In a way that null will be narrowed if and when I build the narrow cage and put super strong neodymium magnets in a lattice of sorts that is pretty much less than an inch wide. I am also leaving myself the option of moving the metal parts in this horn to get a better spread. Now remember the comb structure in the present heil is a lot of
obstruction to sound as well. My lattice should have a lot less of it. Its all in my head at this point, I have 2 working heils and I may be playing with the third.
Cool.
Srinath.
obstruction to sound as well. My lattice should have a lot less of it. Its all in my head at this point, I have 2 working heils and I may be playing with the third.
Cool.
Srinath.
You're still sending the radiation up against a near parallel surface, which will completely destroy the highs with standing waves and reflections back to the diaphragm, and a smaller magnet structure will increase, not decrease, the dipole null, though the horn complicates matters. Frankly it's a bad idea. You'll have a huge amount of standing waves in the throat and what makes it out will be a goofy combination of cancellations and peaks.
If you're interested in a modernized AMT check out the Beyma TP150, it's much more svelte than the AMT1. I do wish someone else would pipe in here, I know it seems like I'm trying to rain on your parade but that's not my intent, it really is a problematic idea.
Best,
b
Oh no rain, I am good with any and all ideas, cos I am trying avoid making 10 things that dont work. How about a straight 45 degree surface instead of a curved ...
I am probably going to split up a horn and look inside of it. The horns have a block of some kind that forces sound to do something ...
I'll look @ the beymaTP150 for sure.
Cool.
Srinath.
I am probably going to split up a horn and look inside of it. The horns have a block of some kind that forces sound to do something ...
I'll look @ the beymaTP150 for sure.
Cool.
Srinath.
The shape of the horn is the minor issue with throat reflections. The cancellation is the major issue, you'd get not only an incredibly jagged (and unstable) F.R., it'd be nominally LESS sensitive than the forward wave of an unmolested heil. If it were a bipolar source rather than a dipole, the better method would be per this pic, with the ribbon as the source and the expansion utilizing the one magnet wall, and a round section added to the side of the heil, basically forming a teardrop phaseplug. But because it's a dipole, they don't sum but rather cancel, and you'd get an even lower output from this arrangement than yours, because the summation would be much more coherent and there wouldn't be the randomizing factors of stored energy in the throat.
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Only works with a bipole source, not the dipole that the AMT is. Dispersion would be defined by what you did with the round part of the teardrop shape, and the angles of the sidewalls. I'd expect it to be fairly good at constant directivity in the horizontal band, but none of it matters. It's a dipole and won't work accordingly.
No, by hornloading it, it is expected narrow the beamwidth to about a nominal 90 degree horizontal pattern, above 1k or so. One would expect that below that it would expand but would only be a slight bulge in dispersion before the dipole cancellation defines a more narrow coverage pattern. Vertical is more complex since it's a 4" tall source rather than 1" wide.
I'm hoping for smoother response, and in particular a boost of the little shelf we see in the response curve from 1-2k. The smoother response is expected due to the improved termination. There's a short horn inherent in the magnet structure, but it's terminated with a relatively harsh 45 degree edge. Part of what does good off-axis smoothness in a good design is proper edge termination, which the AMT1 lack. I'm hoping to get clean relatively CD response.
Badman,
I would really like to see how much the AMT1 improves when you stack them in your waveguide frame. I invite you to invert one on top of the other and take a quick measurement. I would expect the differences in diaphragms adding together would go a long ways to smoothing out the frequency response.
Just my 2 cents worth ...
I would really like to see how much the AMT1 improves when you stack them in your waveguide frame. I invite you to invert one on top of the other and take a quick measurement. I would expect the differences in diaphragms adding together would go a long ways to smoothing out the frequency response.
Just my 2 cents worth ...
Let me see if I can rig that up when I get measurements done. I'm still in the assembly phase. I need to create and mount the triangular insets, as well as apply the kerf-cut rounded outer pieces (which are all cut), and smooth the top profile for mounting of the vertical horn component.
Best,
b
Best,
b
It's wood. The renderings show the material- the large rounded parts are MDF and the rest is ply. The material is largely irrelevant since it's not going to be open and porous- the MDF will be sealed. Any proper solid will perform very similarly (though not identically) so long as it's stable and sealed. The difference between "directing" and "reflecting" in purely semantic, you're probably considering the angle of incidence as the primary factor.
I've read through this tread from time to time. I love the AMT. Here is a pic of how use them. Those are Edgarhorns with JBL 2441 Compression drivers, and the bass bins are JBL Scoops with JBL 2205 15" woofers. I also have a DIY Martin Logan sub in each corner. Cheers.
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At the time I was tri amping through a Behringer 3400. Crossed at 700hz and 7000hz. Yep the 2225 is just an updated version of the 2205 but still alnico. The support is oak with Cherry Bloosum stain. I've changed over to horn a friend and I design and had CNCed out of pine just for the test bed. We had a pair CNCed out of Mahagony and had a local woodworker build bass bins for Lamda TD15s. In the pix we were not running the Heils but are now. Here are pics of the first pair.
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I cannot find this. I see speakers that look like regulay drivers, and tall speakers with woofers on the side. Nothing else.
I've seen the aulos and the syrinx though. 45 degree woofer and heil in front of it. That will work great. I know that. That thing just looks even worse than the amt1b though.
Cool.
Srinath.
Beyma TPL-150 pleated diaphragm tweeter - Beyma TPL-150 - Beyma TPL-150 high frequency tweeter. Beyma TPL-150 high frequency tweeter is available here at US Speaker. Beyma TPL-150 speaker components.
I clamped up some of them last night, but the kerfed piece broke partway through the glue-up on one.... which is a real stinker, re-fabbing that piece is going to be an excercise in patience (cut, move fence 1/4", cut, move fence 1/4"). I'll have to move the fence 50% more times too, as I have to kerf the replacement panel differently than I did the originals since a section of the piece is permanently attached and I don't wish to refabricate the roundover section.
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