near perfection. I hope this helps explain where I was coming from. It need not be automated, and instead the sophisticated DSP already included in the LS50 Wireless should be able to include Digital Delay to the main speakers for very little cost, which would then allow implementing a Subwoofer with the LS50 Wireless every bit as good as the LS50 itself has been designed to be... which of course is exceptionally good

Okay, I see where you are coming from. In theory that all makes perfect sense and certainly appeals to the purist in me! However, I have to question how critical it really is.
I would ask you to disconnect all speakers except your subs and listen to some music you are very familiar with (so you know what else is happening even though you are only hearing the subs). IME, there is nothing in this content that is going to stand out if it arrives a few milliseconds late. I would also point out that the pro audio monitor/sub systems used in recording studios do not bother with timing of the sub (there may be some that do, but I have never seen one).
Certainly, I implement this feature on my AVR's that offer it, but I have set up plenty of "dumb" analog 2.2 systems (some with high quality speakers and subs) without ever noticing an issue. For me, when a sub sounds sloppy it is either not ending sounds quick enough or it is bloated at the lowest frequencies.
It may be that my ears are not as sensitive to this.
Give listening to your subs alone a shot (it is a good experience to understand what a sub does in any case). According to recording industry publications, "percussive attacks" occur at 4kHz, so that is where the immediacy of the attack from plucking a bass or a kick drum is perceived. For me that never made sense until I listened to subs by themselves.

 

[KEW]

Gene, If you have a moment would you mind elaborating on my concern? I currently use (in various rooms / setups) one of the following: an SVS AS-EQ1, or DSpeaker, or Behringer DCX2496, or MiniDSP, or the Audyssey XT32 built into my preamp processor. Yes, I own them all for I realized early on that in order to properly implement a Subwoofer(s) into my 2-Channel Audio system (or Home Theater alike) the need for both a Delay applied to the main speakers, as well as EQ applied to the Subwoofer frequencies

How did you incorporate your SVS AS-eq1 into your system?

 

[John Daddabbo]

Okay, I see where you are coming from. In theory that all makes perfect sense and certainly appeals to the purist in me! However, I have to question how critical it really is.
I would ask you to disconnect all speakers except your subs and listen to some music you are very familiar with (so you know what else is happening even though you are only hearing the subs). IME, there is nothing in this content that is going to stand out if it arrives a few milliseconds late. I would also point out that the pro audio monitor/sub systems used in recording studios do not bother with timing of the sub (there may be some that do, but I have never seen one).
Certainly, I implement this feature on my AVR's that offer it, but I have set up plenty of "dumb" analog 2.2 systems (some with high quality speakers and subs) without ever noticing an issue. For me, when a sub sounds sloppy it is either not ending sounds quick enough or it is bloated at the lowest frequencies.
It may be that my ears are not as sensitive to this.
Give listening to your subs alone a shot (it is a good experience to understand what a sub does in any case). According to recording industry publications, "percussive attacks" occur at 4kHz, so that is where the immediacy of the attack from plucking a bass or a kick drum is perceived. For me that never made sense until I listened to subs by themselves.

Yes, I do that quite often... Listening to only the Sub(s), as well as only the mains (full range and crossed over), and then both together. I have for many years implemented setups with only dual Subs in order to take advantage of everything that this has to offer, so Time Delay on the main speakers (as well each Sub) is a must, however to your point... I have found that many people seem to actually 'like' the Fattening of the Bass which occurs when the Subwoofer(s) is in fact a bit delayed as compared to the mains (often in setups where where the Subs are crossed over to meet the mains running Full range). I've heard more than one very expensive setup which had the Sub(s) either 1/2 Cycle or 1 Full Cycle delayed compared to the mains, and both the high-end audio store who sold the setup, as well the new owner felt everything sounded good (). And again, I've heard countless systems where the Sub(s) were clearly delayed compared to the main speakers (and often to each other) and the owners felt that their systems never sounded better (Fatter Bass ). So Yes, I guess that I tend to be a bit more sensitive to all of the above than most people (especially the ones who downright prefer the Fattening of the Bass ). Oh, and exactly - when the 'Feeling' of the Plucking of a Bass or a Kick drum isn't perceived to me to be 100% in line with what I am 'hearing' (coming as you say from the higher frequencies) this is exactly what I dislike (notice). However when these both are 100% in sync with each other (or close enough that these ears can't tell otherwise), I simply lose myself in the music (and I am no longer listening to an Audio System, but rather lost in the Music).

