Why Synergy horns?

In another thread I was asked, if I would provide more details about my speakers, so I thought why not?

I have played on active 4 way horn systems since 2016. First iteration was front loaded bass horn, midbass horn, tractrix midrange horn and tractrix tweeter horn. I worked nicely, with all the attributes associated with well implemented horns. Clarity, dynamics, realistic live sound etc.

However some problems will arise, with such horns. First of all, the center to center distance between the different horns is big, compared to the crossover frequencies. We need to be within 1/4 wave in distance at x-over for a seamless transition. For instance if you x-over from the midrange horn to the tweeter horn at 3 KHz the c-to-c distance would have to be 340/3000/4= 2.83 cm (1.11 inch). This is virtually impossible with "normal" horn configurations. This problem rears its ugly head, at every x-over throughout the audio frequency range. As frequency decreases, the wavelengths gets bigger, but so does the horns in the specific bandpass and then c-t-c also increases. It is a linear problem, that can't be solved with the regular approach, aka stacking horns on top of each other. This creates interference problems and lobing in the vertical response curves, that will color the reflection from floor and ceiling. Secondly a large column of vertically stacked horns, will push the sweet spot (SS) further back, for the horns to be perceived as more coherent and integrated, with one another.

But the biggest problem is that almost all horns beam with increasing frequency, it's their way of nature so to speak. What that means, is that the off-axis FR will not be similar to the on-axis FR. This translate into a poor power response, which is not considered a good thing, in terms of best sound quality.

Luckily we can circumvent all these problems with clever engineering and have our cake and eat it too, so to speak. Enter the Synergy horn.synergy.jpg
 
Last edited by a moderator:
The Sourcepoint video from Sterholm left me wanting for more. It would be interesting to understand how different speakers compare, to get a better sense of their "personality".

On a side note, while I appreciate his sense of humor, I find he is now trying a little too hard to entertain. The "sidekick" got irritating...

There is so much going on in his videos, I feel I am watching an action movie, and it's not really relaxing, IMO.

That being said, I do appreciate the content.
 
  • Like
Reactions: schlager
Hi all.
Been reading this thread with great interest. Lotˋs of theories that goes over my head but iˋve enjoyed it a lot:)
Am waiting for a big synergy horn system that will arrive in the first week of June.
Mid/high cd is JBL2451 beryllium, mid bass is 2X18Sound 12" drivers. Sub enclosure has 2441(i think it is), 18" driver in 340 litres cabinets. 80cm wide. Reading this thread makes me even more impatient :D
The "brain" for this system is a GroundSound dcn28 unit.
Will report back with impressions and pictures when it is upǹ running.
Cheers
 
Last edited:
Here are the speakers ready for shipping. I hope to have them on Friday or Saurday this week.
Total is 80cm wide.
JBL 2243, 18" sub
Horn:
2X18Sound 12ND610 each side
JBL 2451 beryllium
Crossover from sub to horn about 150HZ/LR24db
The system will be fine tuned with a microphone/soundcard later this summer/autumn by an expert on this field. Then the speakers will be integrated in my listening room. Right now i have got the digital crossover for the synergy horn but the bass i must tune in myself, with some help.

image-2.jpg
 
Fjordfunk, really nice speaker setup. Looks like there is a secondary flare in the horn. How low does the tweeter play? Is that some kind of slot loaded bass reflex?
 
