How to do a highend DIY loudspeaker with Kef:s uniQ driver ?

[Tangband]

This is the reason you must crossover a uniQ driver at 200 Hz or higher , If playing very loud bass tones , theres gonna be a frequency modulation at 7000-8000 Hz that is 8 dB in amplitude.

 

[fluid]

Thanks !
So your conlusion is that 30 cm wide baffle is good enough for most rooms, the reach down to the schroeder /transition area ?

On the face of it to exert some control over directivity in the transition region then yes it is.

It isn't just the width that determines the shape and frequency of these directivity effects, but the depth and edge treatment of both the front and back corners of the box. This quickly becomes quite complicated as reality tends to be.

Above as an example, this is the difference in a horizontal normalized polar between a 200mm and 400mm depth of cabinet, both have a 200mm wide baffle. The Linton shown above is about as deep as it is wide which is why the directivity has that single null at 150Hz. The diffraction from the back corners of the box is creating a mild super cardioid pattern. You can see it in this observation field at 400Hz.

The wider the box is in comparison to it's depth the more that effect is created. The deeper it is compared to the width the more it is supressed. Deep boxes and sharp corners push the main diffraction hump down in frequency but give more overall ripple.

Then the field looks like this in comparison at 400Hz

 

[Reigningchamp]

On the face of it to exert some control over directivity in the transition region then yes it is.

It isn't just the width that determines the shape and frequency of these directivity effects, but the depth and edge treatment of both the front and back corners of the box. This quickly becomes quite complicated as reality tends to be.

Above as an example, this is the difference in a horizontal normalized polar between a 200mm and 400mm depth of cabinet, both have a 200mm wide baffle. The Linton shown above is about as deep as it is wide which is why the directivity has that single null at 150Hz. The diffraction from the back corners of the box is creating a mild super cardioid pattern. You can see it in this observation field at 400Hz.

The wider the box is in comparison to it's depth the more that effect is created. The deeper it is compared to the width the more it is supressed. Deep boxes and sharp corners push the main diffraction hump down in frequency but give more overall ripple.

Then the field looks like this in comparison at 400Hz

Can I ask what software you use to make these plots?

 

[fluid]

Can I ask what software you use to make these plots?

ABEC and VACS, although AKABAK is the current product. The author is kind enough to grant student licences for non commercial use.
http://www.randteam.de/

 

[Alex1022000]

Hi there.

i have build a speaker like a blade or more like a big ls60.
Kef uniq from r-series with 4x8inch woofers each.
Hypex Plate Amp.
LR4 Crossovers at I think it was 400Hz and 2950Hz and some minor eq in midrange.

3-way floorstanding with KEF coax (active)

Hello there, after reading for months i decided to make my self finally an account, because now its time and i need ur support. i am 22 years old, computer science student from germany. Until now i have always build either kits or subwoofers calculated with winisd. i have a umik1 for measuring...

www.diyaudio.com

 

[Tangband]

Hi there.

i have build a speaker like a blade or more like a big ls60.
Kef uniq from r-series with 4x8inch woofers each.
Hypex Plate Amp.
LR4 Crossovers at I think it was 400Hz and 2950Hz and some minor eq in midrange.

3-way floorstanding with KEF coax (active)

Hello there, after reading for months i decided to make my self finally an account, because now its time and i need ur support. i am 22 years old, computer science student from germany. Until now i have always build either kits or subwoofers calculated with winisd. i have a umik1 for measuring...

www.diyaudio.com

View attachment 228576

They look like a ls70 ! Very nice.

 

[valerianf]

"It seems all those drivers might have been developed for midrange use"
A long time ago, my center speaker was equipped with only one UNI Q driver.
It was a Kef Model 90 center.
Treble and higher mid-range frequencies were beautiful, but the lower mid-range was lacking.
I tried to modify the passive cross-over without success.
The UNI-Q driver alone was not going low enough in frequency and did not have a sufficient SPL level to match the other speakers.

 

[SomeDude]

Hello,

I also have DIY Speakers that use KEF coaxials that you might find interesting, in my case the ones from the LS50. They were not built by me but a fellow DIYer that wanted to get rid of them and I had a similar project planned so... :

They are each paired with two parallel Dayton Rs225-8 Woofers and an 18" OEM Subwoofer (x-max p-p of 50 mm 1800 W RMS Power rating).
It's currently in a semi active speaker configuration. I use Pulseaudio Crossover Rack on an MediaPC.That is my only source. I uses 24db/oct Linkwitz-Riley Filters. The lowest two octaves are handled by the subs, the Daytons play from 80 Hz to 360 Hz, higher frequencies go to the KEF coaxials, which have a passive crossover specifically designed for that baffle. There was a thread in a German DIY board about it but I can't find it. Some minor EQing is also applied.


Music is send via HDMI with 6 ch. PCM to a Denon AVR that I basically misuse as an Multi-Channel amp.

I did some off axis measurements but also can't find them. I like the speakers very much and I have been listening music and watching movies with them for about four years without touching the the initial settings.

I plan on dismantling the speakers and integrating the drivers into the walls of my new listening room.

Kind regards,

Michael