new KEF KC62 dual 6.5" subwoofer

[KMO]

The KC62 can only do its own crossover at line level - you would need to insert it between pre-amp and power-amp.

If you're using the high-level inputs to the sub, then there's no crossover, you would just be running in parallel, and set the sub's HPF to match the natural roll-off of the mains.

But if you've got an AVR receiver, you can tell it to do the crossover, and connect its SUBWOOFER PRE OUT to the sub's LFE LINE INPUT.

(Which Marantz AVR do you have, precisely? Then we can determine if it also has the DIRECT analogue crossover function I talked about above)

 

[Dennis_FL]

I have the Marantz 6013 (using for stereo only) and also have Emotiva external amps for the mains. I'm thinking down the road. I'd like to go from my DAC directly to the amp via XLR or RCA and eliminate the Marantz altogether. In that case I was trying to figure out how to have a crossover. I thought the sub provided that but I now see that's not so - unless I go unbalanced from the DAC to the sub first.

In each case I'd use Roon or the DAC for volume control.

But for now, I guess I'll wire the sub using the Marantz SUB OUT.

 

[KMO]

Okay, I can see the subwoofer setting in your manual

I'm hoping that means you get the analogue crossover in Direct mode. (Although the tie to LFE+Main I don't see in my Denon makes me wonder - is this a sub HPF only? Perhaps going digital to do it, so the mains remain analogue only, but it uses the ADC->DSP->DAC path for the sub? Or is the LFE+Main bit only related to "Stereo", not "Direct"?)

Otherwise, you engage the digital crossover by being in non-Direct mode with L/R set to "small".

 

[Dennis_FL]

I set it up for LFE+MAIN. I'd like to switch to High level later

Unfortunately, I got one of the subs that goes to sleep and doesn't wake up. Really frustrating. I'm going to see if Best Buy can do the upgrade

 

[Chrispy]

FFS are we still talking about his bass module (at best) as a sub?

 

[wwenze]

I set it up for LFE+MAIN. I'd like to switch to High level later

Unfortunately, I got one of the subs that goes to sleep and doesn't wake up. Really frustrating. I'm going to see if Best Buy can do the upgrade

Some subs need to be fed the original signal to stay awake. Because the LPF-ed signal has much lower amplitude compared to the original.

 

[Dennis_FL]

Some subs need to be fed the original signal to stay awake. Because the LPF-ed signal has much lower amplitude compared to the original.

There is a known issue with this sub and it has been fixed by KEF. I got one that hasn't been fixed. It needs to be either returned to KEF or maybe the Geeks can do it.

 

[KMO]

Unfortunately, I got one of the subs that goes to sleep and doesn't wake up. Really frustrating. I'm going to see if Best Buy can do the upgrade

If you're only running 2-channel (so don't have a real LFE signal), it should be fine to set the subwoofer level trim high on the receiver (and turn the volume down on the sub to compensate). Should help somewhat. Also using a Y-splitter and feeding input to both L+R may help - I've done that before with previous sleepy subs.

 

[KMO]

Oh, and I'm curious - DO you get an actual crossover in direct+subwoofer mode with your AVR? Or is it LPF only?

(If it's a crossover, difference should be visually obvious in the LS50 midwoofer. Hardly any motion with 80Hz HPF, compared to full-range).

 

[Dennis_FL]

I believe the MAIN speakers are full range.

 

[Dennis_FL]

A little choppy English, but here's the manual

 

[fcracer]

I picked up a white KC62 to pair with an NAD M33, but sadly had to return it after seven days. There are a number of issues I experienced:

• The KC62 won’t wake from sleep using the M33’s sub-out unless I increase the volumes to high levels. This is partially due to the M33’s low voltage output (max 1.1V) and the KC62’s wake threshold being too high (even their own KEF products struggle to wake the sub).
• There was a hum or ruffling sound from the subwoofer that would come and go. Changing the ground lift switch would sometimes fix the issue, only for it to reappear again randomly.
• When using the M33’s pre-outs, there was an ENORMOUS pop from the subwoofer when it would come out of sleep. This would be a full excursion movement of the woofer cones. The first time it happened, I’m certain it shortened my life by a few years. I posted a video of it on the KEF owner’s forum on Facebook if you’d like to see the incredible excursion of the little woofers.

