Earl,
I'm in complete agreement that the use of 3D printing, with the highest quality systems and materials is not cost efficient. The costs with the photo polymers can reach as high as $1,000 per lb. I am currently using the process for prototype development that is not audio related, it is very expensive. At the same time I don't understand why you are having to mold your baffle horn combination at a 2" thickness solid PU material? That must be an extremely slow curing hand pour system to mold that thickness.
I'm in complete agreement that the use of 3D printing, with the highest quality systems and materials is not cost efficient. The costs with the photo polymers can reach as high as $1,000 per lb. I am currently using the process for prototype development that is not audio related, it is very expensive. At the same time I don't understand why you are having to mold your baffle horn combination at a 2" thickness solid PU material? That must be an extremely slow curing hand pour system to mold that thickness.
Is panel resonance maybe not a function of level, but just of material and usage?
At the least I'd say that damping can't take the place of stiffness without changing the behaviour of the horn.
It is hand poured, but it is not slow. Cure takes only about an hour to sufficient hardness to de-mold. The 2" is made as two plates with a damping layer between. As you know there are lots of ways of making anything, but my method works well for my production volume.
I do wonder whether anyone has tried it and done comparisons.
Sent from my iPad using Tapatalk
If theoretically you had a single driver able to produce a flat response from say 200hz to 18khz or a unity/synergy type horn with multiple drivers at the throat able to produce down to the same 200hz. Could you have a single very large, say 48" waveguide to control the directivity down towards the drivers cut-off? And if so would this have any adverse affects on the high frequency?
As I understand it, the cut-off frequency of a conical horn is dictated by the horn angles rather than the mouth area. The angles and mouth area dictate the pattern control.
Ah of course.
That is why the Danley, Red Spade Audio and Dynammiks Ultima, all have a profile with two angles, I presumed this was to increase the spread directivity overall.
But for argument sake the same scenario as above. If you wanted a multi angled single horn to reach 100hz for around 200hz XO, with size being no issue (the theoretical bit). Is this possible, without causing too many compromises?...Would it sound good?
That is why the Danley, Red Spade Audio and Dynammiks Ultima, all have a profile with two angles, I presumed this was to increase the spread directivity overall.
But for argument sake the same scenario as above. If you wanted a multi angled single horn to reach 100hz for around 200hz XO, with size being no issue (the theoretical bit). Is this possible, without causing too many compromises?...Would it sound good?
It's always hard to answer questions in an abstraction of things that can't actually happen, but here goes.
Assuming that size does not matter and that I can use a flat piston source of any radius, one could make a single waveguide that would control the directivity down to the drivers resonance. To me "adverse effects" means "things that are hard to compensate for" and in this sense there would not be any "adverse effects". But you have to understand that this waveguide would exhibit a falling response at 6 dB/oct throughout its entire operating range. This is not "adverse" to me because I can just have an amp with a + 6 dB/oct characteristic and all is copasetic.
Now in the real world ALL of the above is fraught with a myriad of problems, but you asked "theoretically".
A spool of PLA is $20, and you could easily make a 15" waveguide using a single spool, if not two
The JBL 2384 is an excellent waveguide that should mate up nicely with the 2450SL. I use a 2453H-SL on the 2384 in this package which has some polar measurements. These are biamped using the JBL recommended XO at 630 Hz. I have measured on and off axis and really happy with the performance of these waveguides.
User notnyt at the AVS forum measured several different CD's on the JBL 2384, including a 2452H-SL with the Truextent Be diaphragms. Summary here: Just purchased a pair of JBL 4722n speakers. - Page 136 - AVS Forum | Home Theater Discussions And Reviews
Be measurements here: Just purchased a pair of JBL 4722n speakers. - Page 130 - AVS Forum | Home Theater Discussions And Reviews
JBL 2450SL is a 1,5" exit driver
I think SEOS waveguides are ugly. JBL 2384 even worse. And both dont load well down to 600 Hz. Today i use a Tractrix 200 and it deliver.
