I do find it interesting though that Danley's designs really disagree with a pure 'Geddes' take on horns / waveguides. Tons of diffraction and reflections in the horn, barely if any throat transition and no mouth termination (unless you count the secondary flare, but that has a different raison d'être).
That's another aspect about Bill's waveguide that appealed to me, it kind of takes the "minimal diffraction" camp's concerns into account. Less so in the 'stub' version, but I suppose that's unavoidable if one wants to be able to work with sheets of plywood.
That's another aspect about Bill's waveguide that appealed to me, it kind of takes the "minimal diffraction" camp's concerns into account. Less so in the 'stub' version, but I suppose that's unavoidable if one wants to be able to work with sheets of plywood.
If you look at the polar response of a synergy horn, it shows that there is not much diffraction / reflection going on, coming from the woofer ports. At least I find the benefits of a synergy horn far greater, than the possible drawbacks.
Have you ever heard a well implemented synergy horn? I can only attest to the many positive reviews others have reported. It sounds really good to my ears. It does pin point accuracy like a 2 way monitor, transparency like an electrostat and to that it adds the horns low distortion, dynamics and efficiency. It just blows everything out of the ball park in my view/ears.
I have had nice 2 ways with subs, linearrays, wisdom audio planars, Tannoys with 2 X 15", big 4 way tractrix horns and they don't come close by a mile to the synergy. I really believe they are way ahead design wise, which also translate to better sound.
Look up a pair to listen to, or even better get a pair 😛
Have you ever heard a well implemented synergy horn? I can only attest to the many positive reviews others have reported. It sounds really good to my ears. It does pin point accuracy like a 2 way monitor, transparency like an electrostat and to that it adds the horns low distortion, dynamics and efficiency. It just blows everything out of the ball park in my view/ears.
I have had nice 2 ways with subs, linearrays, wisdom audio planars, Tannoys with 2 X 15", big 4 way tractrix horns and they don't come close by a mile to the synergy. I really believe they are way ahead design wise, which also translate to better sound.
Look up a pair to listen to, or even better get a pair 😛
I'm with you, otherwise I wouldn't spend all this effort on the implementation of the synergy concept!
But the fact remains that Danley's synergies don't pay attention to these details like throat matching or large roundovers. This in my mind means that either everything the 'geddes camp' has been on about is largely irrelevant or that it would actually be useful to add these details to a synergy design. The latter is kind of my point.
But the fact remains that Danley's synergies don't pay attention to these details like throat matching or large roundovers. This in my mind means that either everything the 'geddes camp' has been on about is largely irrelevant or that it would actually be useful to add these details to a synergy design. The latter is kind of my point.
Remember that Danley's are made for PA and not designed for the more, soundwise, critical home market. Most of his horns have a smaller radiation pattern, 50x50 or 60x60. For home use I believe 90x60 works better. My Behemoth looks like Danley SH 90x60, mine are a little bit bigger. Different driver topology though, but I don't need 150 dB in my listening room 🙂 So the best thing is to really build your own using Bill Waslo's design spread sheed or go the 3d print route. A K-402, SEOS 24-30 horn can also work for a large synergy, but then you would have to make holes in an expensive horn, so no room for errors.
I believe that Bill's 3-d designs have the proper throat-to-mouth transition, to work perfectly.
I did the round over at the Behemoth mouth with 4" cardboard tubes, cut in halves.
I believe that Bill's 3-d designs have the proper throat-to-mouth transition, to work perfectly.
I did the round over at the Behemoth mouth with 4" cardboard tubes, cut in halves.
The synergy and most of Danley's speakers up until recently were designed for sound reinforcement, where pattern control and SPL are the two things that really matter.
In the SM60 there is a moulded horn where more attention has been paid to smoothing things out. This is the basis of the Hyperion home speaker.
I have BEM simulated a straight conical of the same rough size and angles as the SH50. Adding a secondary flare really cleans up the polar response so there is a better termination than a straight horn.
I have simulated the taps in a waveguide made with Ath and when modelled as hard reflective surfaces it is a total mess. The problem is that this is not what is really happening and there is damping going on from the ports so there is nowhere near as much diffraction and reflection as you might imagine from looking at it.
The construction difficulty of making rollback terminations is doable but difficult for most and the stub like bill designed takes care of a lot of the stuff at the throat and the OS throat will help CD's with flatter exit wavefronts. Put the two together with flat sides for the rest and I think you would have tackled most concerns.
The round over part (rollback), was not that difficult. Using half tubes and then filled the back with expanding foam.
Without rollback
with
Without rollback
with
I totally agree with both of you and I'm not trying to criticise Tom Danley (or Earl Geddes for that matter) in any way. I'm just saying that for the use case of hifi or studio situation it's probably beneficial to add a smooth throat transition and large mouth roundovers to a synergy. How much you will acutally gain from that I don't know. As schlager does, I also have 4"-tubes here and once I get around to properly measure the 3d printed MEH's pictured above I'll do so with and without.
