AE TD15M and SEOS15 (with DNA360)

I sold my big (bigger than Louis expected!) SEOS15+TD15M speakers today, with a promise that I'd do a passive crossover design for them. I had done a passive for them several years back, but wasn't entirely happy with it and switched to active before ever getting around to working the passive further.

Before the boxes went, we got fresh measurements on the woofer and tweeter in a bigger area and re-established the z offset for them. Then today, I did a new PCD design on them, which I'm sending to Louis. Thought I'd post it here, too, for any TD15M owners who want to go with a SEOS15 top. The design simulation came out very nice, phase response is unusually smooth (doesn't even roll over once through the band).


There's a PDF document here which has further data, schematic and Parts List: http://libinst.com/SEOS/SEOS15/SEOS15%20TD1M%20redo/TD15+SEOS15%20design.pdf

Hope this works for you Louis!

 

Much appreciated. Thank you!

 

Nice work bwaslo. What's the impedance of the speakers? Would this work for a sealed enclosure of about 3 cuft?

 

Hi Bill,

Thanks so much for creating and sharing this. I'm using your minidsp config now, but I would like to go passive for the sake of system simplicity.

My td15m (8ohm) and seos15 are separated by 1/4" (edge to edge), and recessed flush into my 19-3/8" wide baffle, in a 3ft3 sealed box. Does my speaker have any critical deviations from your design params?

Thanks!
-Max

 

Hi Max,
That should work.

Bill

 

donivan,

The impedance is 8 ohms or more over most of the audio band, but dips to 4.7 ohms in a range around 1kHz (an 8 ohm receiver should do fine with it).

Bill

 

Thanks Bill. So 8 ohm drivers for both the DNA360 (which I just noticed only comes in 8 ohm) and the td15m.


Max, how are you liking your td15m/seos 15? I"m thinking of going with that setup for home theater also in 3 cuft.

 

Thanks Bill.

donivan, I've only finished the center so far. I am using with Econowave SR speakers L and R. Since I haven't measured the new speaker yet, I'll just give you my sighted, audiophile-speak impressions. I really like my Econowaves SRs -- they are clear, dynamic, and the driver integration seems excellent. Unlike other horn speakers, I don't hear the difference between the horn and woofer -- it just all sounds "integrated". The SEOS has all of those nice properties as well. The SRs occasionally sound a bit "edgy", and my SEOS speaker never gets "edgy" -- it is always very comfortable to listen to. My SEOS speaker also seems to have "weightier, more textured" bass (I know, silly words). I measured my SRs and found that the bass starts to trail off a bit below 200Hz, so maybe the SEOS speakers don't do that and that's what I'm hearing (or my SR measurement experience is triggering a placebo effect ).


Making the center has me really itching to make the L&R so that I can hear them for music. But I'm still a bit undecided about the cabinets and I've been busy with other projects, so I haven't gotten around to building the L&R yet. I think about how nice it will be to hear them, though.


-Max

 

Max, would you mind posting a link in here with your build? Thank you!

Chris

Edit: http://www.avsforum.com/t/1440924/seos-15-dna-360-ae-td15m-center-channel

Got it.

 

Thanks for providing your thoughts Max. I haven't heard one bad review on any SEOS kit. You definitely need to build the L&R speakers. You built a nice cabinet so not sure why you wouldn't build the same so your LCR all match. I'll be referring to your build since you had some good tips.

 

I'd think any SEOS12 speaker would be a good match at center It would set most of the speaker's character.

 

Glad you found the link, Chris.


Donivan, thanks for the kind words about my cabinet. I want to build towers for the L&R for aesthetic reasons, so I don't want to do the same build. I might build the L&R ported, since they are going to be big anyway and that would make them more versatile. It turns out I built my center cabinet just a tiny bit too tall, so it doesn't fit in the fireplace like I originally planned. That got me thinking, and I'll probably build a new cabinet for the center that will be even taller and will intentionally be placed in front of the fireplace. I generally just like building stuff, and that's part of why I like this hobby.


I've got parts for three SEOS-15/TD15m speakers, so that's what I'll be using for LCR. I do imagine that a SEOS-12 center could work quite nicely as well. There are definite differences in the sound of my Econowaves and my SEOS center, but they are similar enough to not offend when used together. I can only imagine that all SEOS designs with the same compression driver would be pretty seamless.


