new KEF KC62 dual 6.5" subwoofer

[JustJones]

It was interesting to see Kef use what they called origami inspiration for the surrounds and today on the interview with Lars Risbo he talked about why the surrounds on the Purifi 6.5 looked funky was to I believe reduce distortion? Perhaps something similar going on here.

 

[AudioJester]

Am I interpreting it correctly that this thing also has some form of servo control?

 

[Laserjock]

The linearity "+/- 3dB" doesn't predict this. Here's a real contribution:

Ah, not sure what my brain was thinking. Thanks for that link. Didn’t realize there were several threads going.

 

[Laserjock]

Am I interpreting it correctly that this thing also has some form of servo control?

Different type, had to re-read it myself.

“To reduce total harmonic distortion (THD), KEF has included its Smart Distortion Control Technology in the KC62. Many subwoofers use an electromechanical sensor to monitor the driver’s position relative to the waveform of the input signal. When non-linear discrepancies occur, which is common at high excursion, the driver’s motion is limited to reduce distortion. By contrast, Uni-Core’s low voice-coil inductance allows the KC62 to use an analog current sensor to directly and instantaneously measure the current in the voice coil, which is much more accurate than an electromechanical sensor, thereby reducing THD up to 75 percent.”

 

[YSC]

I came across that and is really interested! but I kind of confused about it's high pass filter setting, can anyone tell me that if I connect the preamp to KEF sub -> RCA line out to some active speakers, is it for optimization I should use the volume on the KEF sub to level match with the active speakers, then overall listening level can be done in the preamp to treat the whole system with one knob only?

 

[Zvu]

Sure. At what level? Certainly not at the 105dB level on a separated line.

Couldn't agree more. I was pointing at the source for F3 at 11Hz data.

 

[YSC]

if it got XLR in and out would be perfect

 

[AdamG]

These various KEF mini magic sub threads would serve better combined, would they not? Mods, is that possible?

 

[F1308]

if it got XLR in and out would be perfect

I think perhaps they avoided them to push buyers into the wireless dongle...

https://eu.kef.com/products/kw1-wireless-subwoofer-adapter-kit

 

[Pdxwayne]

For around same price, the Paradigm Seismic 110 can do 100db at 20 Hz at less than 6% distortion. If indeed the KEF can only do 80db max at 20 Hz, I don't see how it will be worth it....

 

[FeddyLost]

A lot of this price is for small size.
I think for 1500 USD one can get a lot of subwoofer if size is not a problem.

 

[Pdxwayne]

A lot of this price is for small size.
I think for 1500 USD one can get a lot of subwoofer if size is not a problem.

The Paradigm Seismic 110 measurements:
13.5" × 13.75" × 12.5625"
About double the volume of KEF.

If I do my math right, it would takes 4 of those KEF to equal the Paradigm in 20 Hz output....So the KEF didn't do any miracles when considering size vs 20 Hz output.

 

[YSC]

A lot of this price is for small size.
I think for 1500 USD one can get a lot of subwoofer if size is not a problem.

small size with the design and high pass filter fits all I desire in the sub, if I got the money would get it with 4 XLR-> RCA cables to use with 8030C

 

[dfuller]

It seems this dual opposing sub thing is becoming popular lately. I'd only really seen it in a few studio speakers and occasionally HT subs until very recently...

 

[F1308]

For around same price, the Paradigm Seismic 110 can do 100db at 20 Hz at less than 6% distortion. If indeed the KEF can only do 80db max at 20 Hz, I don't see how it will be worth it....

View attachment 107775

If I hear music most of the time at less than 60dB, topping 75dB, should I worry about those numbers showing 80 dB at 20 Hz ?

 

[Pdxwayne]

If I hear music most of the time at less than 60dB, topping 75dB, should I worry about those numbers showing 80 dB at 20 Hz ?

I don't listen to that level. No fun.

My typical peaks are over 90+ dB, and I sit more than 9 ft away.

If you only listen to low volume, then your priority is different than mine. Unless you really lacking space, plenty of others much cheaper options out there for your listening level.

 

[YSC]

I don't listen to that level. No fun.

My typical peaks are over 90+ dB, and I sit more than 9 ft away.

If you only listen to low volume, then your priority is different than mine. Unless you really lacking space, plenty of others much cheaper options out there for your listening level.

well, this sub I think is exactly designed to guys like me who is very limited in space, for myself if not using this the only fitting sub would be the Genelec 7040A, which can't go below 30Hz

 

[Pdxwayne]

well, this sub I think is exactly designed to guys like me who is very limited in space, for myself if not using this the only fitting sub would be the Genelec 7040A , which can't go below 30Hz

The Genelec 7040A:
Height:16.1"Width:13.75"Depth:8.1"

I guess what you are lacking is depth?

The Paradigm Seismic 110:
H13.5" × W13.75" × D12.5625"
Do you have 4.4" of depth?

How would you face the KEF to not block either of the woofers?

 

[YSC]

The Genelec 7040A:
Height:16.1"Width:13.75"Depth:8.1"

I guess what you are lacking is depth?

The Paradigm Seismic 110:
H13.5" × W13.75" × D12.5625"
Do you have 4.4" of depth?

How would you face the KEF to not block either of the woofers?

Yes I am lacking depth as it’s under my desk with around 500mm space, I don’t wanna sacrifice my legroom or accidentally kick on the drivers... the sides isn’t obstructed as I can have one side of it having 1.5m of free space and another at least 20cm. So likely can move it sideways and optimise the response

 

[RJO]

I don't think this will perform at its intended specs; at best, it will be similar to my velodyne microvee sub intended for small rooms with bass-anemic speakers:

Velodyne Microvee Specifications:
● Drivers: One Active 6.5" (with 64 oz
Magnet), Two 6.5" Passive Radiators
● Amplifier: 1,000 Watts RMS
● MFR: 38 Hz - 120 Hz ± 3 dB
● Low Pass: 50 Hz - 200 Hz Adjustable
● Phase: 00 - 1800 Switchable
● Dimensions: 9" H x 9" W x 9.6" D
● Weight: 15 Pounds
● MSRP: $799 USA; White or Black

However, curious as to why this new KEF doubles the weight at 30lbs.