My comment about the secondary flare was more about the sound quality (the whole HOM debate) than the pattern, I'm aware of the benefits of a secondary flare in that regard. And you're right of course that Danley's M-series is an improvement when it comes to throat transition. But looking at the Hyperion he doesn't seem to feel that a smooth mouth termination is all that important. Unless that concentric additinal baffle (which looks like a cosmetic blind to cover mounting screws) has acoustic benefits I fail to understand.
My comment about the secondary flare was more about the sound quality (the whole HOM debate) than the pattern, I'm aware of the benefits of a secondary flare in that regard. And you're right of course that Danley's M-series is an improvement when it comes to throat transition. But looking at the Hyperion he doesn't seem to feel that a smooth mouth termination is all that important. Unless that concentric additinal baffle (which looks like a cosmetic blind to cover mounting screws) has acoustic benefits I fail to understand.
Funny you mention that. Just about 10 minutes ago the courier delivered a SEOS-30 which I plan to turn into a MEH prototype. Most of the SEOS waveguides are of the very shallow rapidly opening type. But the 18 and 30 have quite a different geometry and they're mostly conical with a smooth throat transition and a largeish roundover at the mouth. And they're 90x60, which I also like for domestic use. Plus the Autotech horns are incredibly sturdy and well built, so in both respects perfect for a MEH. But it is a little frightening to just drill holes into this beauty, the speaker graveyard is big enough already! 🙂
OMG you are playing with fire (or your money 😱) Is it for a 2" driver and what about midrange/bass drivers? Nevertheless best of luck 🙂
I don't know if the comment about the have you listened to a well made synergy was meant for me.
The answer is no I have not.
As for reviews of how they sound. It depends what you are using as comparisons I would say. If you attend regularly concerts that are unamplified and you know the sounds of these instruments and they are faithfully reproduced then yes that is a good reference.
If you are listening to normal monaural microphone recordings that are processed and panned to generate a two channel effect that is not so much a faithful rendering of the sound as it is a contrivance of the recording engineer. Some are stunningly good. Many are not.
I play French Horn for 6 years in school and attend live concerts fairly regularly, not for the pas year and a half of course. But I remember what instruments sound like, as well as real hall ambience. I love the dynamics that a truly high efficiency speaker can allow if it is in the source material. Hence my interest in this idea.
You guys are teaching me a lot. And I am grateful to read and learn.
So many have contributed. And most everyone has a good point to take and think over. Thank you.
The answer is no I have not.
As for reviews of how they sound. It depends what you are using as comparisons I would say. If you attend regularly concerts that are unamplified and you know the sounds of these instruments and they are faithfully reproduced then yes that is a good reference.
If you are listening to normal monaural microphone recordings that are processed and panned to generate a two channel effect that is not so much a faithful rendering of the sound as it is a contrivance of the recording engineer. Some are stunningly good. Many are not.
I play French Horn for 6 years in school and attend live concerts fairly regularly, not for the pas year and a half of course. But I remember what instruments sound like, as well as real hall ambience. I love the dynamics that a truly high efficiency speaker can allow if it is in the source material. Hence my interest in this idea.
You guys are teaching me a lot. And I am grateful to read and learn.
So many have contributed. And most everyone has a good point to take and think over. Thank you.
Haha, I suppose I am. But during the last well paid job I thought to myself "wouldn't it be great to do the next one monitoring through some nice synergies?". So I set aside a bit of money that I'm ready to have wasted if I fail at this. They're actually surprisingly cheap (which is of course relative) and the sturdiness and all over build quality would be impossible for me to achieve without spending a LOT more on a skilled carpenter. I live and work in the middle of Berlin without a garage or yard or anything like this. Maybe it's different if one lives in a rural or suburban area with a workshop etc. It's almost impossible for me to do any woodwork that goes beyond glueing pre-cut plywood or MDF (and the "home depots" around here only cut straight angles as well), so I've been eyeing this kind of ready-made solution for a while.
Anyway, yes it's 2-inch so requires a different approach in the first place. Right now the plan is to use a BMS 4590 plus a pair of 12-inch woofers. I'm leaning towards Faital 12PR320's. They're relatively affordable and versatile, thus easy to use for some other project if it shouldn't work out. But I'll start a new thread for that once it gets going.
For 2" driver and 2x12" you can get some good info from Chris in these threads. He uses 2" driver and 2x15" in a K-402 horn.
