Jeff,
During your trials of speaker design have you concluded that you prefer an open baffle type speaker?
Have you experimented with a rear-firing tweeter? Have you explored a free-air woofer approach? From some reading I have done on the web, it seems the polar response improves with both approaches.
What led you to choose the PHL driver? Can you go over the benefits you found from a more sensitive midrange opposed to a midrange with more xmax like like the Orion and NaO (multiple versions) offer?
edited: I found good information about the design from the htguide.com forum.
Sorry for the delay in replying. My interet service is changing and it left me without access for the last few days.
If you read the thread at the HTguide forum then you have learned quite a bit already. However, your questions are a little tough to answer.
"Do I prefer an open baffle type speaker?" Well, I really liked this new speaker and I would love to have it in my home again for a while longer, maybe even forever
I think the design really worked and Jim hit a home run with the cabinet. After I finally saw them and heard them, I was really wishing I owned them.
I'm just happy to have designed them now.
But, these aren't the only speakers I like. I still really like my Focal 4-ways that I have in my family room, and I even have a little mini-monitor that I love to listen to at times too. The things is, what I like is a speaker that sounds natural to me. The open baffle midrange can certainly do this, and the PHL has excellent resolution and is certainly open and spacious sounding. This is very seductive, and creates a deep soundstage that can be very convincing. Since it is only a dipole down to around 400Hz or so I don't have to deal with the dipole effects on the bass response, which I think is a real plus here, and makes this a very easy design to live with in real rooms.
At this time I am not really interested in pursuing a full-range dipole with an open baffle woofer. To work right this requires active equalization and places some strong demands on the woofer and amplifier in the low bass. I also still feel that monopole bass works very well, especially with regards to room pressurization in the deep bass. So, at this time, and until I have some epiphany, that is my preference.
Yes, I have tried a rear mounted tweeter. I did not like the sound. It was difficult to get a natural sounding tonal balance, and in the end I had to lower its output quite a bit to get there. I have built bipolar designs before too, and intentionally used only woofers or mids on the back with no tweeter because I did not like the sound I got bouncing those highs around the room. Linkwitz and I have discussed this and we share the same views on this matter.
I hope this helps answer your questions. I'm sorry if the answers aren't specific enough. Preferences are a funny thing.
Jeff B.
