Help Kef Sub not working

I’ve recently setup a 3.1 sound system for the tv and since connecting everything up I’ve found my sub isn’t working. It get power but no bass even when turned up to maximum volume. I thought it maybe a first fuse and removed the cover but unfortunately I can’t make out or see any fuses. If anyone can locate them on the photos below I’d be forever grateful. Also if anyone that has any suggestions that’d also be appreciated.





How is the sub connected to the rest of the system? Are you sure it’s getting an audio signal?

Yes but it’s very weak, the AV amp recognises it but nothing is happening. It’s connected with a RCA type plug from the AVs Sub pre out to the sub, strangely the sub has both left and right inputs

Are you using a single (mono) RCA lead from the LFE output on an AV amp? Most subs have a pair of stereo inputs to run them in an audio system where the bass comes from a stereo recording. Often one of these on the back of the sub also performs as an LFE (aka .1) input. Is that how you have it connected?

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You don’t say which model Kef sub you have, those I can find pictures of online all seem to have a mains inlet socket with the fuse in it, I think in a similar manner to Naim amps?
I think @ChrisSU is more likely right, it is the input you have used.

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You need a Y connector. Single Female to two male RCA’s

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Hi Pete, what model is it, I think I can make out a 10th March 2003 date on the circuit board in second to last picture at bottom left of the unit?

More than likely it’s a component failure within the power supply. If you aren’t comfortable diagnosing it yourself with a multimeter then I’d talk to your dealer. The two inputs are to allow it to be easily used singly in a stereo setup. Surround systems usually output a dedicated sub channel so you only need to use one.

Assuming the connection goes from an AV amp LFE output to the corresponding input on the sub, he needs a mono cable and no splitter.
Perhaps Pete will tell us the model of sub or post a photo instead of us guessing!

If the sub has an LFE input, is it switched to use it?

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