Something like this but significant bigger is what i am thinking about: E-OS-15 - Horns by Auto-Tech
I think SEOS waveguides are ugly. JBL 2384 even worse. And both dont load well down to 600 Hz. Today i use a Tractrix 200 and it deliver.
Something like this but significant bigger is what i am thinking about: E-OS-15 - Horns by Auto-Tech
Last edited:
Hi
Eliptical looks good in my system. Square is ugly
The distance beetween the speakers are 2 meter. From the front of the horn to my ears are 2,5 meter.
I am a little conserned about the coherence thoug i dont really feel it is a problem.
The setup on the picture is:https://m.imgur.com/3DAcLJg
Tractrix 200 with JBL2446be
Tractrix 1000 with Radian 475be
Fostex T500
Crossover active: 600/2800/9600 Hz
I have tested JBL M2 with JBL 2450SL and Fostex T500 from 10000Hz. The sound isnt that "big" as with large Tractrix 200 horns. It needs the Fostex T500 on top even if the adverising tells the opposite. The M2 is slightly more coherent, smoother and with a little wider sweet spot, but not that much i was expexting. Therefor i prefer the big horn rigg.
I have also testes 8000 Hz crossover with Tractrix 1000 and TAD2001 on top with a lot of EQ. OK, but it lacks the sweet airy Fostex T500 sound. 8000 Hz crossover make the soundstage a little more coherent but miss some in the 3-4 to 8K area because of beaming i think.
Now i have B&C DM50 from 400 Hz, i like it, funny, not that "brilliant" as beryllium. A little warmer and it handles 400 Hz easy. I have testet this setup directly to Fostex T500 crossed over at 8000 Hz. Maybee one of the best compromisses.
In the B&C setup from 400 Hz i test 18sound XT1086 eliptical CD horn from 1600 Hz with a small 18sound 1" driver with 1,3" voice coil. Works very well. coherent soundstage and very very good treble. Lacks the body of a 2" driver in the +\- 2000 Hz region.
Soon i will test Tractrix 600 with JBL2446be and also TAD2001 with adapter from >1000 Hz to <10000 Hz.
Finally, your question? E-OS with beryllium from 600Hz and all the way up as a point source. Will it sound as huge as Tractrix 200 plus coherent, dynamic and with airy smooth treble?
Eliptical looks good in my system. Square is ugly
The distance beetween the speakers are 2 meter. From the front of the horn to my ears are 2,5 meter.
I am a little conserned about the coherence thoug i dont really feel it is a problem.
The setup on the picture is:https://m.imgur.com/3DAcLJg
Tractrix 200 with JBL2446be
Tractrix 1000 with Radian 475be
Fostex T500
Crossover active: 600/2800/9600 Hz
I have tested JBL M2 with JBL 2450SL and Fostex T500 from 10000Hz. The sound isnt that "big" as with large Tractrix 200 horns. It needs the Fostex T500 on top even if the adverising tells the opposite. The M2 is slightly more coherent, smoother and with a little wider sweet spot, but not that much i was expexting. Therefor i prefer the big horn rigg.
I have also testes 8000 Hz crossover with Tractrix 1000 and TAD2001 on top with a lot of EQ. OK, but it lacks the sweet airy Fostex T500 sound. 8000 Hz crossover make the soundstage a little more coherent but miss some in the 3-4 to 8K area because of beaming i think.
Now i have B&C DM50 from 400 Hz, i like it, funny, not that "brilliant" as beryllium. A little warmer and it handles 400 Hz easy. I have testet this setup directly to Fostex T500 crossed over at 8000 Hz. Maybee one of the best compromisses.
In the B&C setup from 400 Hz i test 18sound XT1086 eliptical CD horn from 1600 Hz with a small 18sound 1" driver with 1,3" voice coil. Works very well. coherent soundstage and very very good treble. Lacks the body of a 2" driver in the +\- 2000 Hz region.
Soon i will test Tractrix 600 with JBL2446be and also TAD2001 with adapter from >1000 Hz to <10000 Hz.
Finally, your question? E-OS with beryllium from 600Hz and all the way up as a point source. Will it sound as huge as Tractrix 200 plus coherent, dynamic and with airy smooth treble?
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.