DIY Synergy/Unity spreadsheet

No idea. I need to see if I can get the T/S parameters.

 

Got some preliminary TSP parameter specs -- doesn't look good for 70Hz except in a ported back arrangement -- sealed back would be something like 150Hz. Probably the thing to do would to be to use them as midrange drivers with a couple of large pro woofers outside the Synergy horn (above/below) to get them down to where they could cross to subs.

 

sadly, it won't without Danley's permission. Patented.

 

So, who are all the people reading this thread, anyway?? 2500+ views -- come on don't be shy, write something! Is anyone else gonna try making these?

I currently entertaining the thought of redoing the horns from natural oak boards, that would look pretty nice I think.

 

Walnut horns. Oooooh. I've been plotting to try some oak Synergies, but walnut would be nice. Too much $ though, given the odds I'd mess it up (no fill and paint fixes with hardwood finishes).

 

Hi db.
Well, I haven't had the Seos15/TD15m set in place since the custom Synergies ("coSynes") were done. Though that is at least partly because my back went out and I can't move the big TD15 boxes by myself now. I do think the coSynes seem more integrated; thogh not by a lot. Tom's synergy concept really does make it all sound like one driver. Not like a driver, even, more like an emission from the air in that region. The SEOS15 had a slightly different sound between the woofer and waveguide, not at all bad, but not like one driver. Some of that effect is likely psychological, it is odd with a synergy that everywhere the sound character is the same no matter how close you are to them. Of course the fact that the coSynes are 24" horns with about an octave lower directivity control doesn't hurt, either. Very easy to listen to, no mental confusion at all from split up sound sources.

I now have the coSynes playing with the subs (sealed servoed diy jobs). That did improve their sound, they go to 37 hz on their own, but not as solidly as the subs.

I'll probably sell the SEOS15/TD15 speakers if only because they are too heavy for me and also my wife likes the plain oak coSyne cabinets better than the more wild-looking rosewood veneer SEOS/TD cabinets.

 

Well, it's nothing against the SEOS or TD15, that's for sure. That combo will play louder than the Synergy I made (the drivers I used are buyouts and aren't pro style). And the SEOS's response is a little smoother and more consistent with angle at higher frequencies. I'd li ke to hear a Synergy done in a 24 inch SEOS (thogh I think the irregularities come from the side holes in Synergy; so SEOSing wouldn't help that)

 

Had a question about how humongous these were in a room. Here's a shot of the room (during some measurement, and shelves recently emptied of DVDs by my daughter). Not really too bad. The TV is a 37"

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Tom, I don't think anyone has. But if you make the files, could you please post them here?

Also, anyone who plans to make these may want to get the 2" midrange drivers while they can, I know Parts Express didn't have a huge quantity of those in stock (but I think Marlin P Jones has some also). Suprisingly, I haven't found any drivers for this particular design and size horn that seem like they'd work any better than these buyouts, both the 2" and the 6". Can't beat the price!

 

Now... Linear Phase

With some suggestions from Tom Danley himself, I put together a passive crossover circuit to approach linear phase response for the coSyne design. It works pretty well, not perfectly linear phase of course but a lot closer than nearly all speakers. Response isn't quite as smooth as with the last crossover, but I don't think the difference is enough to worry about. A plus is the crossover circuit is simpler and less lossy than the old one.
Here is a shot of the frequency and phase response, 1/6th octave smoothed:

And for those who think 1/6th octave smoothing is cheating, here is the unsmoothed (the delay plane is a bit misadusted on this shot):


The phase rise at low frequencies is because the bass design is ported, so will be approaching 180degrees phase at the port frequency (i.e., not linear phase in the bass, but with room reflections, nothing really is).

Here is the impulse response:


Not perfect. but pretty darned tight. I haven't checked to see what it does to square wave shapes yet.

And here is the crossover circuit:


Drivers are the same as before (buyout mids and woofers, Celestion CD driver.

I built it on a piece of 1/4" plywood, twisted component leads together and soldered them, then hot-glued each to the board. Very quick and easy if you are used to soldering. Here's a photo:


And here it is mounted into the cabinet (you can see all my messy wiring.. no magic cables for this guy!).


I sent the driver measurement files to Tom Danley, and he was kind enough to do a design (in the same day) for an active crossover for this speaker including EQ! The active crossover hardware I have (miniDSP) doesn't have build in sections for high order Bessel filters as Tom specified, though, so I will need to do some research on how to implement those using biquad sections in MiniDSP. Or else get a different DSP crossover system to try it with.

Hope this helps any builders out there.


-Bill