Full-Range Synergy Kit Questions
A K-402-Based Full-Range Multiple-Entry Horn - Technical/Modifications - The Klipsch Audio Community
For a crossover at around 400-500 hz, you should put the woofer holes around 20 cm from the start of the horn (throat). For a fullrange down to 40 hz you could make a couple of ports. Hornresp can simulate this.
Full-Range Synergy Kit Questions
A K-402-Based Full-Range Multiple-Entry Horn - Technical/Modifications - The Klipsch Audio Community
For a crossover at around 400-500 hz, you should put the woofer holes around 20 cm from the start of the horn (throat). For a fullrange down to 40 hz you could make a couple of ports. Hornresp can simulate this.
Hi, great discussion you guys have going.
Vathek, I've wrestled with the contrast between Geddes' and Danley's apparent attention focus too.
And have basically come to the conclusion that Geddes' overriding concern is with sound 1kHz and up; whereas Danley's is with integrating the entire audio spectrum.
My 2c...hope i haven't mischaracterized either of the gentlemen's focus.
I've added secondary flares to several primary conical horns, tried roundovers (none as big as the 4" tubes however), and am thinking about trying some felt around the mouth ala Charlie Hughes.
One set of secondary flares was curved glassed foamboard attempting to mimic the K402 flares. here's a pict of a few of the builds
On anything i've built, whatever the H/V pattern, adding secondary flares has helped polars some, particularly in the 1-2 khz range.
Oddly, I can't say I've really noticed any change in higher frequency sound.
I have heard a downward shift in tonality from what i figure is lower pattern control from the larger mouth, but that's about it really.
I've also played with throat matching as best as possible, and flat leaving the mismatch alone. Can't hear a difference.
I think I'd just say I'm a bit deaf maybe, but I can't measure any difference I'd judge significant, either.
Like all of us, I want the best sound possible, so i keep working on throat matching and mouth termination details. But i'm really beginning to wonder if it's worth the attention/effort.
schlager, I strongly agree with your take on Synergies in #222...i simply haven't heard anything i like better than my DIYs, and have been blessed with enjoying/owning a number of other speaker types for comparison.
I hear you mark100, throat matching is nice to have, not need to have. Though I would say that as long as the driver exit angle is smaller than the horn entry, all is fine. My view on roundover at the mouth depends on horn size. A small horn should have a roundover as the mouth will be closer to the throat and the energy at the mouth would be higher, than it would be on a larger horn. Also in a small horn the cutoff frequency will enter +800 hz where our hearing is much more sensitive to smearing and time domain issues, caused by the reflections back into the horn.
Thanks! I'm aware of Chris' big MEH, even posted there about possibly using the SEOS-30 and he was decidedly disinterested in using anything smaller than the big Klipsch. But it seems he has changed his mind, there's even a thread about the SEOS-30 now. Anyway, certainly some good info and experience there.
With the relatively wide geometry of the SEOS, at 20cm down the horn, the circumference of the plane the ports 'make' is significantly longer than a wavelength at 400-500Hz and that's the one rule I don't want to break. For me the point source behaviour is paramount, so the quarter-wavelength distance of the ports trumps everything. But as you say, I do need to consult Hornresp.
Thanks for your input, mark100, that's really helpful. My experience for example with a pretty badly matching 1,4 to 1,5 inch adapter (I mean really bad) has been similar, I couldn't hear a difference (same driver on the same horn, only one with a native 1,5" throat, both next to each other). In comparison the Gedlee Abbey (kit) I used to own took great care that there not be the smallest discontinuity around the throat.
And schlager, your thoughts on the importance of roundovers on small vs large horns at least intuitively make a lot of sense.
And schlager, your thoughts on the importance of roundovers on small vs large horns at least intuitively make a lot of sense.
So, having just bought one of these
https://qidi3d.com/products/qidi-tech-x-cf-pro-industrial-grade-3d-printer?variant=39924199194760
I'm collecting ideas for a project. I already have a baic 2 way i'm running with as an early project, but I have always been interested in the synergy horns. I dont have a big space to fill, Do you think they could be modified for near field use?
https://qidi3d.com/products/qidi-tech-x-cf-pro-industrial-grade-3d-printer?variant=39924199194760
I'm collecting ideas for a project. I already have a baic 2 way i'm running with as an early project, but I have always been interested in the synergy horns. I dont have a big space to fill, Do you think they could be modified for near field use?
MEH (Multiple Entry Horns) don't need modification to sound good for near field use.
I hoped as much. The point source nature would seem ideal, but most (all) of the builds i'e seen have been biggish. I dont have the ability to sofit-mount, So masically as long as reasonable spacing from desk and rear wall is obeyed i'm all good? I'll be running DSP too.
Did you see my compact MEH? https://www.diyaudio.com/community/...eh-unity-synergy-speaker.382400/#post-6923745
XRK and Bushmeister made theirs even smaller
XRK and Bushmeister made theirs even smaller