 

[John Daddabbo]

How did you incorporate your SVS AS-eq1 into your system?

I incorporated the SVS AS-EQ1 into a couple of different systems over the years, and in a few different configurations for each of those Systems. And I have used the AS-EQ1 in a System for which had no Speaker Delays of any kind, as well in Systems which had Speaker Delays but only delay for a single subwoofer, as well as I now own (and only very recently so the Games have just begun ) a preamp processor which has separate Volume / Distance / Phase / and EQ for each Subwoofer (previously I used the AS-EQ1 on a preamp processor that had Delay/Distance for a single Subwoofer in order to successfully implement two subwoofers). With my latest gear / setup (which fully supports two subs), I am looking at either the latest MiniDSP (96 khz) or the Xilica to help solve two changes to my latest setup, which is to now run 3 Subwoofers for both 2-Channel and Music Surround, as well as a 4th Subwoofer (well, 4th & 5th) specific to Movies/LFE (currently I run 2 Subwoofers for both 2-Channel and Music Surround, as well as a 3rd & 4th Subwoofer specific to Movies/LFE, however switching to more Musical sealed design subwoofers has required me to increase the # of subwoofers in order to maintain the same output at frequencies of 28 hz and below). Yes, I do love my Bass (but not Fattened ). Plus the dedicated LFE Subs (with dedicated volume control) allow for Movie explosions (think opening scene from Godzilla / Nuclear explosion) to literally blow away the audience, as well as keep my 2-Channel / Surround Sound music sounding its best (i.e. the extra 2 subwoofers turned off).

 

[John Daddabbo]

Yes, I do that quite often... Listening to only the Sub(s), as well as only the mains (full range and crossed over), and then both together. I have for many years implemented setups with only dual Subs in order to take advantage of everything that this has to offer, so Time Delay on the main speakers (as well each Sub) is a must, however to your point... I have found that many people seem to actually 'like' the Fattening of the Bass which occurs when the Subwoofer(s) is in fact a bit delayed as compared to the mains (often in setups where where the Subs are crossed over to meet the mains running Full range). I've heard more than one very expensive setup which had the Sub(s) either 1/2 Cycle or 1 Full Cycle delayed compared to the mains, and both the high-end audio store who sold the setup, as well the new owner felt everything sounded good (). And again, I've heard countless systems where the Sub(s) were clearly delayed compared to the main speakers (and often to each other) and the owners felt that their systems never sounded better (Fatter Bass ). So Yes, I guess that I tend to be a bit more sensitive to all of the above than most people (especially the ones who downright prefer the Fattening of the Bass ). Oh, and exactly - when the 'Feeling' of the Plucking of a Bass or a Kick drum isn't perceived to me to be 100% in line with what I am 'hearing' (coming as you say from the higher frequencies) this is exactly what I dislike (notice). However when these both are 100% in sync with each other (or close enough that these ears can't tell otherwise), I simply lose myself in the music (and I am no longer listening to an Audio System, but rather lost in the Music).

For example: If I go into my preamp processor and either add or subtract 3 ft from the Subwoofer, I both hear a change, as well don't prefer the change. Or if I instead add or subtract 3 ft from either one of my two Subwoofers (instead as above to both and relative to the mains) I hear an even greater overall change, as well as one I most definitely do not prefer. Isn't this a Test that most should be able to duplicate assuming that their preamp processor has separate Distance settings for two Subwoofers (and they get the two Subwoofers time aligned correctly in the first place)? And when folks do, are they hearing a difference (if not, try 6 ft instead of 3 ft)? And when hearing the difference, do folks tend to like it better or worse? I can't imagine anyone preferring the Subwoofer(s) not time aligned with the main speakers, where as two subwoofers not time aligned with each other (Fattening of the Bass) I already know from experience that a surprising number of folks do in fact prefer this.

