DIY-project: JBL Kebnekaise S4365

[1audiohack]

Kebnekaise 2.5

I like it! I am a two woofer kinda guy. 3.5 way or different sub?

Barry.

[bubbleboy76]

I like it! I am a two woofer kinda guy. 3.5 way or different sub?

Barry.

2.5 way. No sub, and no UHF, for now.

Anyone who knows how exactly the ".5" augmenting woofer in the Everest2 is setuped crossover-wise (acoustically)? Where it overlaps the other woofer, and how it rolls off.

Edit: Found some slopes here, but I do not know if it is electrical or acoustical target curves:
http://www.audioheritage.org/vbullet...l=1#post301424

[bubbleboy76]

Looks like an 6dB/oct rollof starting at 80Hz in the Everest2.

Page 15 here:
http://www.jblsynthesis.com/tl_files...s%20Manual.pdf

[bubbleboy76]

First create a rectangle(550x550), then push/extrude that into a block(838mm tall) then use the line tool to mark off the top/plan and the push tool to chop away the bits you dont want-think removal of material like a sculptor.

I got kind of that far. It is when trying to change things I get lost.

[1audiohack]

Looking at the measured response for the Lf woofer and its little board with two coils and caps makes me wonder.

I haven't looked for the component values yet but there is more to it than a coil.

Barry.

[bubbleboy76]

Maybe it is a kind of first-order Chebyschev-like electrical slope on LF1 in the Everest2?
Resulting in a first-order Bessel-like acoustical slope for LF1, with a bump down low compared to LF2.

[bubbleboy76]

Gives you an idea of proportions...

Thanks!

[bubbleboy76]

Current state of affairs.

[bubbleboy76]

I have sold the DBX4820, and I will use a BSS BLU-160 instead. The BSS is more flexible, and has in practice an unlimited number of PEQs to use per channel.

I have drycoded some initial settings for now, based on the ones I had for my active 4365.

[1audiohack]

Looking good!

Barry.

[bubbleboy76]

Looking good!

Barry.

Thanks

[bubbleboy76]

Finally, the build has started

Here you can see 3 sheets of 2x12mm mdf being glued with damping glue.

[bubbleboy76]

This is exactly how each LF-box will look like.

[1audiohack]

Is that a jack screw to press against the motor back plate?

Barry.

[bubbleboy76]

Yes.

It will also make it possible to connect to the back-wall, if I should want so in the future, to reduce rocking.

The boxes will have weightadjusted soft decoupling feet (I have hard floating wood floor).

Inside it is a 31mm diameter "machine foot" pressing against the element back. There is 51mm free radius on the back of the element, so it will not disturb the ventilation holes.