The KC62 is a marvel of mechanical engineering, but it feels like a beta product. I’ll definitely be looking at the V2 version of this subwoofer, when all the kinks are worked out.

 

[KMO]

The number of problems reported on the KC62 seems bonkers. Because it SHOULD be already V2, at least for the whole DSP/amp platform.

My older KF92 is performing flawlessly, with none of these issues. Never heard the slightest hum or anything, even with ear up to it, never a pop, and it wakes and stays on fine.

At most it might fail to come on with turned-down general TV dialogue, when there wasn't enough bass content to really notice anyway.

And the KC62 looks like it's based on the same electronics platform. How did they fluff up the electronics while doing the marvellous mechanical engineering?

My only thought is that maybe it's not the same electronics platform, because maybe they needed to step up to a higher-powered DSP to do the extra processing magic for the UniCore, and they screwed up some of the porting work.

 

[nothingman]

Far be it from me to defend KEF, I think they have handled this extremely poorly, but a couple things:

The wake/remain-on and popping noise problems were both fixed earlier this year, really just months after the first units were delivered. KEF is offering warranty service to anyone with a unit that predates the fix. I can’t comment on the hum issue and whether that’s related.

As @fcracer notes, the M33 and other NAD sub outs like on the C658 are notorious for having trouble waking a sub due to low voltage. You couldn’t really ask for a worse combination than a M33 and an un-serviced KC62.

I get it, though. KEF released a pricey, tiny sub that was always going to be looked at with suspicion, and then they shot themselves in the foot by not delivering on basic quality control in the early units. Even worse, on their KEF Owners Group Facebook page they pretend the issue doesn’t exist and sporadically delete messages about it and ban users who inform others about the available warranty service (ask me how I know).

 

[Dennis_FL]

I just got mine two days ago and it doesn't wake up. I heard that some dealers can do the upgrade and spare the expensive shipping to KEF. I got mine at Best Buy and I'll call them today. Otherwise, I'll return it.

 

[nothingman]

You want to talk to KEF about where you can have it serviced locally. Best Buy are probably going to be useless. Or you return it and try one from a dealer who can assure you their current stock have the fix from the factory.

 

[Tokyo_John]

Oh wow, I got the crossover working from the miniDPS SHD with the KEF LS50 Metas and KC62, it is already sublime. The high/low pass frequency is presently set to 60 Hz...I played around with it, anything higher in the present room localizes the sub, but at 60 Hz and under the sub location disappears. Many reviewers have commented about how well the LS50 Meta sound when crossed over with a sub, and now I have heard it for myself. Wow!

I have the microphone ready and will start running Dirac Live and perturbing the system. This is going to be fun, since there is still a lot to gain in terms of compensating for room response.

 

[Dennis_FL]

You want to talk to KEF about where you can have it serviced locally. Best Buy are probably going to be useless. Or you return it and try one from a dealer who can assure you their current stock have the fix from the factory.

Do you know a dealer with a probability of later firmware? KEF, Crutchfield, Amazon, and others are out of stock. Music Direct has some

 

[nothingman]

Do you know a dealer with a probability of later firmware? KEF, Crutchfield, Amazon, and others are out of stock. Music Direct has some

Music Direct was my choice, and they’ve always gone above and beyond on equipment sales for me. They definitely have new stock and are aware of the issue. I’ll PM you a contact.

 

[Dennis_FL]

When I talked with KEF he claimed the stock will soon be replenished so I believed him and ordered from KEF Online store. But your recommendation at Music Direct has been noted. I have ordered from them in the past with excellent results. Thanks for the contact info….I will definitely use it in the future.