I got my crossover parts from PE today, and I just loaded up this thread on a laptop in my garage to build the passive crossover for my center.


-Max

 

I haven't listened to it yet, but I've got a crossover built to try out tomorrow:



More details about the crossover build here:
http://www.avsforum.com/t/1440924/seos-15-dna-360-ae-td15m-center-channel/30#post_23030508


-Max

 

Thank you bwaslo for sharing this.
If I may ask what the implication would be In using a 4 ohm TD15-M with this design.
JL

 

You would have to scale the woofer part of the crossover (double capacitor values and halve the resistor and inductor values). But you would also need to increase the tweeter sensitivity by 6dB. You might be able to get there by adjusting the 12 oh resistor to around 4 ohms but might need to mess with the values of the 2.7uf cap and the resistor across it. Generally not an easy thing to do, using a different woofer impedance probably should get a new crossover design altogether.

 

I was hoping for a simple L-Pad fix, and the resulting impedance would just show 4 ohms. I'm In over my head.. But with that direction and some tutorials In PCD I hope to make sense of It all. Thanks again
JL

 

Bill, while I understand you already selected what you consider the optimal crossover point for this pairing, do you think the crossover could be brought down to 900Hz without significantly compromising the directivity match-up?

 

Would this crossover work if I used the Celestion 15" buyout woofer instead of the AE TD-15M? I realized the AE woofer is a much better woofer, but I am trying to keep my costs down and already bought the Celestion 15" woofers from PE.

Thanks in advance for your reply.

Mike

 

Brinkman,
You could probably come up with a crossover that works at 900 Hz, but you'd have to do some modeling. You can't usually just change a part or two.

210flyer,
There's the one with the SEOS12 at http://www.diysoundgroup.com/forum/index.php?topic=221.0, but to do it with a SEOS15 would also probably require some modelling to do a crossover. I think the TD15M cone is deeper than the buyout is.

 

Thanks, Bill !!

I guess I'll stick to my original plan and build the "Cheap Thrill" without altering the design. I don't currently have the knowledge to tackle a new crossover design and the 15" plastic waveguides aren't even available yet.

 

So I've installed PCD (2003) onto my PC (I'm new to the PC world). My version of excel is the 2003 iteration.

I finally figured out how to make PCD "see" the .zma files for this project (as copied here).

[/size][SIZE=small]At first, they stayed as notepad type files and excel would not load them in the PCD program (despite their .zma extension), but the PCD program [/SIZE][SIZE=small]would [/SIZE][SIZE=small]recognize the .zma files in the PCD tutorial folder as excel type files. So I cloned those .zma/excel files, pasted them and renamed them. Then I copied the data from the .zma/notepad files and pasted them over the data in the cloned files. Now PCD recognizes them and allows me to import them into PCD, but my FR is way off.[/SIZE][size=78%]



Any help here?

 

Sorry to ask a silly question Bill, but I am confused. The title says TD15M/SEOS15 DNA360, but the schematic says the 250 CD on it. Which is this project optimized for?? I have Matt(mtg90) working out my mega seos lcr build now and we have been discussing the surrounds. I have a house full of TD15M woofers and am going to build with them so, we were originally going back and forth on the seos15 and seos12 WG. Initially the 12 was the winner because there was a xover design out there, but Matt isn't 100% happy with it. If the xover you have is optimized here for the combo with the seos15, it could be a real winner for me and save some time for Matt. Thanks in advance!

 

The heading on the schematic says DE250 CD on it but the text in the diagram below where the tweeter connections are shown says "DE250 or DNA360 on SEOS 15 waveguide".


I am intending to use this crossover for a TD15M and DNA360 combo when the plastic SEOS 15's finally arrive.


Tim

 

The DE250 and DNA360's FR and impedance are similar enough that a crossover for either should be interchangeable.

 

Thanks guys, I thought that was the case, but wanted to be sure. I am using the TD15M DNA360 combo in my surrounds....going back and forth on my choice of waveguide between the seos12 and seos15. I'm not sure if the change to the 15 on surrounds is necessary, and I'm sure the 12 will work fine (had Sentinels and it was good in those). I just haven't had the chance to hear a 15 to know if it's that much better. I have the woofers and plan to order either waveguide with the 360s this week and start building. Any thoughts to those with experience on the 15 to the 12 seos?? Matt thinks the 12 will be fine and I trust his word on this. He has a xover design for the seos12 360 combo with the TD15M too. Thanks guys