 

[KEW]

For example: If I go into my preamp processor and either add or subtract 3 ft from the Subwoofer, I both hear a change, as well don't prefer the change. Or if I instead add or subtract 3 ft from either one of my two Subwoofers (instead as above to both and relative to the mains) I hear an even greater overall change, as well as one I most definitely do not prefer. Isn't this a Test that most should be able to duplicate assuming that their preamp processor has separate Distance settings for two Subwoofers (and they get the two Subwoofers time aligned correctly in the first place)? And when folks do, are they hearing a difference (if not, try 6 ft instead of 3 ft)? And when hearing the difference, do folks tend to like it better or worse? I can't imagine anyone preferring the Subwoofer(s) not time aligned with the main speakers, where as two subwoofers not time aligned with each other (Fattening of the Bass) I already know from experience that a surprising number of folks do in fact prefer this.

It sounds like you do have an unusual ability. It may be the case that we would all hear the difference if we were able to A-B it (as in instantly switch between the two conditions). However, it sounds as if you have the ability to hear one, wait 15 seconds while switching the distance then hear the second condition and discern the difference. Actually it sound like you may be able to know if it is off without a reference for audio memory.

So what subs have you heard? Which worked for you and which were "fails"?

 

[John Daddabbo]

It sounds like you do have an unusual ability. It may be the case that we would all hear the difference if we were able to A-B it (as in instantly switch between the two conditions). However, it sounds as if you have the ability to hear one, wait 15 seconds while switching the distance then hear the second condition and discern the difference. Actually it sound like you may be able to know if it is off without a reference for audio memory.

So what subs have you heard? Which worked for you and which were "fails"?

I have only owned the HSU HRSW-12Va (my first), Polk Audio PSW-10 (ran 2 pairs of them / 4 in total with a B&W bookshelf speaker), a pair of SVS CS-ULTRA w/Samson 600 watts rms @ 4ohms plus Rane PE-15 parametric EQ), and a pair of SVS PC13 Ultra. All of them have worked quite well for me, but at the same time none of them have Nailed-it for me. That said, I plan to go Sealed this time around. I have narrowed it down to HSU ULS-15 mk2 (quad), GoldenEar XXL (pair), SVS SB16-ULTRA (pair).

 

[John Daddabbo]

It sounds like you do have an unusual ability. It may be the case that we would all hear the difference if we were able to A-B it (as in instantly switch between the two conditions). However, it sounds as if you have the ability to hear one, wait 15 seconds while switching the distance then hear the second condition and discern the difference. Actually it sound like you may be able to know if it is off without a reference for audio memory.

So what subs have you heard? Which worked for you and which were "fails"?

Good idea... Let me configure -6 ft., 0 ft., +6 ft. and have my wife randomly choose between the three (and recording her choice), and then I'll give a Listen at some point that day. We'll repeat this twice per day, for three days, and I'll request that my wife choose each setup at least once over the 3 days / 6 selections. And to be fair to me, the music of choice will be the Remastered version of Rush's Permanent Waves (for which I know and Love).

 

[KEW]

Good idea... Let me configure -6 ft., 0 ft., +6 ft. and have my wife randomly choose between the three (and recording her choice), and then I'll give a Listen at some point that day. We'll repeat this twice per day, for three days, and I'll request that my wife choose each setup at least once over the 3 days / 6 selections. And to be fair to me, the music of choice will be the Remastered version of Rush's Permanent Waves (for which I know and Love).

I like it!
I don't know if it is an option, but it is best if your wife doesn't have a clue what it is about so she doesn't give you any indications of whether you are guessing right or wrong.

 

[killdozzer]

KEF is doing this speaker the right way: incoming digital signal to DSP module that implements the crossover (plus equalization and subwoofer crossover as well) in the digital domain, then to two separate D-to-A converters and power amplifiers. A digital crossover has all kinds of advantages, as do separate amps directly coupled to (and tailored for) each driver.

Thanks. I've missed your answer the first time. So I was close enough; they have separate DA converters for tweeters and woofers. Separate amps are still widely debated, I'm leaving that one alone for now.

Digital crossovers having advantages is fine by me, but I do see a shitstorm on the horizon. It'll be like tubes and transistors all over again.

 

[John Daddabbo]

I like it!
I don't know if it is an option, but it is best if your wife doesn't have a clue what it is about so she doesn't give you any indications of whether you are guessing right or wrong.

Oh, no worries there for she doesn't want a clue and really could care less So yes, she will be making a choice for which she'll have no clue as to what difference it makes... Heck, no clue at all of what it is even about. However she does tend to let me do as I wish, so you'll get no complaints from this Husband.