What I’m trying to say is simpler than that. A longer waveguide will perform worse at lower frequency directivity control. It will need to have an even larger mouth again to keep up.
The increase in horn efficiency is of no real interest to waveguiding. If anything, it doesn’t help due to the increased group delay.
Here is a thread supporting the idea that narrow is not a panacea.
https://www.diyaudio.com/community/threads/is-it-best-to-use-a-non-axisymmetric-waveguide.375799/
The increase in horn efficiency is of no real interest to waveguiding. If anything, it doesn’t help due to the increased group delay.
Here is a thread supporting the idea that narrow is not a panacea.
https://www.diyaudio.com/community/threads/is-it-best-to-use-a-non-axisymmetric-waveguide.375799/
Communication seems to be failing between us, with you getting the exact opposite meaning of what I wanted to say, twice now.
I suggest a shallow waveguide could have less diffraction effects than a deep one. (I'm referring to diffraction internal to the waveguide, not cabinet edge diffraction). I said nothing about a deeper waveguide helping with diffraction.
I'm not really asking about how waveguides affect the sound, I just wondered if compression drivers work okay with shallow waveguides as I usually see them in much deeper ones than used with direct radiator drivers. Seems like they can do.
Neither shallow nor deep will produce a problem if you design them properly. If you want easy then make the easiest of all, a flat baffle.
Does that help to show why I’m going in that direction?
To answer your question more directly, you can use a compression driver with no waveguide. There was a recent thread on that topic.. or anything in between.
Does that help to show why I’m going in that direction?
To answer your question more directly, you can use a compression driver with no waveguide. There was a recent thread on that topic.. or anything in between.
Based on what I have observed, the deeper devices have typicaly very little internal diffraction, but the bigger problem is the mouth. With the shallower it's the opposite - less problems with the mouth but worse regarding the throat. A lot depends on the source shape - more or less flat wavefronts produced by compression drivers just tend to work better with narrower coverages, whereas the shapes of dome tweeters generally work pretty well with shallow, wide-directivity waveguides (interestingly, the taller the dome, the better). Flat baffle, being an example of a very shallow one, is not a good match at all to a dome tweeter, BTW, neither to a compression driver.
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I am just pondering a reasonably compact speaker using a coaxial mid/high compression driver with wide dispersion shallow waveguide. Perhaps it would approximate a KEF reference 1 but with a slightly higher xover point.
I'm sure 90 degree horns in the room corner suit some people, but it's not for me either visually nor sonically.
With a 1.4" flat wavefront you can have wide dispersion but not to very high frequency.
Even the M2 waveguide does not maintain the low DI up in the high treble. To what degree this is desirable or not, is likely unknown.
As mabat points out. Even the shallow waveguides on the Revel tweeters 1" don't maintain DI all the way up. Probably by design more important to match DI through crossover. As long as you will be in the "cone" of that response at the listening position does it matter?
Me no I don't need constant DI above 8-10K or so but that's my take yours may be different.
Rob 🙂
I guess it could if the goal was such. It's in general possible to do with a dome tweeter. It's possible that the sensitivity would drop too low in the top octave (which is very real once you start making the DI more flat), which is of course a problem for a passive-crossover design.
Diffraction = acoustic impedance mismatch.
So anything like a irregular shape where (sound) waves leave from.
Well, it's a lot more complex than that. But let's stick to a simple summary.
So the shallowness has nothing to do with diffraction problems on itself.
The shape of it does.
If that is a horn or a waveguide is totally not relevant.
In fact, as far as I know waveguides and horns can be the same thing.
A waveguide is just optimized for better directivity response.
Like I mentioned earlier, that's the main only reason Geddes was starting to use that term.
The waveguide he's using are basically just horns from a size and depth point of view.
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Yes it can matter, as it is also the power response that's important when listening in a (reverberant) room.
The way versions of the HF content arrives to the a listener in terms of FR and time has an impact on the experience for sure. The "cone" is not isolated.
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Absolutely agree was thinking of CD horns/waveguides where even then the DI goes up like the M2. Depends on how much and what frequency range. Above 8-10K you think it matters?
Rob 🙂
LOL OK
Is there anything out there that doesn't show a rise in DI in the last octave? Is there a system that exists that has a flat DI 1K to 20K?
Rob 🙂