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Multi-Way Conventional loudspeakers with crossovers

Is it possible to cover the whole spectrum, high spl, low distortion with a 2-way?
Is it possible to cover the whole spectrum, high spl, low distortion with a 2-way?
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Old 11th September 2019, 04:16 PM   #2891
mabat is offline mabat  Czech Republic
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Quote:
Originally Posted by whgeiger View Post
1) At the point of inflection the radius of curvature of both curves should match.
There is no point of inflection. If you mean at the join, yes, it should match (I guess). It will.

Thanks for the reading. I'm actually quite happy with how it's done now - this is the waveguide I will go for.

Last edited by mabat; 11th September 2019 at 04:26 PM.
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Old 11th September 2019, 04:58 PM   #2892
gedlee is offline gedlee  United States
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Is your mouth simply a linear function of x such that the slope at the junction is the same as the slope of the hyperbola and it is infinite at x = the waveguide length? This function would be easy to compute, and I agree that it would be better than a radius because the rate of change is gradual and happens mostly near the mouth.
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Old 11th September 2019, 05:07 PM   #2893
mabat is offline mabat  Czech Republic
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It's exactly a clothoid (aka Euler spiral), i.e. a curve that has linearly increasing curvature along its length. It is actually quite hard to compute with

Euler spiral - Wikipedia

I believe there are other options of suitable curves - even a whole classes of splines. I chosed clothoid. The first one who suggested it to me was Dr. Bohumil Sżkora, Czech audio guru (I think he has an account here as bobolix). It was the BEM simulation that helped me to realize how much of the horn contour this curve can really take.

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Old 11th September 2019, 05:19 PM   #2894
gedlee is offline gedlee  United States
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I stated that wrong above. No linear function of x could become infinite in a finite x, so it would likely be something like a Tan function, but still pretty simple.

But I agree that this kind of waveguide termination makes a lot more sense than a simple radius - which has an instantaneous change in slope at the junction. I wish that I had thought of this before.
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Old 11th September 2019, 05:23 PM   #2895
mabat is offline mabat  Czech Republic
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I suppose it might be well approximated by something easier to compute. I haven't tried that. I thought about (Bezier) splines but that's not simpler at all in the end.
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Old 11th September 2019, 07:59 PM   #2896
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Status update, was able to get contact with AE through Facebook messenger, couldn’t get the 18h+ in 16ohm and was made aware that I was fortunate to be able to get the TD15M in 16 ohms, as such special request are fulfilled only with special orders which normally require a minimum order count. 8 ohms for the sub is probably trivial to the sum. I’m not sure if I want to run the sub sealed or ported. The fs of that sub is 35hz vs 20hz of the td15h but I feel the larger diaphragm, lower excursion is a good thing. Anyone think that the 15H is better based of the fs? If I chase loudness goals the 15H runs outside it’s xmax, but below xmech, the 18 stays within xmax and I figured the lowered excursion was a bigger deal than the fs...I understand how this results, playing below the port tuning, when tuned to fs, but, if I ran them sealed is the woofer fs so significant in regards to the spectrum played below it? I’m not sure if that’s a win either since sealed increase excursion by large. Looking for some opinions

Last edited by camplo; 11th September 2019 at 08:11 PM.
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Old 11th September 2019, 08:11 PM   #2897
silverprout is offline silverprout  France
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Quote:
Originally Posted by camplo View Post
Status update, was able to get contact with AE through Facebook messenger, couldnít get the 18h+ in 16ohm and was made aware that I was fortunate to be able to get the TD15M in 16 ohms, as such special request are fulfilled only with special orders which normally require a minimum order count. 8 ohms for the sub is probably trivial to the sum. Iím not sure if I want to run the sub sealed or ported. The fs of that sub is 35hz vs 20hz of the td15h but I feel the larger diaphragm, lower excursion is a good thing. Anything that the 15H is better based of the fs? If I chase loudness goals the 15H runs outside itís xmax, I figured the lowered excursion was a bigger deal than the fs...I understood how this results, playing below the port tuning, if I ran them sealed is the woofer fs so significant in regards to the spectrum played below it? Iím not sure if thatís win either since sealed increase excursion by large. Looking for some opinions
Do you really plan to obtain some bass rendering of this thin and flabby cone ?
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Old 11th September 2019, 08:30 PM   #2898
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That’s why I’m here, for the learning. Sounds like youre suggesting that AE isn’t ideal for a subwoofer? When I first suggested the 18h+ for the sub I didn’t receive any negative commentary...until now
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Old 11th September 2019, 11:31 PM   #2899
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As for 'thin/flabby', the video combined with others AE experience indicates it's plenty rigid, but short of an IB to ~mimic the video's air mass load, won't know how stiff it is until being driven hard in the cab. That said, known John, Nick since their beginnings and they've learned not just the physics, but the 'art' of driver design, so wouldn't think twice about recommending or using them.

Again, 'horses for courses'; you ideally want the Fs to be at/below whatever the lowest frequency it's likely to need to reproduce at some useful SPL. With a 29 Hz Fs I don't see how they can legitimately list it as suitable for HT, which always been referenced to 20 Hz nor low enough for a modern studio monitoring app, but if your music doesn't go below the lowest note on a piano [27.5 Hz] it's low enough.

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Old 11th September 2019, 11:50 PM   #2900
ScottG is offline ScottG  United States
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Quote:
Originally Posted by camplo View Post
Thatís why Iím here, for the learning. Sounds like youre suggesting that AE isnít ideal for a subwoofer? When I first suggested the 18h+ for the sub I didnít receive any negative commentary...until now
The 18h has 14mm and a lot more surface area vs.

15m which has only 6mm and a lot less surface area. Plus the resonant freq. is higher.


-the 15m really shouldn't be considered a subwoofer in any high spl design - it just doesn't have the linear excursion.


As far a "flabby" is concerned - that's an issue with diaphragm "buckling" (mostly around the surround/outer-cone edge) which almost all cones have to some degree. In fact the AE driver's also have this, but overall they are more controlled than most within their linear range owing to their curve-linear cone.
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