  • Like
Reactions: Fjordfunk
Fjordfunk, really nice speaker setup. Looks like there is a secondary flare in the horn. How low does the tweeter play? Is that some kind of slot loaded bass reflex?
One of the horns did not have the drivers mounted when picture was taken. Subs are 18" JBL in 340 l bass reflex cabinets.
Today they arrived, finally.
What is "shocking" me is the extreme wide sweetspot. They act like point sources. Capacity is also extreme. Now i only have dialed in by ears the subˋs. Later there will be taken measurements by the designer of the system to fit the sound to the room. The lack of distortion makes me play too loud i can feel now. I feel dizzy and my ears bleeds :)
Very happy right now. The build quality is furniture grade and they are so heavy. Glad that they are in two parts, horn/subˋs
 

Attachments

  • IMG20240606180428.jpg
    IMG20240606180428.jpg
    981.8 KB · Views: 64
  • IMG20240606180840.jpg
    IMG20240606180840.jpg
    836.5 KB · Views: 59
  • IMG20240606180444.jpg
    IMG20240606180444.jpg
    622.6 KB · Views: 59
Fjordfunk, really nice speaker setup. Looks like there is a secondary flare in the horn. How low does the tweeter play? Is that some kind of slot loaded bass reflex?
Subs are now crossed at 180hz 24db/LR. Then the 18Sound 12"ˋs are taking over. The mid/high i am not quite sure of where it starts since the crossover is pretty advanced with so many settings. I guess the mid/high comes in about 600hz or so?
 
I listened to the Dali Kore recently.

To me they sounded very much what I would expect technically from such a design. That means low sound quality in several areas due to issues with combing, lobing, poor vertical directivity, and they likely also suffer from some bad diffraction.

Also, IMO it's not the right choice to design a speaker that are not aiming the drivers towards the ears.
 
Haven't heard the Kore, perhaps the Epikore 11 is a technically better design. Sure the vertical response will take a hit at some point, no way around it. Somehow I was very fond of the Epikore and I often my love for monkey coffins is very minuscule.
 
Haven't heard the Kore, perhaps the Epikore 11 is a technically better design. Sure the vertical response will take a hit at some point, no way around it. Somehow I was very fond of the Epikore and I often my love for monkey coffins is very minuscule.
Don't worry, it seems Bjorn only likes the speakers he's commercially involved with :)
 
Boys day out at Steinway Lyngdorf

1720432933848.png
1720436475823.png
1720433003438.png
1720433838009.png
We got a factory tour and lots of time to play the different systems in their showroom.

The Steinway & Sons are their high end brand and the speakers were all hooked up to various Steinway & Sons amp models with Room Perfect, an EQ system developed by Lyngdorf. The big systems were run active.

First speaker was their flagship Steinway Model D. The room was quite big about 10 x 10 x 5m and moderated damped, trying to resemble af normal living room. Model D being a dipole, in this room, threw a larger than life soundstage, as coming from a scene approx 1 m from the floor, really engaging with big orchestre classical music. The sound was smooth, detailed and balanced and you could probably sit and listen for hours on end, without fatigue, nice and pleasant. The bass had some reverberation time overhang in this large room and did not exhibit the dryness that I like and lacking the bite and punch in the bass, you can get from other speaker topologies.

1720433917526.png
1720433964736.png

Up next was the Model A (the big one with twin 12" woofers), Model O (the small floorspeaker with 6" bass/midrange) and the little Models S with boundary subwoofers.

All three systems are closed boxes and could be A-B tested, switching speakers with an app downloaded to a phone, cleverly done.

Starting with Model S, the small speakers mounted on the wall, was perhaps positioned a bit too wide, to make a solid image. The boundary subs gave a nice bottom end below approx. 300 hz, but seem to not fully integrate with the smaller speakers. I believe the system was stretched out a bit too much on the front wall, to fully come together as one. But I think this system could work very well under more ideal setup conditions.

Next up was the Model O, but here we run into the well known problem, a small 6" driver doing both bass and midrange, it simply does not work. In this price range there should not be made compromises like that.

Moving to the Model A, things started to come together. It is designed to be placed up against the front wall, to reinforce the bass and it did so with authority, plenty of slamm but still detailed and nuanced. Dynamic-wise it stood the torture test with Michelle Shocked "Quality of mercy" and like the rest of the Steinway series, it was smooth and balanced, with plenty of details. That midrange / tweeter (AMT) combo worked very well in all the speakers. Compared to the Model D, the soundstage shrinked a bit to a more normal size and was placed firmly on the floor.

