I used to have a stereo-lab 400hz tractrix horn coupled to an Altec 299 1,4" compression driver. This combo beamed too much for my taste.
Will a combo with a Radian 2" driver with the horn below beam as much? And how high will it reach 16-17 khz with some eq?
The horn is a Le-Cleach 48 cm wide, 24 cm deep.
Will a combo with a Radian 2" driver with the horn below beam as much? And how high will it reach 16-17 khz with some eq?
The horn is a Le-Cleach 48 cm wide, 24 cm deep.
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This begs the question, will it beam as much as the 1,4" 400hz Stereo-Lab tractrix horn? Which is deeper and has a more narrow expansion rate.
I like the Le Cléac’h, I had never seen it before
(Azurahorn -Le Cleac'h Acoustic Horn Loudspeakers)
Basically, all compression drivers have a high end rolloff in their power response, due to a combination of moving mass and also phasing of the sound across the diaphragm. A truly constant directivity horn will therefore roll off at the high end. But it's not the horn's fault, it is a natural feature of all drivers. Some horns try to get flat response on axis, and to do so they must progressively beam the highs to keep up the on-axis SPL.
I found this analysis:
LeCleac'h horn vs Conical Horn
It's all simulation, but seems likely. Bottom line would be the Le Cléac’h should beam a lot less than a typical exponential. Unfortunately, I'm not recalling about Tractrix and beaming. Are you really objecting to beaming, or to some kind of resonant peak?
(Azurahorn -Le Cleac'h Acoustic Horn Loudspeakers)
Basically, all compression drivers have a high end rolloff in their power response, due to a combination of moving mass and also phasing of the sound across the diaphragm. A truly constant directivity horn will therefore roll off at the high end. But it's not the horn's fault, it is a natural feature of all drivers. Some horns try to get flat response on axis, and to do so they must progressively beam the highs to keep up the on-axis SPL.
I found this analysis:
LeCleac'h horn vs Conical Horn
It's all simulation, but seems likely. Bottom line would be the Le Cléac’h should beam a lot less than a typical exponential. Unfortunately, I'm not recalling about Tractrix and beaming. Are you really objecting to beaming, or to some kind of resonant peak?
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60cm JMLC, 2", starts to beam above 20deg:
http://www.diyaudio.com/forums/multi-way/155663-min-phase-horn-faital-drivers-german-diy-show-gelsenkirchen-6.html#post2076012
http://www.diyaudio.com/forums/multi-way/155663-min-phase-horn-faital-drivers-german-diy-show-gelsenkirchen-6.html#post2076012
Yes, Tractrix and Le Cleach horns beam. That is their nature and they have very good sound but if you are concerned with beaming then don't sit closer than - lets say 12 feet from the speakers. All else being equal, I do not think tractrix has any problems provided it is not expected to do super wide range duty.
Cheers
Cheers
Why not make a cone shaped "phase plug" inside the horn to improve dispersion? Held in place by a geddes style foam plug?Better dispersion, and redused HOM's at the same time.
Bump, anyone tried this?
Why not make a conical shaped "phase plug" inside the horn to improve dispersion? Held in place by a geddes style foam plug?
Bump again
More crossover points, and less of a point source dispersion, which is things I dont like in my loudspeakers
Wouldnt it work to just use a plug pictured above to reduse beaming?
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Joined 2003
Because I like the sound of these horns, and I've have yet to find a 400hz cf waveguide. I frequenly see fullrange drivers with large phase plugs to improve dispersion, why not do the same with tractrix/Le Cleach horns? I guess you would have to eq the top end though, to get flat on axis?
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Member
Joined 2003
Yes, if you move toward a constant directivity WG, you will need more top end EQ for flat on-axis response...but think about where that additional energy goes. Assuming a phase plug changes polar response, and therefore modifies in-room direct/reflected energy, the result will sound different than the horns you say you like. Better than the horns you like? Worse?
It seems doubtful you can find a phase plug design that won't muck up a tractrix or LeCleach flare. So, IMO, the best solution for you is to pick a proven horn/WG design and buy or build it. If you want to try a CD WG, DDS makes a 24" WG that may approach 400Hz.
It seems doubtful you can find a phase plug design that won't muck up a tractrix or LeCleach flare. So, IMO, the best solution for you is to pick a proven horn/WG design and buy or build it. If you want to try a CD WG, DDS makes a 24" WG that may approach 400Hz.
Don't stick a plug in the middle of the horn to get wider directivity. That will just give you more reflections. Instead build a horn or waveguide that gives you the pattern that you want.
Related to your earlier question about LeCleac'h vs tractrix, in some cases at least the LeCleac'h will have wider (lower) directivity at some frequencies. See below:
LeCleac'h 275Hz:
Tractrix 275Hz:
Looking at the -6dB curves, the LC is about +/- 40 degrees at 500hz, about +/-30 at 1kHz, and a bit over +/-20 at 3kHz (a decade about the flair frequency). The tractrix is about +/- 45 degrees at 500hz, +/- 25 at 1kHz, and a bit over +/20 at 3kHz. So the LeCleac'h looks to be narrower at low frequencies and its pattern narrows smoothly as frequency increases while the tractrix goes down to a narrower pattern and then stays more constant as frequency increases. I imagine you could build a LeCleac'h with a faster flair and it would have a wider pattern.
Related to your earlier question about LeCleac'h vs tractrix, in some cases at least the LeCleac'h will have wider (lower) directivity at some frequencies. See below:
LeCleac'h 275Hz:
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Tractrix 275Hz:
An externally hosted image should be here but it was not working when we last tested it.
Looking at the -6dB curves, the LC is about +/- 40 degrees at 500hz, about +/-30 at 1kHz, and a bit over +/-20 at 3kHz (a decade about the flair frequency). The tractrix is about +/- 45 degrees at 500hz, +/- 25 at 1kHz, and a bit over +/20 at 3kHz. So the LeCleac'h looks to be narrower at low frequencies and its pattern narrows smoothly as frequency increases while the tractrix goes down to a narrower pattern and then stays more constant as frequency increases. I imagine you could build a LeCleac'h with a faster flair and it would have a wider pattern.
Could you elaborate a bit please?
I dont see why a small shallow plug could be so bad? But I guess the use of them in fullrange apps is a bit different then in horns.
I am not concerned with beaming as I only sit in one position when I listen to music. When I am not "listening" and have the system on, I am doing things around the house and the music is just background. Maybe I am missing something, but if your system is not in a night club or trying to have equal coverage across a wide audiance, then beaming should not be an issue.
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