Adire Dakini (DDR) Modification

[Timn8ter]

Finally got these speakers in running order housed in very humble home built cabinets. Originally built per the published plans
http://www.adireaudio.com/Files/DDRDipoleDesign.pdf
I have added a pair of Linkwitz Dipole Woofer 2 to the bottom of each panel.
http://www.linkwitzlab.com/woofer2.htm
We're talking 4, yes count 'em, 4 Adire Shivas.
What I'm enjoying about this design, other than the sound of course, is I will continue to modify them over time. The MTM portion is still running with the original passive XO. This could easily be changed out for a fully active system. Also, I may want to try the replacement units for the Extremis whenever they become available. I would especially be interested if the cone material was something other than poly.
The low frequency sections are currently being powered by a Parts Express 250W plate amp, so while there are two bass sections they are currently mono, not stereo. This is temporary as I have a two-channel 4th order active crossover in the works.

[Timn8ter]

With the grill cover removed.

[Timn8ter]

A view of the back side.

[Timn8ter]

A little more info about these.
The upper panel is 3/4" birch ply with 1"x2"poplar trim. The bass portion is built per Linkwitz specs with 1/2 birch ply and 3/4" MDF and 1/4" x 2" poplar trim on top. The grill covers are made from 1/2" partical board.
The struts for the upper panel are supports for modular shelving sold at local home improvement stores and painted with Derusto textured.
The whole thing is coated with MinWax one step traditional maple stain. Gives it kindof an "antique" look.

[gtforme00]

I like these. Nice work you have done there. My desktop system is a pair of extemis matched with the old radioshack linaeum dipoles (both have equally low efficiency). Sitting just one meter away, I haven't needed a subwoofer yet. But maybe a small dipole bin would be in order to finish the mini DDR system out?

What frequency do you plan to set the woofer/sub-woofer transition at?

[Timn8ter]

Thanks.
Hard to imagine a subwoofer with Extremis based mains in a PC system. I was using a single vented Extremis bass box for a while with my PC system. Admittedly, my current PC speaker system is my Tang Band W3-871S/W5-704S with an Adire Koda10.
Overkill? Heh...
Anyway, I'm going to start with the high/low pass at 125Hz. The active XO will allow me to easily change this if I find it necessary. There are very few pieces of music that the Extremis cannot deal with at that XO point.

[gtforme00]

The extremis are in dipole on fairly small U baffles (9" widex4" deep). I am thinking about going with a wider baffle, maybe out of acrylic to reduce the visual impact. That would probably fix the urge to add a subwoofer.

These started as my college apartment speakers, and I never needed a subwoofer in the small room I had there. It was actually best to not have alot of bass because those small rooms really gave you alot of gain in the low frequencies. Now that I've moved on to bigger and better things (and rooms), the bass which once was not lacking has found need of enhancement.

Say, I haven't messed around with these in awhile. The DDR has a crossover frequency to the planar at 1.8kHz right? Do you find the midrange of the Extremis to be wanting at that low of a crossover point? I have mine crossed at 2.5k 4th order active if I recall. If Dan decided to cross the DDR at 1.8k 6th order, is there something I should be avoiding in the upper midrange?

Thanks!
David

[Timn8ter]

I think it's more of a tonality issue than one of frequency response with the Extremis. Measurement wise, you can run the Extremis up fairly high without encountering unacceptable peaks or dips. Personally, I wouldn't go any higher than 3kHz if you're using a 4th order or better XO. If you have a tweeter that can be crossed lower and still sound good I think you should definitely go with the lower XO point. The Extremis, for all it's virtues, is not a true mid-range driver and should not be treated like one.
I've used the Extremis in a couple of 3-way towers where my XO point to the mid-range was 400Hz. They are quite excellent in that type of application.

[arc2v]

Hey that looks good.

The DDRs were what started me on my DIY Dipole quest. I fell in love with the design just in time to find out you can't get the drivers anymore. Figures.

But I've been playing around with some other drivers trying to get a good fit. I was considering trying the dayton reference 5" MTM with the neo 3 and then using the RS 8" with a similar baffle design for the bass section. That won't get me much below 80Hz, though, so I'd still need a sub.

Another option is the same lower section, but using a Neo3 and Neo8 open baffle for the upper.

I like your idea of using a plate amp for the woofers. My biggest trouble so far has been level matching everything. I've been trying to do the whole thing passive 3 way.

Great work though! Those speakers look great!

[Timn8ter]

Thanks arc, I think the basic concept can be applied using an assortment of available drivers.
Good luck with your project!