What this does is exactly what PB mentioned, you push the crossover higher by using a smaller (vertical) waveguide.
Martin, was going to say the same thing in reverse, that narrowing the vertical dispersion would result in a vertical profile of greater length and/or height.
Guys, that's what I was talking about in the first place! I guess it wasn't a very clear post. Let me try again:
I'm not sure if you're referring to a particular "econowave" speaker, but a good one should be able to do a bit better than 10', and those asymmetrical CD waveguides are already the compromise you (PB) suggest in your next post, are they not? If you try to go even smaller than that, it gets very difficult to stay 2-way.
better? 😉
I'm not sure if you're referring to a particular "econowave" speaker, but a good one should be able to do a bit better than 10', and those asymmetrical CD waveguides are already the compromise you (PB) suggest in your next post, are they not? If you try to go even smaller than that, it gets very difficult to stay 2-way.
better? 😉
110dB? Baby food ... . Try a Community PC1542M midrange horn: sensitivity 117dB, 200Hz-2kHz; 147dB peak - full assembly weighs 45Kg
The high sensitivity comes from the restricted directivity of the horn. The M4 driver does not do 117db 1W/1M.
Yes, the M4's output is dependent on the attached horn - some time ago I was interested in what driver had the highest true output, and this chap stood out. It was rated some years ago as the most efficient driver available, I wonder if that is still the case ... ?
The M4 is very efficient and handles lots of power. It does a bit better than specified as the meter Community used to use to set 1 watt of noise read high by about 2 dB.
I sent them a NIST traceable Fluke 87, so the newer stuff is accurate.
If anyone wants to play with an M4 I have four of them up on eBay.
I sent them a NIST traceable Fluke 87, so the newer stuff is accurate.
If anyone wants to play with an M4 I have four of them up on eBay.
The M4 is not a suitable driver for home Hi-Fi. I've tried all three revisions of it. In every case it lacked nuance and refinement. The composite coned ones were the least offensive, with the aluminum/foam sandwich coned ones being completely unlistenable.
Here's what I don't understand about conical horns? What's wrong with them? They are by nature Constant Directivity, or Constant-Q. Meyer, EV, harman, all have stacks of patents on CD horns and none of them are as simple as a straight sided square, cone or flattened pyramid.
In other words, if they were so good and clearly so simple, why haven't they had use before. Meyer CD designs are even supposed to help with the nonlinearity of air. Many designs narrow near the throat or do lots of other funky things.
In other words, if they were so good and clearly so simple, why haven't they had use before. Meyer CD designs are even supposed to help with the nonlinearity of air. Many designs narrow near the throat or do lots of other funky things.
That's good, & means that the room the're in can't significantly negatively affect the performance.
Obviously that's dependent on the site owners organising/allowing etc people to do that.
Take a look @ some drivers from BMS/Radian/Beyma/ For eg, BMS 4595ND = 118dB SPL @ 1W/1m on a 2242 Horn BMS 4595ND Neodymium Coaxial High frequency Compression Driver - BMS 4595ND - BMS 4595ND lightweight neodymium 1.5" coaxial high frequency compression driver. BMS neodymium 4595ND dual voice 1.5" coaxial high frequency compression drivers are availab
Overview
Even without the 2242 Horn, it's more than 110dB
I agree it is difficult to understand the relationships and the pros and cons of the various horn and waveguide designs.
For example, the L'Cleach designs show how a big turned back mouth lip smooths response, yet with the typical conical horn there is an abrupt transition out to the world at the end of the mouth with no rounding.
Shooting from the hip now, I seem to recall that Webster's equations for the exponential expansion gave even loading (I so do not want to use the word "constant") to the diaphragm, the others do not. This was seen as an important design goal, so most horn designs for decades followed this idea.
_-_-bear
The "typical" Synergy conical horns don't round the mouth transitions as much as many "pretty" designs, but the horn break is not an acoustically abrupt transition. The expanding transition reduces HF diffraction while making the horn "semi-exponential" at the lower frequencies.
If using a single HF driver down much below 1000 Hz is a goal, exponential or similar loading may be needed,(or desirable) but the Synergy concept is to use appropriate drivers and taps in the horn to eliminate the HF driver's excursion limits as a design limitation.
This allows a single source point horn that can cover a much wider bandwidth with constant directivity and no source astigmatism as experienced with "pinched throat" constant directivity designs.
Attachments
If you want a horn that loads the bass end well for it's size, or if you want a horn that reduces the mouth transition with it's flare, conical seems to have the least in both cases.
A conical horn (especially a more narrow one) with a large roundover does resemble a number of other profiles to some degree or another. The hyperbolic profile resembles a conical horn that has had a mouth roundover (adjustable) integrated in to it.
Art,
I have never heard the Synergy, and have only had cursory contact with the Unity horns... but unless there is something very different between the breakovers in the Synergy vs the MantaRay I'd expect a problem. There may well be some very important differences. I don't know.
As far as "pretty" designs, pretty has nothing to do with the measurements. I expect you followed JMMC's thread, so you've see what I and everyone else has?
Also I think Geddes has commented on the effects of a change in flare rate between the drivers throat where it exits to the expansion of the horn causing issues. I'm unclear how or if the Synergy or any conical expansion deal with this potential problem.
I have never heard the Synergy, and have only had cursory contact with the Unity horns... but unless there is something very different between the breakovers in the Synergy vs the MantaRay I'd expect a problem. There may well be some very important differences. I don't know.
As far as "pretty" designs, pretty has nothing to do with the measurements. I expect you followed JMMC's thread, so you've see what I and everyone else has?
Also I think Geddes has commented on the effects of a change in flare rate between the drivers throat where it exits to the expansion of the horn causing issues. I'm unclear how or if the Synergy or any conical expansion deal with this potential problem.
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