KEF XIO Technology Summary

[pthakkar24]

Hi all,

Thanks a lot for your interest in the new XIO Soundbar and the brand-new VECO Technology. As many of you have come to expect, we've prepared something similar to our usual whitepapers for XIO. However, we've taken a slightly different approach this time. Hence the new name.

We've intentionally made it more "lightweight" to appeal to a broader range of customers, including those who may not be familiar with the technical jargon, finer details of loudspeaker operation, and the engineering trajectory of the HiFi industry that many of you are accustomed to.

Here’s the link: https://assets.kef.com/product-support/xio-soundbars/KEF_XIO_Technology_Summary_20250709105426.pdf

For those interested in diving deeper into the new VECO Technology and what it brings to the table, I encourage you to check out the following videos by SoundStage!, where we explain exactly that in significant detail.

As always, I hope you enjoy learning about the new advancements and soon have a chance to experience the new product!

 

[kharan]

I'm quite curious as what you'll be able to achieve in a larger form factor.

Something like a future upgraded LS60, or an active R3 Meta.

 

[ppierre]

Thread 'KEF's Breakthrough VECO Speaker Technology to Lower Distortion–Explained by Its Inventors

 

[EERecordist]

I heard the original Philips motional feedback speaker at AES. I've been a fan of Velodyne. They are a small company so they dropped audio and focused on LIDAR for self-driving cars. I'm also a fan of Mackie's implementation. I think KEF is in a position to explore how low we can go with LF distortion. I'm not sure what our ears can here of it, maybe they can find a university to study that.

I'm also curious from the engineering team how ported vs non-ported plays with motional feedback.

 

[Vacceo]

It´s always a pleasure to listen to (and read) Dr. Oclee Brown, specially here. I can see this applied to subwoofers, and getting bigger subwoofers is never bad news.

 

[tktran303]

Dear Prathmesh,

Thanks for sharing.

Re:

"deeper bass with significantly reduced harmonic and intermodulation distortion, in the order of 15dB, over conventional small-box systems"

bold: my emphasis​

Q1: Are you allowed to show any data to support this assertion?

What about if the box was not small? eg. KEF Blade META - how much improvement do you get there?​

Re:

"This information is fed back to the amplifier in a negative feedback loop to pre-compensate for the non-linearities before the driving signal is applied to the driver terminals."

Q2
Is this done via analogue or digital?




best regards,
Thanh

 

[pthakkar24]

Hi Thanh,

"deeper bass with significantly reduced harmonic and intermodulation distortion, in the order of 15dB, over conventional small-box systems"

bold: my emphasis​

Q1: Are you allowed to show any data to support this assertion?

Yes, of course.

This is an image from the patent application. Conventional voltage amplifier compared to the VECO arrangement, which is a combination of an instantaneous velocity sensor and a current output amplifier. In future versions of VECO, we plan to incorporate more advanced feedback architectures to achieve even greater distortion reduction across the full operating range of the associated drivers.

What about if the box was not small? eg. KEF Blade META - how much improvement do you get there?​

This particular case has not been explicitly tested, so I am unable to provide a definitive answer at this stage. However, VECO not only linearises the velocity of the driver movement but also supplies a constant driving current that is independent of the driver’s impedance (minimises current-related distortion). Consequently, its advantages extend beyond the low-frequency, stiffness-controlled range (where enclosure size tends to have the greatest impact).

"This information is fed back to the amplifier in a negative feedback loop to pre-compensate for the non-linearities before the driving signal is applied to the driver terminals."

Q2
Is this done via analogue or digital?

It is done in the analogue domain. The negative feedback loop is part of the bespoke amplifier arrangement.

Hope this helps!

 

[Vacceo]

I'm quite curious as what you'll be able to achieve in a larger form factor.

Something like a future upgraded LS60, or an active R3 Meta.

LS50 actives (Wireless II to be precise) dig quite deep in the low frequency section for a speaker their size. That is quite evident if you compare the passives to the actives. I wonder if the implementation of VECO would allow to scratch some further down hz´s.

The LS60´s reach a lot deeper, even if the db´s are somewhat compromised. Same applies to the KC62 and to an extent, the KC92. I understand that physics are still there and the limitations are what they are. However, with the side woofers of the LS60 (or the Blades) and a 12 inch dual subwoofer KC style, I guess the results could be quite amazing.

 

[Berwhale]

Intrigued!

Special project for Mr. Button or something to do with Lotus?

 

[voodooless]

Intrigued!

View attachment 462719

Special project for Mr. Button or something to do with Lotus?

I think it just happens to be this book

As for the technology: no, it's not new, but as so often, it's not the technology that counts, but how it is implemented. And in this case, KEF has chosen to design a driver from the ground up around this, and therefore could optimize performance and production cost/effort significantly, making it still something innovative in my book. From the posted measurements, it seems to be quite effective. But obviously, with so little surface area, you should still not expect any magic from these soundbars in terms of bass performance.