Subwoofer standby tragedy

[Grateful Garret]

Hmm. It sounds like the line level signal to the sub is too low for it to stay on. Have you attempted to contact Kef and get their recommendations based on your setup? They may be more knowledgeable than the previous owner. There may be a setting you can adjust in the app. Also, you could try plugging both RCA subwoofer outs (assuming you are only using one) into the Kube to see if that helps with lower volume signals.

P.S. the seller is the electronics store I purchased them from. They are the ones who said to try the sub trim all the way up, which I did not ever have to do with the old SVS set up. I had gain at 50% on old set up and now at 100% these KEFS are turning off unless I have the volume high, which will kill my relationship with my significant other

 

[MCH]

Hey @Misterer I don't know how this Kef sub works, but what I have seen in my svs subs is that the signal sense just triggers high the enable pin of the power supply. If this is the case with your Kef, it would be easy to either bypass the auto sense or change it for a regular trigger input.
Again, I have no idea if your sub works like this, but it might be worth checking out if someone has posted a teardown somewhere.

 

[Grateful Garret]

Hey @Misterer I don't know how this Kef sub works, but what I have seen in my svs subs is that the signal sense just triggers high the enable pin of the power supply. If this is the case with your Kef, it would be easy to either bypass the auto sense or change it for a regular trigger input.
Again, I have no idea if your sub works like this, but it might be worth checking out if someone has posted a teardown somewhere.

Thank you, my friend, for the reply! Good news is that I am in the return period for these and that is what I am going to do. The new versions of this same sub have an always on feature (due no doubt, to the fact that others have had this issue). I will likely go with something else. My old SVS subs did not have this issue and the gain never needed to be turned up on the pre-amp.

 

[Chromatischism]

Different subs have different input sensitivity for the auto-on feature. You just need to use a higher input level and reduce gain on the sub. You can do that either through the processor or with a Y-cable.

If looking at other brands, I can vouch for Rythmik having a very high sensitivity.

 

[Grateful Garret]

Thank you for the reply. You are correct with the y-cable. I took one sub out into a y-cable then into the 2 inputs on the kef wi fi unit and that did the trick. Things seem to be working well and I didn’t have to go through the hell of returning things, thank goodness. I have it all dialed in and running smoothly now.

 

[Dimitrie]

I’ve been looking for a solution for some time. The only thing that worked for me was to use the high level from amp and use resistors to lower the voltage to a ok value for rca inputs until the subs started playing even at low volumes. Initialy i had to crank up the volume to -35db now it wakes up at -60db. Very happy with the solution. The advantage is that using high level i’m preserving the sound signature of the amp and have a better integration with the speakers. Also the resistors don’t degrade the signal like when you crank up the gain in the dsp/av receiver. I use two kube 10b in stereo mode. For multi channel home theater users this is not applicable. This is a diy solution so be careful when doing this. Also you can try a high level to low level adapter like from svs but it does not provide adjustments for how high you will get the output signal.

 

[Redacted]

If the subs are connected to pre-amp out channels, they are more likely to trigger 'on' than if they are on filtered, dedicated sub channels (the subs do their own filtering usually)
But you may find it is easier to set a slightly higher start up volume and turn it down than changing tracks.