Steinway & Sons / Lyngdorf is a serious player in the high end (high priced) market, with different speaker systems for almost all demands and wishes.
 
I was thinking what are the benefits of a three-way synergy horn with separate subwoofer from 100hz and below, like bigger volume results in more deep bass. Bigger driver for more effortless sound and authority. Like the beautiful ones from @Fjordfunk Powering that with Hypex class D dsp and digital x-over, controlling the low end..

Instead of 15inch mid woofers in a synergy two way design, because smalller woofers are considered better for midrange.
And then I’m planning to have a single ended triode amp for the mids and highs with passive x-over only HPF..


-Or is the difference between SQ in 12 and 15” version of the same driver neglectable?
(Efficiency is only about 1db difference..)

-What are the pros and cons of this separate sub approach?
 
Last edited:
  • Like
Reactions: Fjordfunk
One of the horns did not have the drivers mounted when picture was taken. Subs are 18" JBL in 340 l bass reflex cabinets.
Today they arrived, finally.
What is "shocking" me is the extreme wide sweetspot. They act like point sources. Capacity is also extreme. Now i only have dialed in by ears the subˋs. Later there will be taken measurements by the designer of the system to fit the sound to the room. The lack of distortion makes me play too loud i can feel now. I feel dizzy and my ears bleeds :)
Very happy right now. The build quality is furniture grade and they are so heavy. Glad that they are in two parts, horn/subˋs
Any updates on your speakers? How far into fine tuning them have you gotten? Hope you are enjoying them.
 
Any updates on your speakers? How far into fine tuning them have you gotten? Hope you are enjoying them.
Hi and thanks for your question.
The 17.this month i will get expert help to tune them in. The horns i think is good but we need to integrate the subˋs to the hornˋs. Some delay and other adjustments. Sounds very good now but i can hear the sub-bass is not 100% integrated with the rest.
Cheers
 
  • Like
Reactions: adamaley
@schlager: thank you for starting this thread and for your superb exposition on MEHs. This is for me by far the most interesting thread on WBF. As you will know there is a great deal of interest in MEHs over on the DIYA forum and quite a lot of people have built them. Many of these people are extremely experienced and have tried all manner of speakers in their “audiophile careers”. What got my attention was how many of them say the same thing ie that their MEHs are the best speakers they have ever heard. This has led me to the decision that I must make or otherwise acquire some and I am currently researching / considering all the design options. So once again, thank you !
 
To sum up the Synergy horn, it is having the imaging precision as a small 2-way monitor, the clarity and transparency like electrostatic speakers and the dynamic and lifelike sound of horns.
As alluded to in my post from a day or so ago, this comment is strikingly similar to what other MEH owners say about their speakers. This description of a speaker is exactly how I have previously imagined my ideal speaker would sound and it’s why I have to go this route.
 
  • Like
Reactions: Fjordfunk
As alluded to in my post from a day or so ago, this comment is strikingly similar to what other MEH owners say about their speakers. This description of a speaker is exactly how I have previously imagined my ideal speaker would sound and it’s why I have to go this route.
Hi iansr, sorry for the late reply and thanks for your kind words and interest in this thread. I have been busy of late, so I haven't been around here for some time, but that does not mean that this wonderful hobby has come to a grinding halt. Being a bit horny on horns and having a bunch of B&G Neo8s planar drivers collecting dust, I thought about making a dipole horn and so I did. JBL bas kopi BG Horn.jpg
I have tried to mate it with a small synergy horn and it sounds quite ok, so I'm in the process of making a second horn. At some point I might even try to make a synergy / dipole horn, time will tell. For now I'm just exploring and having tons of fun :) Cheers.
 
  • Like
Reactions: Fjordfunk

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu