Actually what I did is to model a horn that fits on a jbl 244x. Hornresp doesnt calculate exit angle to my knowledge.
S1 can be measured from a driver, the exit is 49 mm. Then I just added values for S2 and length to get F12 182 Hz for exponential horn. I don´t remember where I got the 182 Hz from.
S1 can be measured from a driver, the exit is 49 mm. Then I just added values for S2 and length to get F12 182 Hz for exponential horn. I don´t remember where I got the 182 Hz from.
Thanks Marten! 4.67 it is! I already have pair of 2446s, but thanks for the tip on 2447. I will check it out.
Hi Michael, I'm having a casual audio meet this Saturday in Cary if you want to come up.
Free CAD programs usually can't import raw XY coordinates, but I found this little java app that converts X,Y into DXF polyline which will import into any CAD.
Converting Coordinates to DXF or SVG 2D Polylines
Hi Michael, I'm having a casual audio meet this Saturday in Cary if you want to come up.
Free CAD programs usually can't import raw XY coordinates, but I found this little java app that converts X,Y into DXF polyline which will import into any CAD.
Converting Coordinates to DXF or SVG 2D Polylines
The spreadsheet is incomplete when you download it. You need to highlight row 41 ( I will confirm it is 41 when near my pc) and drag it down over 2000 (2045 maybe) rows to allow excel to work out the formula. I will confirm the exact numbers later for you. It takes a few minutes to do so, so save it as a master copy.
all,
If this post is misplaced please let me know. I've been working through some of the spreadsheets here - have a post asking for some math validation...
Post located here - Can anyone assist? Basically I am looking to build a waveguide for Tweeter to handle the physical offset to a known woofer - which mean the depth is basically constant.
See post here: http://www.diyaudio.com/forums/mult...on-radius-validation-any-takers-new-post.html
M
If this post is misplaced please let me know. I've been working through some of the spreadsheets here - have a post asking for some math validation...
Post located here - Can anyone assist? Basically I am looking to build a waveguide for Tweeter to handle the physical offset to a known woofer - which mean the depth is basically constant.
See post here: http://www.diyaudio.com/forums/mult...on-radius-validation-any-takers-new-post.html
M
Are there any serious classical music listeners out there using Le Cleac'h symmetric horn profile with compression drivers? I recently heard a 300Hz pseudo tractrix horn with TAD2001. It was nice on jazz and other "relative tonality" music, but it fell apart on symphonic music where accurate tone is critical. Treble was rolled off too. I have used SEOS12 with a good Radian CD and was impressed with the treble power, directivity and low distortion at high SPL, but I was disappointed with the slight tonal coloration in classical playback when compared to good quality direct radiating tweeters. I am worried that a lot of labor to build a 200Hz horn will be for naught on the first play of Shostakovich 5! I know they can play loud, but is the frequency response of this horn flat enough to not color the tone as most horns do?
I'll be using 2446 with titanium at first, will upgrade to Be diaphragms if the horn warrants it.
Thanks
Rich
I'll be using 2446 with titanium at first, will upgrade to Be diaphragms if the horn warrants it.
Thanks
Rich
I have not heard any commerial horn that totally convinces me, but some do show some very encouraging sound. Some technical aspects look promising as well. I have been reviewing some previous analysis and tests I have. Compression drivers really are complicated, and it seems that they should be designed with specific horn integrated. I am not convinced that you could design a compression driver alone and hope for optimum results because every part needs to be integrally considered. Separating driver and horn should be done only when manufacutring cost control can benefit, but the whole design needs to be designed andmtested first. Personally I am going with the wave guide concept with no compression, and gradually move to a compression driver. Of course crossover design is also important, but that is the more flexible part of the design. The LeCleach type expansion has shown very interesting qualities. I think the final wave guide design will exhibit some of the qualities. Since the shape can be similar with other expansion equations within manufacturing tolerance, it will be had to say what kind of curve it will be in the end.
