I have never heard a CD Horn in a home setting, and wondered if anyone has compared them to say an Altec 511 or 811 ?

I was looking at some Altec Manta Ray and big JBL CD horns.

Any thoughts ?

Not sure if this tells you anything about CD drivers in general, but at least it shows that they can work well.

Dave

In my experience, CD horns and waveguides can be hard to cross over. Wayne's paper on crossover networks is an excellent source of information. My attempts at crossing over horn-based systems were disastrous before I got hold of his paper.

I have a friend who went from the big Altec sectoral horns (both the 511 and 811) to CD waveguides and he is happy with the results. Two of the speaker lines I sell use CD waveguides.

What Wayne is doing in his designs - using CD horns and matching up the woofer and horn pattern (at least in the horizontal) in the crossover region is in my opinion very intelligent. I think Altec was the first to do this with the Model 19 and Model 14 years ago, but even today few designs really pay attention to the radiation pattern.

Shortly after the Altec Model 19 and Model 14 came out, JBL took it one step further with the Model 4430 studio monitor. Below is a link to a paper JBL's top engineers wrote describing the theory behind the model 4430 (link hosted by Wayne at PiSpeakers - surprise, surprise!).

Duke

• landmark JBL paper on CD loudspeaker system

Where do i find Wayne's crossover paper ?

Glad you liked it!

Wayne's crossover paper is linked to on the "info" page at his website. I think the link below will take you to that page. Under "Helpful documents and software" down at the bottom, it's the third item.

I am amazed at the time and knowledge Wayne shares for free. I try to send people in his direction - not with every post I make, but whenever I think Wayne has something to offer that would serve them well. I still haven't figured out how he makes money at this. If you find his crossover document helpful, let people who might be interested in his designs know about him and his website.

Duke

• http://www.pispeakers.com/contents.html

Constraining the radiation angle is what the horn flare is for. The wall angle of a horn sets its pattern and constant directivity horns have straight walls. Some widen near the mouth because the pattern tends to narrow slightly near the lower cutoff but the wall angle of a CD horn is straight (or nearly straight) along most of the flare.

Norris Wilson