Møjn Thomas
Very interesting. I look forward to meet a fellow synergy-enthuiast. Most of my HiFi friends simply do not understand what I am trying to achieve with a synergy, and are very suspicious about horns and the tap-holes.
I will send you a PM
Steffen
Very interesting. I look forward to meet a fellow synergy-enthuiast. Most of my HiFi friends simply do not understand what I am trying to achieve with a synergy, and are very suspicious about horns and the tap-holes.
I will send you a PM
Steffen
Any progress to report Steffen ?
Also a question for you as the trigonometry is hard to think about; on a straight sided conical horn like this, the throat will be rectangular in shape and the ratio of the width : height of that rectangle will presumably be a function of the angles of the sides and top/ bottom (80:60 in your case). Does it work out that the width : height ratio of the throat matches the (in your case) 80:60, or is it more complicated than that?
Also a question for you as the trigonometry is hard to think about; on a straight sided conical horn like this, the throat will be rectangular in shape and the ratio of the width : height of that rectangle will presumably be a function of the angles of the sides and top/ bottom (80:60 in your case). Does it work out that the width : height ratio of the throat matches the (in your case) 80:60, or is it more complicated than that?
Hi Studley
Sorry, no progress here🙄. I hate it, but sometimes life goes strange ways. I am forced to do something about two roofs to get rid of some bad materials before it is illegal to do it by my self after new-year! Occupies all my energy at the moment. Well, but then it is done and I can hopefully concentrate on the synergy´s again!
I am good at woodworking but still need to learn to use REW to be sure to place the taps at the right place.
And now to your question: I hope I understand you correct!? I used horncalc by Bwaslo, but detected minor errors and choose to recalculate the initial horn, approximating the dimensions given by horncalc for the desired low directivity control.
The conical horn is not a pyramid with all panels creating a vertex. If it were that, then the throat would be rectangular and not square!
So you have to start with calculating from a square throat an use the angles you prefer. Calculate in vertical and horizontal direction and find the penal-lengths (and dimensions) given that in both direction you need to use the same depth of the horn. Then it should be basic trigonometry. It needs a bit of 3D-thinking. I used some cardboard to check my first model/idea and was 2543% wrong, but then I got it!
I choose to simply take over the angles as proposed by horncalc, and that proofed to be OK.
I hope this helps or just ask again, then I will dig out my calculations from my pile of papers.
regards
Steffen
By the way. What are you planning to build?
Sorry, no progress here🙄. I hate it, but sometimes life goes strange ways. I am forced to do something about two roofs to get rid of some bad materials before it is illegal to do it by my self after new-year! Occupies all my energy at the moment. Well, but then it is done and I can hopefully concentrate on the synergy´s again!
I am good at woodworking but still need to learn to use REW to be sure to place the taps at the right place.
And now to your question: I hope I understand you correct!? I used horncalc by Bwaslo, but detected minor errors and choose to recalculate the initial horn, approximating the dimensions given by horncalc for the desired low directivity control.
The conical horn is not a pyramid with all panels creating a vertex. If it were that, then the throat would be rectangular and not square!
So you have to start with calculating from a square throat an use the angles you prefer. Calculate in vertical and horizontal direction and find the penal-lengths (and dimensions) given that in both direction you need to use the same depth of the horn. Then it should be basic trigonometry. It needs a bit of 3D-thinking. I used some cardboard to check my first model/idea and was 2543% wrong, but then I got it!
I choose to simply take over the angles as proposed by horncalc, and that proofed to be OK.
I hope this helps or just ask again, then I will dig out my calculations from my pile of papers.
regards
Steffen
By the way. What are you planning to build?
I faced the same issues back in the day when I did my Synergy. BWaslos XLS is a good starting point but I went from there to a graphical construction in a 3D CAD program, Sketchup. I drew a rectangular solid of depth equal to horn depth and desired mouth dimensions. Added a plane for the junction between conical and termination flares. Drew the 1" square on the back and started connecting vertices. It doesn't get confusing/challenging until you start giving thickness to the flares and have to draw intersections. Overall its much easier than doing all that trig and its self-documenting. At the end of the day you can spit out drawings for each flare...
Steffen, yes life stuff can be very annoying! We remodelled our house and it took 3 years, still stuff to do in fact 😩.
I did indeed assume the panels of the horn would come to a single point or vertex if extended that far, so what you tell me is vital information ! It does however prompt a further question. Does the trigonometry require you to have a square throat in order to create a straight sided conical horn ?
I ask about this because I already own some Viawave ribbon tweeters and I’ve been thinking about the feasibility of using them in a MEH and in particular the design of the throat adaptor. It seems to me that a rectangle to square throat adaptor might work a little better than a round to square adaptor . . .
I am currently making some woofer U frames for an ES290 horn system, but sooner or later I will make some MEHs, hence the thought experiment re the Viawave ribbons. Based on Mark‘s experience I will, like you, make a 3 way and use 4 mid range drivers. Again prompted by the fact that I already own them, I’ve wondered whether some 2.5” BMRs would work as the mid range drivers. They would also go high enough to meet the ribbons. (Four of them would get the sensitivity up to about 93dB. Perhaps I could even fit six. )
I did indeed assume the panels of the horn would come to a single point or vertex if extended that far, so what you tell me is vital information ! It does however prompt a further question. Does the trigonometry require you to have a square throat in order to create a straight sided conical horn ?
I ask about this because I already own some Viawave ribbon tweeters and I’ve been thinking about the feasibility of using them in a MEH and in particular the design of the throat adaptor. It seems to me that a rectangle to square throat adaptor might work a little better than a round to square adaptor . . .
I am currently making some woofer U frames for an ES290 horn system, but sooner or later I will make some MEHs, hence the thought experiment re the Viawave ribbons. Based on Mark‘s experience I will, like you, make a 3 way and use 4 mid range drivers. Again prompted by the fact that I already own them, I’ve wondered whether some 2.5” BMRs would work as the mid range drivers. They would also go high enough to meet the ribbons. (Four of them would get the sensitivity up to about 93dB. Perhaps I could even fit six. )
Hi Studley
You can make a straight-sided quasi-conical horn/MEH and simply start with a rectangular throat that fits to your Viawave ribbon tweeter. I do not think there is a point in making an adapter. Did that answer your question?
I say a "quasi-conical" because a "real" conical horn is like a pyramid, but I do not think it will be too bad to deviate a bit with a rectangular throat.
Diyaudio-member @xrk971 has made a MEH with an AMT driver in that way.
I will try to see, if I can find my paper with calculations tomorrow.
Steffen
You can make a straight-sided quasi-conical horn/MEH and simply start with a rectangular throat that fits to your Viawave ribbon tweeter. I do not think there is a point in making an adapter. Did that answer your question?
I say a "quasi-conical" because a "real" conical horn is like a pyramid, but I do not think it will be too bad to deviate a bit with a rectangular throat.
Diyaudio-member @xrk971 has made a MEH with an AMT driver in that way.
I will try to see, if I can find my paper with calculations tomorrow.
Steffen
Steffen, you read my mind 😀. I was indeed wondering whether I could go directly out from a throat that exactly matched the Viawave ribbon aperture. That is good news indeed. I will search out XRK’s posts on his AMT MEH. Thanks !