There is music, that you can listen with horns, and you will not perceive any typical horn coloration. The coloration will remain hidden. Like brass instruments, jazz, guitar, drum, some instrumental, rock etc. But if you want to test tonality and coloration, play a good recorded human voice, and voilá. Even better : Compare midrange horns, almost all of them, playing voices, with direct radiators, and the difference becomes immediately clear. Even if you use a shallow wave guide or constant directivity horn. It doesnt matter. The horn distorts the soundwaves. One of the big responsables for this is also the phase plug of compression drivers. The less critical for horn coloration is bass, and treble. The worst, midrange. Despite of this, most hornloaded speakers use horns exactly in the frequency range, where it is the worst to use them......If you want a natural sounding speaker, do your ears a favour : run away from midrange horns, specially in combination with compression drivers.
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Hello,
Please note that the Le Cléac'h axisymetrical horn is not in anyway a tractrix horn.
The expansion law is different and such is the profile. the Le Cleac'h horn while preserving an hypex expansion insuring the most resistive load in a very wide interval of frequency to the driver.
Additionally the Tractrix cannot naturally have a rolled back profile at mouth and gives more diffraction at mouth than a Le Cleac'h horn with its naturally rolled back mouth.
Due to the increased directivity at HF my advice is to cross the axis of the horns in front of the listener's head.
Please read my message :
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-925.html#post3613618
"We have a lot of experience here in France with large Le Cléac'h round horns. We succeed in reducing the effect of the beaming inherent to that kind of horn rotating the axis of the horns to cross in front of the listeners head. Depending on the distance between the 2 loudspeakers , the crossing point of the horns axis can be from 80centimetres (30 inches) to 120 centimeters (50 inches)."
"Such horns should never be listened with parallel axis or small angle axis."
"Additionally, that kind of set up allows a nearfield listening with 3D image effect."
and Lynn Olson seems to agree :
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-925.html#post3615539
Most audiophiles listening to Le Cléac'h horns agree that this horn doesn't have any of the classical "horn sound".
Angelo is one of the very few persons that disapprove the use of horns in the medium range. Most audiophiles agree that it is particularly in that range that horns beat director radiators ... He is probably to much accustomed to the sound of director radiators to perceive the plus brought by the use of a horn. (All recording studios use horns for the medium frequency range).
Someone told you to pay much attention to the crossover. I agree and my advice is to never uses a tractrix horn or a Le Cléac'h horn with the high pass crossover frequency near the acoustical cut-off of a medium horn. Most negative experience people have with horns are due to the use of a crossover problem.
Best regards from Paris, France
Jean-Michel Le Cléac'h
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This kind of blanket statement is not very helpful. Furthermore, it discourages serious exploration of the concept.
@Richidoo,
Asking the TAD 2001 to perform in a 300 Hz tractrix horn is like asking a pygmy to compete in a hurdle race.
I think you will loose high frequency extension and beaming will be significant. The low end will also be outside the TAD comfort zone. Don't cross it much under 1000 cycles.
On the right horn, the TD 2001 will cover the entire harmonics range to 20kHz just fine. I have not heard this particular driver on a le Cleac'h horn (heard it on a TAD horn), but I am pretty convinced it will be a terrific combination.
You can read more about this combo in the driver+horn shoot out from the European Triode Festival report (2011 I guess).
Best
Kris
Hello Kris,
I have been using during many many years my TAD TD2001 on Le Cléac'h horn having an Fc = 320Hz above 800Hz with great satisfaction.
I always choose for my horns to use them above the frequency at which the group delay falls below 0.3ms .
Best regards,
Jean-Michel Le Cléac'h
Thank you for the responses, gentlemen. This is encouraging, and sparks more questions.
Angelo, I am glad you share my allergy to inaccurate mids.
Unfortunately I will not be using TAD 2001 on my horns. I think it is the best CD of all. But, yes the highs were somewhat subdued in this TAD2001 horn, which prevented using much toe in angle.
