Kef LS50 Wireless 2 and KC62 suggested crossover presets values

What are exactly the crossover preset values that you find in the original Kef app on the Wireless 2?

If I understand good, they should be 70hz on the LS50 and 45hz on the KC62.
If so, why this big hole between 45 and 70 hz?
It’s possible to choose also the crossover filter kind in the app?

I have the normal Metas and the KC62 and wonder what are the suggested crossover
values that I should set on my amplifier output settings, which a Lyngdorf TDAI-3400.


I wrote somewhat of a basic crib sheet on this, of which pages two and three directly relate to your question re: ‘the hole’

In short, ‘the hole’ is necessary to provide a flat combined response. Set them too far apart you get a dip in combined response, set them too close and you get a bump. The app presets are a good starting point, because we cannot take into account the room for this, obviously.

In regards to what you should set in your system, I’d bump the preset frequencies up maybe 10-15Hz as a starting point. KC62 is flat well above where you would be sitting a crossover anyway (and FYI, the crossover dial on KC62 is a 4th order (-24dB/octave) Linkwitz-Riley filter. I’d probably start with a 2nd order BW filter for the HPF on your Lyngdorf if that’s an option. Just beware that you should only set a LPF once to the sub - either disable it on the Lyngdorf (if possible) and set KC62 to manual, or use the Lyngdorf LPF and set KC62 to LFE.m

Key thing you’re listening for is no obvious holes in the bass. Room acoustics and speaker/listening position can affect this.

When in LFE I can still use the normal RCA stereo to stereo cable on the KC62?

Yes, the in the Lyngdorf I can set LR or BW filters on speakers and subs.

So these scenarios are correct to begin?

  • Bump some dB on 10-15Hz in EQ
  • Set HPF with BW 2nd order at 70Hz
  • Set LPF with LR 4th order -24dB at 45Hz
  • LFE


  • Bump some dB on 10-15Hz in EQ
  • Set HPF with BW 2nd order at 70Hz
  • No LPF on the Lyngdorf
  • Manual
  • LPF on the KC62 at 45Hz

Please confirm or correct

I mean bump up the crossover frequencies of the presets up by 10-15Hz (so start from around 55 and 90Hz) as the LS50 Metas do not have the same bass extension as the actives (due to DSP etc). Only touch gain/dB to volume match the speakers and sub (this will need measurements and/or listening on your part).

Whether you go the manual or LFE setting route on KC62 is totally up to you, just don’t use two LPFs.

And yes, you can still use the stereo inputs when in LFE - LFE mode on our subs simply bypasses the onboard crossover.

Then, wanting to use the Lyngdorf filters:

Set LPF with LR 4th order at 55Hz
Set HPF with BW 2nd order at 90Hz
LFE on KC62

Should be a good starting point - now to play around with the frequencies because, as I say, I can’t account for your room.

This article on Wikipedia helps to explain why Linkwitz-Riley filters need to have the high-pass and low-pass filter 3 db points separated. In a nutshell, it is because they need to be aligned at the -6dB points.

Will the above stated adviced settings good also in case of active correction (i.e. RoomPerfect or Dirac Live)?

Or in such case I should use different settings?

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I just got the KC62 subwoofer with KW1 transmitter to add to my original KEF ls50w pair (not the ls50w II). Despite all efforts and all attempted help by KEF support, I have never got the original Connect app to work with the speaker, and at this point, never expect to. Since I have been using Roon, for the most part successfully, with the KEF ls50w, not having that app functionality has kind of been a non-issue. But now with the KC62 subwoofer, that has eliminated the LTE option on the subwoofer, so I went ahead and set up the subwoofer on manual, using the starting point suggested in your crossover “crib sheet”, i.e., low pass @ 45, high pass @ 70, and volume at 3 pm. You mentioned a number of times in the “crib sheet” to be sure if using manual switch on the subwoofer (as opposed to LTE), not to erroneously employ any additional filters in the chain. So I just was looking for confirmation (or not) that my KEF ls50w would not automatically be adding an unwanted high or low pass filter, as again, I’ve never made any prior speaker settings from the KEF app for that speake,r as I’ve never been able to get the app to work.