• My Response

Congrats on your simple & elegant new design!

I like the bipolar format a lot, though it's seldom used in a high end commercial system. I also really like your driver choice. Very intelligent, going with drivers that have a long x-max. Instead of going all-out for efficiency in your driver selection, you traded off some efficiency for bandwidth. Once again, I think that's the right choice - adequate bandwidth comes first in my book.

The challenge a bipole has competing in the marketplace is mostly one of customer perception. People don't like the idea that half of the money going into drivers is "wasted" on drivers that face the "wrong direction". And on a more objective basis, can the bipole compete with an equal dollar amount of forward facing drivers?

Having built a few experimental bipoles myself, I think the format can be sonically competitive with its dollar equivalent in forward-facing drivers. It's a somewhat different presentation than what you get from forward-facing-only drivers - in some ways better and in some ways worse. But in my opinion it's a very valid way of taking several big steps in the right direction.

Duke

Thanks for the post. Yes, a bipolar does have some applicablity in the world of monopolar boxes and open baffle (dipole) designs. For example, Genesis uses a stereo polar line array woofer stack with a open back dipolar mid/tweeter line array arrangement in a high dollar four box model (they demo'ed this design at the RMAF last fall). A few other commercial speakers use the bipolar concept but they are rare. Too often the bean counters kill multiple driver designs as designers have to compromise what may be a better acoustic solution to satisfy a targeted selling price.

As you suspect, the bipolar solution in my case was an attempt to squeeze as much sensitivity from this driver as I could as it is biased toward low end extension and wide bandwidth. I used the narrow width box and MLTL design to enhance the bass within a small floor space enclosure--more WAF was my goal. The bipolar was intended to handle the baffle step compensation while maintaining the sensitivity as high as I could.

I'll try to hear your new bipolar creation in the near future.

Thanks.

Jim

• AN 8" Speakers

I was amused that Husband wondered if Dicks' box was acting more like a MLTL than a BR. This is one of the few things he actually got right. Of course it's a MLTL. A badly designed MLTL, but a MLTL nevertheless. This helps to explain the hideous FR plot that Husband got. Not to brag, but I get deeper bass out of my FT-1600's with 6" Fostex than Dicks/Husband get with his 8" AN.

OK, OK. I'll stop now.

Bob