I will be using 2" JBL 2446H in 200Hz (.96m dia) Le Cleac'h horn with >360deg rolled back edge, T=.8 and matching driver exit angle 4.9deg.
I have a couple other questions, if you don't mind.
JM, Is 0.3mS max GD a constant for all size horns, or is it frequency dependent? Is there a simple ratio like F3 > 2*cutoff?
I know that the LF response cannot be boosted because distortion rises quickly below cutoff frequency. But is modest boost appropriate for treble response to avoid a separate tweeter when using a 2" CD for mids?
Lastly, is there a different spreadsheet published for designing non-round LF Le Cleac'h expansion horns? Like something for 100-600Hz? Or is tractrix good enough for that?
Thanks!
Rich
Angelo, I am glad you share my allergy to inaccurate mids.
Unfortunately I will not be using TAD 2001 on my horns. I think it is the best CD of all. But, yes the highs were somewhat subdued in this TAD2001 horn, which prevented using much toe in angle.
I will be using 2" JBL 2446H in 200Hz (.96m dia) Le Cleac'h horn with >360deg rolled back edge, T=.8 and matching driver exit angle 4.9deg.
I have a couple other questions, if you don't mind.
JM, Is 0.3mS max GD a constant for all size horns, or is it frequency dependent? Is there a simple ratio like F3 > 2*cutoff?
I know that the LF response cannot be boosted because distortion rises quickly below cutoff frequency. But is modest boost appropriate for treble response to avoid a separate tweeter when using a 2" CD for mids?
Lastly, is there a different spreadsheet published for designing non-round LF Le Cleac'h expansion horns? Like something for 100-600Hz? Or is tractrix good enough for that?
Thanks!
Rich
I use a horn in my home, from 1500 Hz to up and i had a big horn in my movie postproduction mixing studio from 750 Hz to up. With a 1" JBL driver.
Both based on a spherical curves, not far from JMLC.
The most natural sound i ever had. Not the slightest "horn coloration".
We have recorded a little Jazz band in the studio, and it was amazing how the tape sounded like the original in the same big room.
And, you know, movie post prod... not only music, but all kind of human voices and sounds...
It was the only place where, calling some comedian's name (speakers at the opposite area from the mixing desk) during voice over recordings, you got people turning its heads in the direction of the speakers.
About my studio monitors, a revue of those speakers, from a HIFI magazine:
http://www.esperado.fr/temp/critique-en.html
http://www.lamaisonduhautparleur.com/pdf/KIT-AERIA-SYSTEME.pdf
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Hello Rich,
I use for myself the 0.3ms limit for all horns having a cut-off over 250Hz.
Under a cut-off of 250Hz I am far less sensible to the group delay rise observed in horns (may because we observe also such rise in the group delay at low frequency with bass-refelx and even with closed enclosures).
I use myself, with great satisfaction, passive equalization (a series resistor with a capacitor in parallel) to be able to avoid the use of an additional tweeter.
Hornresp, the excellent software written by our friend David McBean can export Le Cléac'h profile (even multifacets).
Best regards from Paris, France
Jean-Michel Le Cléac'h
Best regards
LOL! Just because you've had bad experiences with horns, doesn't mean they are bad. Sure, there are lots of bad implementations of horns, but the good ones prove that it can be done. As Esperado says: "Not the slightest 'horn coloration'."
Horn crossovers take time, patience and skill. If you haven't heard an excellent horn system, you may not know what's possible and thus not take the time to make it right. Horns, done right, can be far less colored than other types of speakers.
Be is a waste of money for a 200 Hz horn. Go for a Radian diaphragm in the 2446, it has mylar sourround which is not as stiff as titanium. Or swap the driver for a 248x with phenolium diaphragm, or use a BMS 4591
Don´t use this horn above say 3 kHz. You will need a smaller LeCleach above it. A TAD CD maybe? Or a Radian CD.