Using KEF LS50 Wireless II with a Subwoofer

I have heard reports that using the workaround makes the bass sound horrible. I do know it wakes the sub almost immediately.

I recently acquired a mic and some software to see what some audio analysis may show; however, I am a complete neophyte as far as this is concerned. Any suggestions?

KEF LS50W version 1 user here paired with a couple of B&W ASW608 subwoofers (small, white, cheap especially at the bargain price I got them for, and intended to be a stopgap purchase until I worked out what I really wanted but are now well into year 3 of their residence in my living room). I would have upgraded to a pair of LS50W v2 plus matching stands and a pair of KC62 over a year ago now had it not been for this staying-in-standby mode so, if anyone from KEF is still monitoring these forums, that’s over £5K of revenue sitting on the sidelines from me alone just because of this one issue.

I probably won’t bother making serious efforts to find an alternative right now, aesthetics are also a key consideration for my household so small and white are essential properties plus I know already that the KEF50W is good and I am confident that the KC62 can outperform my B&W ASW608s (at least when they switch themselves on!) so I’ll carry on watching and waiting but I’m certainly not going through the hassle of upgrading and then potentially returning the KC62s until this standby issue is sorted out.

Obviously from this thread I know that there is a workaround that some people are satisfied with (although some are not) but come on KEF - the LS50W and KC62 are supposed to be a match made in heaven but they can’t even coordinate power-on/off properly without a workaround?

I really hope that rumour of a firmware fix for the LS50W is true (and a fix on the LS50W side makes makes sense, someone in this thread actually suggested that quite a while ago). If such a fix really isn’t possible then I hope that a KC62 v2 can resolve the issue even if the resolution is as crude as having an extra 3-way switch on the back for on/off/auto which is what my B&Ws have. In fairness my B&Ws also sometimes drop into standby when my LS50Ws are still playing but at least I can set the switches to on rather than auto and that forces them to stay on (24/7 if I forget to turn them off).

I believe there are enough KC62 owners with this problem for a proper class action lawsuit. It is insane that KEF has not formally addressed this, the sub is useless in LFE for anything with silent or low volume passages such as jazz, classical and movies. I trusted KEF will do the correct thing and kept mine long enough that I can no longer return it. Needless to say, Im angry.

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I had no prior experience with KEF, but expected a much more satisfactory solution to this defect.

Honestly surprised the sub passed quality control checks.

I’m running it with my LS50WIIs and KEF Connect app sub selection of KC62 with a +10dB gain.

The sub now comes On at lower volumes, and I timed a better than 15 minute period from when I shut Off the speakers, until the sub went into Standby.

So, it is working better. Maybe due to the recent LS50WII firmware update to Ver 2.3.

I wanted to have the sub facing me, but got tired of going over to the side to see if the orange Standby LED indicator was lit. Lol.

Maybe after some audio analysis with REW, I will turn the sub towards me.

Should I add KC62 to WII? Thanks

That’s entirely up to you. :slight_smile:

For me, the KC62 has filled out the LS50WII with a nice foundation resulting in a full range sound and a controlled, deep and pleasantly dry (as in: non blooming) bass that integrates well with the speakers.

Setting the subwoofer to manual mode, I have no problems at all waking the sub from sleep, even when playing music with modest bass at low volumes. So yes – I’m very happy with the combo.

I found KF92 open box for $1600. Do you think KF92 to big for WII? Thanks

Weird. Something wrong. Plugged my kc62 in. Seconds later it was thumping away with clean tight bass. Used the Kef Connect default crossover settings.

Works flawlessly.

A big big win for me

Neil, did you buy your KC62 recently? Nice that it works w default settings. I need to raise the sub gain by 16 dB with the KEF app just to wake it up.

I would like to face the sub driver toward me, but I like to keep an eye on the orange LED on the side that shows the sub has gone back to Standby.

My sub is working better now than it used to.

A bit late on my response. I have the KF92 working with the Kef LS50 Meta. A great match. Definitely not too big.

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Anyone observed differences between using cable connection to KC62 and kw1 adapter?
For me are big differences and I don’t know why. I am just changing between kw1 adapter and rca cable. no settings change in app, and the sub is much much better…
Sub is in LFE mode.
High frequency - 95
Low frequency - 55
Sub gain - 6

I noticed that the specs for the KW1 say this:



I checked the similar REL transmitter, the spec there says 16-20 msec, so the same range.

Given sound travels about 1 foot per msec, 17 msec equates to about 17 feet, this may be a factor in the sound quality.

I also note that Lyngdorf go to some lengths to enable time alignment of subwoofer/s with the main speakers, on products such as the TDAI-1120…

N.B. I don’t have any of the above products, just interested in what these products can do.

Have you tried testing the two configurations with a UMIK-1 and REW? That might reveal differences in frequency response that account for what you are hearing.

Came on this thread for a general peek around as I was considering getting a KC62. I’m shocked how inept this wake-up problem is, and the lack of action in fixing it. Why the hell doesn’t it just come out of standby whenever the connected KEF main speakers do, and go into standby when they do? Why would you ever want the mains playing without the connected sub?? I never want any component, no matter what it is, with an auto-off which I can’t override. This one is clearly causing big issues to many users who have paid a considerable sum for the sub, the lack of fix puts me off the whole idea of the Kef Wireless too, if I’m honest.

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Thanks very much for the heads-up, I hadn’t found this when I Googled whether the issue had been resolved earlier. Well, seems like I’m looking into this at the right time and this puts them firmly back on the radar. Really good KEF finally did the right thing.

Since this is no longer an issue, could I ask whether anyone has these working in a 5.1 setup (assuming one were to buy enough LS50IIs)? E.g., if I were to use a surround processor, can one feed the outputs to the digital inputs of the 50IIs, or has this got to be done in pairs, so L+R pair, Centre+Sub, RL+RR, etc. Or is there something precluding this kind of use?

James, I briefly looked into this when purchasing my LS50W2s and quickly concluded that operating LS50W2s in a 5.1 setup just isn’t a practical option and that there are better alternatives if you wish to go down that route. There are surround processors that will output digital signals in stereo pairs (FL, FR), (RL, RR), (CEN, SUB) so you could in principle get an input to each 5.1 channel provided you carefully selected the processor. But system controllability is a real challenge. How are you going to control the system’s volume, which basically needs to happen wirelessly using the speakers’ wireless platform? AFAIK you cannot group the speakers as a 5.1 system so the pairs of speakers will present as mutliple zones in the KF Connect App, Roon or whatever you are using (you can’t put a preamplifier upstream of the KEFs and use that to control volume). So you would need to adjust each pair’s volume individually, which is going to get very unwieldy! Same goes for EQ and tonal balance. The platform is just not designed to operate in a 5.1 format.

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The other point I should have made was that even if you were able to build a 5.1 system it will be the antithesis of anything “wireless”. Each speaker would need a power cable; each speaker would have an input cable. There would thus be double the number of cables that you’d have in a conventional passive setup! That might not be a concern for you but worth considering.