Edgar

It's been quite a lot longer than that. Yesterday I was reviewing a forum conversation that I had with him back in 2008, when he was known as "Bodcaw Boy."

I've met @Chief bonehead, and he's a regular guy, just like me. On second thought, maybe that's not the best example ...

For innovation, the math can either lead the design, or the design can lead the math. In the former, one can look at all of the equations and notice that setting constraints and variable values in certain ways leads to interesting outcomes, some of which may be useful. In the latter, one has the idea for the interesting outcome first, and then tries to manipulate the math to achieve that outcome. I suspect that Roy's "modified tractrix" followed the latter procedure, and I would find it interesting to see how that happened.

Personally, I'd be very interested in how you turned a tractrix horn into a constant-directivity horn.

Thanks for the correction. Still, three years is a longer time than I realized.

Even if they were (which they aren't), misquoting is bad form. If I had meant "coloration", I'd have said "coloration".

Thanks. But all I see is that @Schu changed my words when he quoted me.

I have no idea what that means. 😕

The 2018 Bonehead class was about maintaining PWK's legacy. Perhaps the next could be a discussion and comparison of horn contours.

Last Bonehead class was in October 2018, I think ... pre-pandemic. Hard to believe that four years have passed.

@Chief bonehead, maybe it's time for another Bonehead class.

No, sorry. Thank you for trying. (It's RR4, 270KΩ -- red|violet|black|orange|brown.)

Didn't anybody warn you about the self-destruct button? 🙂

How is that transmitted? Obviously it's extremely contagious.

As I understand things (I probably read the same thing that you did), Edgar's Speaker Builder article in February, 1981 caught the eye of someone at Klipsch. @Chief bonehead would know for certain.

Paul G.A.H Voigt. Bruce Edgar resurrected the idea in the early 1980s.

Nope! I tried to install all of the resistors so that the color code read in the same direction as the writing under the component. So for horizontal resistors the color code reads left-to-right. For vertical resistors the color code reads bottom-to-top. Doesn't every obsessive circuit builder do the same? 🙂

My latest build. Just finished about fifteen minutes ago. I think I'm posting this just to prove that a theoretical, math-geek DSP electrical engineer can still wield a soldering iron. Can you find the one resistor that is mounted backwards?

My comment was aimed at Cerwin-Vega, not at you.

A speaker that only goes down to 37 Hz (-10dB) is a woofer, not a subwoofer.

Yes, but are they horn-loaded ear buds? 🙂

No, but it will still be moving considerable amounts, in response to those low-frequency signals that it cannot play loud enough for you to hear, adding modulation distortion to what you can hear.

That's another good argument against the idea -- inductors for low cutoff frequencies get very large, very fast. Furthermore, you're trying to design a passive filter for a load whose impedance is varying wildly near the system resonant frequency, so the filter that you design won't be the filter that you actually get. If such a filter is to be used, then it should be placed in the low-level signal chain, i.e., before the amplifier.

Exactly. This was intended for sound reinforcement loudspeakers, as might be used in a theater or performance hall. They face much higher power levels than the typical living room speaker.

That's only true for a closed-box woofer. In a vented box, once below the box tuning frequency the woofer and the port outputs are increasingly out-of-phase. So the woofer excursion increases even when the total radiated acoustical output is decreasing.