6db slope ribbon + driver, possible ?

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Jordan jx92s + Aurum Cantus g2si (single cap on it, at 21,500hz).

here is a reviw from april 2010.
UltraAudio.com Equipment Review - Van Zyl Audio Frontline Loudspeakers (4/2010)

I know that Griffin's design is well recommended.
The decrease in distortion along with better dispersion is probably why full range driver fans leave their safety zone.

Over on the straight 8 thread on the bottlehead forum. they mentioned the g2si
Straight 8 - the only Bottlehead speaker kit
"Aurum Cantus ribbon we tried many times to make this work, mostly in the Straight 8 but with the intention of using it with the Climax as another option. The difficulty was a huge resonance around 1700Hz (if I recall correctly) which is quite audible because it is right in the middle of the midrange where the ear is most sensitive. The last crossover design I made for it had a big notch to correct teh resonance, but it did not work as intended and did not alleviate the sonic problem. In addition, the ribbon was very easily damaged by testing (we blew out a number of them) and a half hour of Nine Inch Nails through a Paramount was enough to make the ribbon sag visibly. So I gave up on it, there is no crossover I can recommend. A very airy tweeter, I would not hesitate to use them as a supertweeter crossed at 8kHz or higher, second order or steeper."

I think that a clone of the van Zyl Audio is possible ( using alpairs) assuming micro volume levels, what'cha think ?

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2007-01-24 2:28 pm
Hi Norman,

I got to hear those speakers at LSAF in Dallas this year. They had incredible punchy clean, clear bass. I was expecting much less bass but it was abundant. I got to chat with the designer and he was super enthusiastic and happy to talk technical stuff. But the room was crowded.

What I wanted to ask him is: how is this a tapped tractrix horn, since it doesn't open up to 180 degrees? (Well, it sort of does since the sound hits the floor, but it still looks like it must be truncated or something like that.)

So I wonder what's the advantage of a "compromised tractrix" (if that's what it is) over other expansions? Is it just to get a short length?

In terms of cloning, do you mean make a BLH with these drivers, with the 6db/octave high pass to the tweeter? Or do you mean make a BLH with Jim Griffin's crossover adapted to the Alpairs?
Good to hear you liked them.

If I'm right, doesn't a tranmission line decrease cone motion, unlike a ported that stops cone motion at tuning and a little a half an octave up ?

So, the box is much of the magic.

I think alpair 10's with a single capped tweeter (or a resistor if attenuation needed) can work.


Bob Brines

2003-01-31 10:11 pm
If I'm right, doesn't a tranmission line decrease cone motion, unlike a ported that stops cone motion at tuning and a little a half an octave up ?

Well, not really. If by "transmission line" you mean a resonant quarter-wave pipe, the damping action of the unstuffed pipe is exactly like a BR. A MLTL does seem to unload more gracefully than a BR, but I don't know why nor can I prove it. If by "transmission line" you mean an end loaded pipe stuffed until only a single impedance peak is left, then the pipe won't damp the driver at all. A classic TL behaves as if it were an infinite baffle with regard to cone excursion.