salas said:
LF effect for horns or waveguides is pretty much irrelavent IMO. I'm not talking about LF effects, I'm talking about directivity control. Diffraction takes less space to get a wide pattern than a waveguide. Its easy to diffract a wave to be wide, but its very difficult to coax it into a spherical shape without diffraction. Its takes length and mouth area to get good control with low diffraction. All this has nothing to do with LF response - waveguides and horns all work about the same at the LF end (contrary to the posted simulations).
"The impulse looks funny. Normally the leading edge of the impulse should be going upward. If it goes downward, it's either the mic signal is inverted (as most Panasonic WM61 type mics), or driver related issues (haven't figured this out yet)."
The drivers may have been phased differently depending on the amp used or if I simply goofed up with the polarity when I hooked up the drivers. It's the same driver in the 2307,2344,2370
Rob
The drivers may have been phased differently depending on the amp used or if I simply goofed up with the polarity when I hooked up the drivers. It's the same driver in the 2307,2344,2370
Rob
gedlee said:
Tinitus means compression driver, not constant directivity.
With minimal horns, they are sold as "Arrayable waveguide elements."
http://bmspro.com/4510ND.bms_4510nd0.0.html
Unterminated, they're diffraction devices.
With no horn, the phase plug is the waveguide, uhmm, "horn."
With no phase plug, they're inverted domes on a short transmission line.
Yeah, all that's been measured, of course. We can do it ourselves, if desired....
Variac said:
Notice the complete lack of mention of my work. I consulted for Peavy on waveguides a few years before they filed that patent. Very tacky IMO.
They simplified the waveguide by using a circular arc from the throat to the conical sides and called it "revolutionary". Its just a simplified OS contour and I posted the two shapes on my web site once showing how they were very similar. However, the OS will still have less diffraction so why not just do it right? Oh, yea, can't patent that!! But the patent that they got was pointless anyways since they blew it in the claims. Anyone can beat their patent by just doing it better - use an OS contour!
Yes, it is a waveguide since it does not use diffraction per-see, but it is not a "good" waveguide because it is sub-optimal.
Variac said:
This is not stricktly true, it is illegal to "build, have built or otherwise assemble" no matter who you are. Its just very difficult to catch you. However, and I know this first hand, if you post how to easily infringe a patent, like you just did, then you could be guilty of "inducing to infringe" which is also a crime. Bose tried to get me on that law.
Robh3606 said:
Yep! I know those. =) Did Altec ever do that, or was it just the Urei?
Variac said:
It would work, but maybe not in the same way. The idea is to get a smooth impedance transition at the edge. A sharp terminations causes artifacts. Probably form resonance at the mouth, but I'm not sure.
What I am sure of is that I can both hear and measure it.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=103787&highlight=
Foam, roll-overs, towels, edge slots. There are many different ways to do it.
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